JP4135027B2 - Power converter and control method of power converter - Google Patents

Description

  The present invention relates to a power converter and a method for controlling the power converter.

  As a typical circuit configuration of an inverter, an indirect AC power conversion circuit that converts commercial AC to DC via a rectifier circuit and a smoothing circuit and outputs desired AC by a voltage source converter is generally used. On the other hand, as a method of obtaining AC output directly from AC voltage, a direct power converter represented by a matrix converter is known, and a large capacitor or reactor for smoothing voltage pulsation due to commercial frequency is not required. The conversion device can be expected to be miniaturized, and has recently been attracting attention as a next-generation power conversion device.

  The conventional direct power converter includes a PWM rectifier that converts a three-phase AC voltage into a DC voltage, and a PWM inverter that converts the DC voltage converted by the PWM rectifier into a predetermined three-phase AC output voltage. There is a thing (for example, refer to JP, 2004-266972, A (patent documents 1)).

  This direct power converter generates a trapezoidal wave command signal based on an input current command, compares the trapezoidal wave command signal with a carrier signal, and generates a PWM modulation signal that turns on and off the switching circuit of the PWM rectifier. Yes. Also, a PWM modulation signal for turning on / off the switching circuit of the PWM inverter is generated by comparing a triangular wave obtained by modifying the carrier signal with an output voltage command.

  However, since the direct power converter generates the trapezoidal wave command signal by calculation based on the input current command, there is a problem that the calculation load of the control unit increases.

In the direct power converter, the carrier waveform on the PWM inverter side needs to be deformed, so that the modulation waveform generation is complicated and the control circuit is complicated. Further, when a carrier generation circuit for supplying a carrier signal is separately used for the PWM rectifier and the PWM inverter, there is a problem that the circuit of the control unit becomes complicated.
JP 2004-266972 A

  Accordingly, an object of the present invention is to provide a power conversion device and a method for controlling the power conversion device that can reduce the calculation load of the control unit with a simple configuration.

  Another object of the present invention is to provide a power conversion device and a method for controlling the power conversion device that can simplify the circuit of the control unit.

(ただし、ｄ_s ^*,ｄ_t ^*は線電流通流比、位相角φは０≦φ≦π／３)
で表される所定の式を用いて生成するか、または、上記所定の式に基づいて予め設定されたテーブルを用いて生成し、線電流通流比ｄ_s ^*の絶対値と線電流通流比ｄ_t ^*の絶対値が、上記三相交流入力電圧の３つの相のうちの２つの相に対応する上記台形波状の指令信号の傾斜領域を夫々表すと共に、線電流通流比ｄ_s ^*,ｄ_t ^*から決まる線電流通流比ｄ_r ^*の絶対値が、残りの相に対応する上記台形波状の指令信号の傾斜領域を表すと共に、
上記線電流通流比ｄ _s ^* の絶対値が１のときは、|ｄ _r ^* |＝１−|ｄ _t ^* |であり、上記線電流通流比ｄ _t ^* の絶対値が１のときは、|ｄ _r ^* |＝１−|ｄ _s ^* |であり、上記線電流通流比ｄ _s ^* の絶対値とｄ _t ^* の絶対値のいずれもが１でないときは、|ｄ _r ^* |＝１であることを特徴とする。
ここで、上記指令信号生成部により台形波状の指令信号を生成するときの上記基準信号は、変換部が三相交流入力電圧を直流電圧に変換する場合は、三相交流入力電圧のうちの基準となる信号を用い、変換部が直流電圧を三相交流出力電圧に変換する場合は、例えば上記三相交流出力電圧を作るための基準となる信号を用いる。 To solve the above problems, the power conversion device of this invention,
A converter unit that converts a three-phase AC input voltage into a DC voltage; and an inverter unit that converts the DC voltage converted by the converter unit into a predetermined three-phase AC output voltage. The converter unit and the inverter unit A power converter that does not have a smoothing filter in the DC link part connecting
A command signal generator for a converter unit that generates a trapezoidal wave command signal for a converter unit based on a phase angle of a reference signal generated so as to be synchronized with the three-phase AC input voltage;
A carrier signal generator for generating a carrier signal;
An inverter command signal generator for generating an inverter command signal for outputting the predetermined three-phase AC output voltage;
The trapezoidal converter unit command signal from the converter unit command signal generation unit is a three-phase command signal represented by a phase voltage, and one phase command signal of the three-phase command signals is A two-phase command detection unit for detecting a conduction ratio of other two-phase command signals that are switched when representing a conduction state;
The inverter unit command is based on the current ratio from the two-phase command detection unit so that the inverter unit can perform pulse width modulation using the same carrier signal as that used in the converter unit. The amplitude of the inverter unit command signal from the signal generation unit is corrected, and one command signal represented by the current ratio is offset in two switching states of the corrected inverter unit command signal. An arithmetic unit that inverts the polarity of the other command signal represented by the current ratio ,
The converter unit is configured to perform the three-phase operation by a pulse width modulation method based on a comparison result between the trapezoidal converter unit command signal from the converter unit command signal generation unit and the carrier signal from the carrier signal generation unit. Convert AC input voltage to the above DC voltage,
The inverter unit converts the direct current converted by the converter unit by a pulse width modulation method based on a comparison result between the inverter command signal corrected by the arithmetic unit and the carrier signal from the carrier signal generation unit. The voltage is converted into the predetermined three-phase AC output voltage,
The converter unit command signal generation unit is configured to determine the slope region of the trapezoidal converter unit command signal.

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Or by using a table set in advance based on the predetermined formula, and the absolute value of the line current conduction ratio d _s ^* and the line current conduction The absolute value of the ratio d _t ^* represents the slope region of the trapezoidal command signal corresponding to two of the three phases of the three-phase AC input voltage, and the line current conduction ratio d _s ^*. , d _t ^*, the absolute value of the line current conduction ratio _dr ^* represents the slope region of the trapezoidal wave-shaped command signal corresponding to the remaining phase ,
When the absolute value of the line current conduction ratio d _s ^* is 1, | d _r ^* | = 1− | d _t ^* |, and when the absolute value of the line current conduction ratio d _t ^* is 1. Is | d _r ^* | = 1− | d _s ^* |, and when neither the absolute value of the line current conduction ratio d _s ^* nor the absolute value of d _t ^* is equal to 1, | d _r ^* | = 1 .
Here, the reference signal when generating the trapezoidal wave-shaped command signal by the command signal generation unit is the reference of the three-phase AC input voltage when the conversion unit converts the three-phase AC input voltage into the DC voltage. When the converter converts the DC voltage into a three-phase AC output voltage, for example, a signal serving as a reference for generating the three-phase AC output voltage is used.

(ただし、ｄ_s ^*,ｄ_t ^*は線電流通流比、位相角φは０≦φ≦π／３)
に基づいて生成することによって、複雑な演算により台形波状のコンバータ部用指令信号を形成する必要がなく、簡単な構成で制御部の演算負荷を低減できる。 According to the power conversion device having the above configuration, for the pulsating voltage (current) waveform of the DC voltage converted by the converter unit, the three-phase AC output voltage (current) is not distorted. By correcting the inverter unit command signal by the command signal correcting unit, the DC voltage converted by the converter unit is converted into a predetermined three-phase AC output voltage based on the corrected inverter unit command signal. Is possible. At this time, the command signal generation unit for the converter unit, the slope region of the trapezoidal converter command signal for the trapezoidal wave,

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Therefore, it is not necessary to form a trapezoidal wave command signal for the converter unit by complicated calculation, and the calculation load of the control unit can be reduced with a simple configuration.

Moreover, in the power converter of one embodiment,
The PWM modulation signal generation unit for converter unit that generates the PWM modulation signal for converter unit by comparing the command signal for converter unit from the command signal generation unit for converter unit and the carrier signal from the carrier signal generation unit When,
The inverter part PWM that generates the inverter part PWM modulation signal by comparing the inverter part command signal from the inverter part command signal generation part with the same carrier signal used in the converter part A modulation signal generator,
The converter unit converts the three-phase AC input voltage into the DC voltage based on the converter unit PWM modulation signal generated by the converter unit PWM modulation signal generation unit,
The inverter unit converts the DC voltage converted by the converter unit into the predetermined three-phase AC output voltage based on the PWM modulation signal for the inverter unit generated by the PWM modulation signal generation unit for the inverter unit. And
The converter part
Three switching circuits in which each phase voltage of the three-phase AC input voltage is input to one end and the other end is connected to the first DC link unit,
Each phase voltage of the three-phase AC input voltage is respectively input to one end, and has three switching circuits each connected to the second DC link portion and the other end.
The inverter part is
Three switching circuits in which each output terminal of the predetermined three-phase AC output voltage is connected to one end, and the other end is connected to the first DC link unit;
Each output terminal of the predetermined three-phase AC output voltage is connected to one end, and three switching circuits are connected to the second DC link portion.

Moreover, in the power converter of one embodiment,
The PWM modulation signal generation unit for converter unit that generates the PWM modulation signal for converter unit by comparing the command signal for converter unit from the command signal generation unit for converter unit and the carrier signal from the carrier signal generation unit When,
The inverter part PWM that generates the inverter part PWM modulation signal by comparing the inverter part command signal from the inverter part command signal generation part with the same carrier signal used in the converter part A modulation signal generator,
A matrix converter having a virtual converter unit corresponding to the converter unit, a virtual inverter unit corresponding to the inverter unit, and a virtual DC link unit corresponding to the DC link unit,
The virtual converter unit and the virtual inverter unit are
Three switching circuits in which the first phase voltage of the three-phase AC input voltage is respectively input to one end, and the other end is connected to each output terminal of the predetermined three-phase AC output voltage;
Three switching circuits in which the second phase voltage of the three-phase AC input voltage is respectively input to one end, and the other end is connected to each output terminal of the predetermined three-phase AC output voltage;
A third phase voltage of the three-phase AC input voltage is input to one end, and three switching circuits are connected to the respective output terminals of the predetermined three-phase AC output voltage.
The three-phase AC input voltage based on the converter PWM modulation signal generated by the converter PWM modulation signal generator and the inverter PWM modulation signal generated by the inverter PWM modulation signal generator. Is converted into the predetermined three-phase AC output voltage.

(ただし、ｄ_s ^*,ｄ_t ^*は線電流通流比、位相角φは０≦φ≦π／３)
で表される所定の式を用いて生成するか、または、上記所定の式に基づいて予め設定されたテーブルを用いて生成し、線電流通流比ｄ_s ^*の絶対値と線電流通流比ｄ_t ^*の絶対値が、上記三相交流入力電圧の３つの相のうちの２つの相に対応する上記台形波状の指令信号の傾斜領域を夫々表すと共に、線電流通流比ｄ_s ^*,ｄ_t ^*から決まる線電流通流比ｄ_r ^*の絶対値が、残りの相に対応する上記台形波状の指令信号の傾斜領域を表すと共に、
上記線電流通流比ｄ _s ^* の絶対値が１のときは、|ｄ _r ^* |＝１−|ｄ _t ^* |であり、上記線電流通流比ｄ _t ^* の絶対値が１のときは、|ｄ _r ^* |＝１−|ｄ _s ^* |であり、上記線電流通流比ｄ _s ^* の絶対値とｄ _t ^* の絶対値のいずれもが１でないときは、|ｄ _r ^* |＝１であることを特徴とする。 Further, the control method of the power conversion device of this invention,
A converter unit that converts a three-phase AC input voltage into a DC voltage; and an inverter unit that converts the DC voltage converted by the converter unit into a predetermined three-phase AC output voltage. The converter unit and the inverter unit A method of controlling a power converter that does not have a smoothing filter in a DC link unit connecting
Generating a trapezoidal converter unit command signal by the converter unit command signal generation unit based on the phase angle of the reference signal generated so as to be synchronized with the three-phase AC input voltage;
Generating a carrier signal by a carrier signal generator;
Generating an inverter unit command signal for outputting the predetermined three-phase AC output voltage by the inverter unit command signal generation unit;
The trapezoidal converter unit command signal from the converter unit command signal generation unit is a three-phase command signal represented by a phase voltage, and one phase command signal of the three-phase command signals is Detecting a current ratio of other two-phase command signals to be switched when representing a conduction state by a two-phase command detection unit;
Based on the current ratio from the intermediate phase detection unit, the calculation unit allows the inverter to perform the pulse width modulation using the same carrier signal as that used in the converter unit in the inverter unit. The amplitude of the inverter unit command signal from the unit command signal generation unit is corrected, and the two switching states of the corrected inverter unit command signals are converted into one command signal represented by the conduction ratio. Reversing the polarity of the other command signal represented by the current ratio with an offset,
By the pulse width modulation method based on the comparison result of the trapezoidal converter command signal from the converter command signal generation unit and the carrier signal from the carrier signal generation unit, the converter unit performs the three-phase operation. Converting an AC input voltage into the DC voltage;
The direct current converted by the converter unit by the inverter unit by a pulse width modulation method based on a comparison result between the command signal for the inverter unit corrected by the arithmetic unit and the carrier signal from the carrier signal generation unit. Converting the voltage into the predetermined three-phase AC output voltage,
In the step of generating the trapezoidal wave-shaped converter unit command signal by the converter unit command signal generation unit, the slope region of the trapezoidal wave-shaped converter unit command signal is:

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Or by using a table set in advance based on the predetermined formula, and the absolute value of the line current conduction ratio d _s ^* and the line current conduction The absolute value of the ratio d _t ^* represents the slope region of the trapezoidal command signal corresponding to two of the three phases of the three-phase AC input voltage, and the line current conduction ratio d _s ^*. , d _t ^*, the absolute value of the line current conduction ratio _dr ^* represents the slope region of the trapezoidal wave-shaped command signal corresponding to the remaining phase ,
When the absolute value of the line current conduction ratio d _s ^* is 1, | d _r ^* | = 1− | d _t ^* |, and when the absolute value of the line current conduction ratio d _t ^* is 1. Is | d _r ^* | = 1− | d _s ^* |, and when neither the absolute value of the line current conduction ratio d _s ^* nor the absolute value of d _t ^* is equal to 1, | d _r ^* | = 1 .

(ただし、ｄ_s ^*,ｄ_t ^*は通流比、位相角φは０≦φ≦π／３)
に基づいて生成することによって、複雑な演算により台形波状のコンバータ部用指令信号を形成する必要がなく、簡単な構成で制御部の演算負荷を低減できる。 According to the method for controlling the power converter, the three-phase AC output voltage (current) is not distorted with respect to the pulsating voltage (current) waveform of the DC voltage converted by the converter unit. By correcting the inverter unit command signal by the command signal correcting unit, the DC voltage converted by the converter unit is converted into a predetermined three-phase AC output voltage based on the corrected inverter unit command signal. It becomes possible. At this time, the command signal generation unit for the converter unit, the slope region of the trapezoidal converter command signal for the trapezoidal wave,

(Where d _s ^* and d _t ^* are the flow ratio, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Therefore, it is not necessary to form a trapezoidal wave command signal for the converter unit by complicated calculation, and the calculation load of the control unit can be reduced with a simple configuration.

(ただし、ｄ_s ^*,ｄ_t ^*は線電流通流比、位相角φは０≦φ≦π／３)
に基づいて生成することによって、簡単な構成で制御部の演算負荷を低減することができる。 As is clear from the above, according to the power conversion device and the method for controlling the power conversion device of the present invention, the slope region of the trapezoidal wave-shaped command signal used for the PWM modulation of the converter unit or the inverter unit,

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
The calculation load of the control unit can be reduced with a simple configuration.

  Further, according to the power conversion device of the present invention, the circuit of the control unit can be simplified by enabling PWM modulation with one carrier signal common to the converter unit and the inverter unit.

(ただし、０≦φ≦π／３)
で表される出力時間τ_rs,τ_rtの電流ベクトルに基づいて、上記コンバータ部用ＰＷＭ変調信号を生成することによって、簡単な構成で制御部の演算負荷を低減することができる。 Further, according to the power conversion device of the present invention, when using a voltage vector to output a DC voltage based on the space vector modulation scheme, when the carrier period is T ₀ and the phase angle φ,

(However, 0 ≦ φ ≦ π / 3)
By generating the converter PWM modulation signal based on the current vectors of the output times τ _rs , τ _rt represented by ## _EQU2 ## the calculation load of the control unit can be reduced with a simple configuration.

  Before describing the illustrated embodiment of the power conversion device and the power conversion device control method of the present invention, the features of the power conversion device and the power conversion device control method of the present invention will be described.

  First, in a power conversion device that performs DC / AC conversion, a sine wave voltage waveform is also sinusoidal in the same manner as a phase voltage waveform generation method that obtains a sinusoidal line voltage with respect to a constant DC voltage. Derivation of the phase voltage signal wave from which the wave output is obtained will be described.

  Technical reference 1 (Lixiang. Wei, Thomas. A. Lipo), “A Novel Matrix Converter Topology with Simple Commutation. ) '', I Triple E (IEEE IAS2001), vol.3, pp.1749-1754.2001), the direct conversion circuit with DC link is a current source converter, so the current ratio of the line current is trapezoidal Is controlling. In this specification, the voltage type is considered, and the duality of the current type and voltage type (line current: line voltage, phase current: corresponding to phase voltage) is considered, and the line voltage is trapezoidal. Shall be controlled.

This technical document 1 relates to a modulation system of a direct conversion circuit with a DC link that does not have a smoothing or rectifying circuit in the DC link unit. As shown in FIG. 3, the direct conversion circuit with a DC link of this technical document 1 includes six switching circuits S _ap , S _bp , S _cp , S _an , S _bn , S _cn constituting a three-phase bridge circuit. A converter unit and an inverter unit composed of six switching circuits S _up , S _vp , S _wp , S _un , S _vn , S _wn constituting a three-phase bridge circuit are provided. The converter unit converts the three-phase AC input voltages V _a , V _b , and V _c from the three-phase AC power sources V _sa , V _sb , and V _sc into direct current. The inverter unit converts the DC voltage V _dc converted by the converter unit into a three-phase AC output voltage V _su , V _sv , V _sw .

4 (a) to 4 (d) show the waveforms of the respective parts based on the control principle of the direct conversion circuit with a DC link in the above-mentioned technical document 1. FIG. As shown in FIG. 4 (a), the phase voltage corresponds to one of two states of [two phase: positive, one phase: negative] and [two phase: negative, one phase: positive]. It can be divided into six regions every 60 degrees. Here, Region 1 and Region 2 based on the c phase will be described. Here, in region 1, the c phase that is the minimum phase is made conductive by the switching circuit S _cn, and the following current ratio d is used by using the switching circuits S _ap and S _bp for the a phase and the b phase that are the maximum or intermediate phase. Switching with _ac and d _bc . In Similarly region 2, the c-phase is the maximum phase is made conductive by the switching circuit S _cp, an intermediate or a minimum phase a phase switching circuit b phase S _an,, the following flows ratio d using the S _bn Switching with _ac and d _bc .

  When the above operation is applied to six regions, the conduction ratio of each phase becomes a trapezoidal waveform as shown in FIG. Here, in order to show the switching state of the upper arm and the lower arm on the converter side, the upper arm is conducted when the conduction ratio is positive, and the lower arm is conducted when the conduction ratio is negative. .

で表され、ＤＣリンク電圧が脈流状の電圧波形となることが分かる。 At this time, as shown in FIG. 4 (c), the DC link voltage includes the line voltage Emax between the maximum phase and the minimum phase, and the intermediate phase between the minimum phase (region 1) and the maximum phase (region 2). It can be seen that two potentials of the line voltage Emid generated by the above are obtained. Also, by multiplying each DC link voltage by the current ratio, the average voltage V _dc is

It can be seen that the DC link voltage has a pulsating voltage waveform.

に基づき制御される。また、インバータの負荷は誘導性であるため電流源として捉えることができ、ＤＣリンク電流は通電時間が上式に示すように、脈流分ｃｏｓθ_inで振幅変調されているため、

で示されるように脈流状となる。ここで、上述のようにコンバータ側は一相が導通状態にあり、二相が各々の通流比ｄ_ac,ｄ_bcでスイッチングするため、領域１において入力電流は、

の関係となる。 On the other hand, on the inverter side, since voltage control is performed using the pulsating voltage V _dc , the energization time is multiplied by the pulsating current component cos θ _in so that the modulated wave compensates the pulsating current component,

It is controlled based on. Moreover, since the load of the inverter is inductive, it can be regarded as a current source, and the DC link current is amplitude-modulated by the pulsating current component cos θ _in as shown in the above equation.

As shown in FIG. Here, as described above, since one phase is in a conducting state on the converter side and two phases are switched at respective conduction ratios d _ac and d _bc , the input current in region 1 is

It becomes the relationship.

  As described above, since the waveform is obtained by multiplying the trapezoidal wave ratio and the pulsating current shown in FIG. 4B, the input current can be a sine wave shown in FIG.

  Further, as a line voltage control method for a constant DC voltage, a signal wave shown in Technical Document 2 (Japanese Patent Publication No. 6-081514) is known (right column, page 10, third column of Technical Document 2). (Refer to the description on the 25th line of the left column on page 4 and FIGS. 1 and 2).

で表される。この(１)式の相電圧指令信号Ｖ_u ^*,Ｖ_v ^*,Ｖ_w ^*に中間相電圧の１／２を加算することで、１相をπ／６遅れ、他の２相をπ／３進みの極性が相互に異なる相電圧指令信号Ｖ_u ^**,Ｖ_v ^**,Ｖ_w ^**は、

で表現される。上記技術文献２では、Ｖ_uv線間電圧の位相を基準に示しているが、ここでは、相電圧を基準とするため、相順を読み替えて表記している(WはU、UはV、VはW)。 Here, the phase voltage command signals V _u ^* , V _v ^* , V _w ^* are

It is represented by By adding 1/2 of the intermediate phase voltage to the phase voltage command signals V _u ^* , V _v ^* , V _w ^* of the equation (1), one phase is delayed by π / 6 and the other two phases are π / 3 Phase voltage command signals V _u ^** , V _v ^** , V _w ^** with mutually different polarities are

It is expressed by In the above-mentioned technical document 2, the phase of the V _uv line voltage is shown as a reference, but here, since the phase voltage is used as a reference, the phase order is replaced (W is U, U is V, V is W).

で表される。そして、位相角０〜π／３の領域では、線間電圧Ｖ_uwが最大値となるため、

の関係式が成り立つ。ここで、(４)式を(２)式に代入することにより、相電圧指令信号Ｖ_u ^**,Ｖ_v ^**,Ｖ_w ^**は、

で表される。 Moreover, since the pulsating voltage V _link is based on the voltage type, it is determined by the maximum value of the line voltage,

It is represented by And in the region of phase angle 0 to π / 3, the line voltage V _uw becomes the maximum value,

The following relational expression holds. Here, by substituting equation (4) into equation (2), the phase voltage command signals V _u ^** , V _v ^** , V _w ^**

It is represented by

When the command value is rewritten to a triangular wave carrier comparison base value of amplitude 1, the phase voltage command signals V _u ^** , V _v ^** , V _w ^** are expressed by the relationship between the carrier amplitude and the output voltage in the following equation (6): It can be rewritten as equation (8).

  The above results are the same as those obtained by dividing each phase command value by the maximum phase voltage in the line voltage control waveform shown in FIG. 5A. In the region where the phase angle is 0 to π / 3, the r phase is the maximum phase voltage. Become. FIG. 5B shows the result of the same calculation performed on six regions for each phase angle π / 3, and a trapezoidal wave modulation waveform (phase voltage) energized by 120 degrees.

(ただし、ｄ_s ^*,ｄ_t ^*は線電流通流比、位相角φは０≦φ≦π／３)
で表される所定の式を用いて生成するか、または、上記所定の式に基づいて予め設定されたテーブルを用いて生成することによって、簡単な構成で制御部の演算負荷を低減することができる。上記線電流通流比ｄ_s ^*の絶対値と線電流通流比ｄ_t ^*の絶対値が、三相交流入力電圧または三相交流出力電圧の３つの相のうちの２つの相に対応する台形波状の指令信号の傾斜領域を夫々表すと共に、線電流通流比ｄ_s ^*,ｄ_t ^*から決まる線電流通流比ｄ_r ^*の絶対値が、残りの相に対応する台形波状の指令信号の傾斜領域を表す。 Therefore, in the power conversion device and the method for controlling the power conversion device according to the present invention, the slope region of the trapezoidal wave-shaped command signal (the trapezoidal wave modulation waveform with 120-degree conduction) used for the PWM modulation of the converter unit or the inverter unit

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
The calculation load of the control unit can be reduced with a simple configuration by generating using a predetermined expression expressed by the above or using a table set in advance based on the predetermined expression it can. The absolute value of the line current conduction ratio d _s ^{* and} the absolute value of the line current conduction ratio d _t ^* correspond to two of the three phases of the three-phase AC input voltage or the three-phase AC output voltage. Each of the slope regions of the trapezoidal wave-shaped command signal is represented, and the absolute value of the line current flow ratio _dr ^* determined from the line current flow ratios _ds ^* and _dt ^* is a trapezoidal wave-shaped command corresponding to the remaining phases. Represents the slope region of the signal.

  Next, it is shown that the trapezoidal wave modulation waveform obtained as described above is equivalent to the line current command shown in the technical document 1. In the current type, the line current corresponds to the line voltage in the voltage type, so the line current command signal in FIG. 4B is compared with the trapezoidal wave modulation waveform (line voltage) in FIG. 5C.

で示されるが、領域１における０〜π／３の位相角で表記すると、

に書き換えられる。 In FIG. 4B, the b-phase line current command signal d _bc is

Is represented by a phase angle of 0 to π / 3 in region 1,

To be rewritten.

で表すことができ、(１０)式と等しいものとすると、(１１)式より、

が成り立てば良い。この(１２)式の右辺を、加法定理を用いて変形すると、

が成立する。 Further, when the line voltage command of FIG. 5C and the line current command signal of FIG.

If it is equal to equation (10), from equation (11)

Should be established. When the right side of equation (12) is transformed using the addition theorem,

Is established.

  Accordingly, the line voltage command signal generated by the control method of the power conversion device of the present invention is equivalent to the line current command shown in the technical document 1, so that, for example, the technical document 3 (Takashita Takeshita, two other authors, “ Voltage-type and current-type duality shown in Triangular wave comparison type PWM control of current-type three-phase inverter / converter ", Electrotechnical D, Vol.116, No.1,1996) (See Table 1 of Technical Document 3) By applying a logical operation based on the above, it is possible to easily generate a current type PWM pattern from a voltage type.

  Although the method for generating the phase voltage command signal has been described above, the PWM modulation method can be applied to a space vector modulation method power converter using a voltage vector in addition to a method using a triangular wave carrier signal.

The upper side of FIG. 6A is a vector diagram showing a space vector in PWM modulation of the space vector modulation method and a diagram for explaining a voltage vector in FIG. 5A. As shown in the vector diagram, the voltage vector is a non-zero vector in six states (V _{1 to} V ₆ ) out of eight states, and the remaining two states (V ₀ , V ₇ ) are zero states.

で表される。この位相角０〜π／３における電圧指令信号Ｖ_r ^*,Ｖ_s ^*,Ｖ_t ^*は、

で表される。図６Ａの下側は、図５Ａの線間電圧制御波形に位相角０〜π／３に対応する電圧ベクトルを示している。なお、図６Ａでは電圧制御率ｋsを０.５としている。ここで、位相角φが０〜π／３において電圧指令信号Ｖ_s ^*,Ｖ_t ^*の中間相電圧Ｖ_s ^* _{_mid}は、

で表される。図６Ｂに示すように、図５Ｂの台形波変調波形(相電圧)に位相角０〜π／３に対応する電圧ベクトルを示している。そして、空間ベクトル変調方式の基本式のτ₄／Ｔ₀とτ₆／Ｔ₀は、

で表される。この基本式を、図６Ａ中の表で位相角π／３毎に読み替えて、電圧ベクトルの出力時間を決定することによって、ＰＷＭ波形生成を行うことができる。 In this space vector modulation system, when the voltage vector output time τ ₀ , τ ₄ , τ ₆ at a phase angle φ of 0 to π / 3 and the voltage control rate is ks, the basic expression of the voltage vector is

It is represented by The voltage command signals V _r ^* , V _s ^* and V _t ^{* at} this phase angle 0 to π / 3 are

It is represented by The lower side of FIG. 6A shows a voltage vector corresponding to the phase angle 0 to π / 3 in the line voltage control waveform of FIG. 5A. In FIG. 6A, the voltage control rate ks is set to 0.5. Here, when the phase angle φ is 0 to π / 3, the intermediate phase voltage V _s ^* _{_mid} of the voltage command signals V _s ^* and V _t ^* is

It is represented by As shown in FIG. 6B, a voltage vector corresponding to a phase angle of 0 to π / 3 is shown in the trapezoidal wave modulation waveform (phase voltage) of FIG. 5B. And τ ₄ / T ₀ and τ ₆ / T ₀ in the basic formula of the space vector modulation method are

It is represented by The basic equation is read at every phase angle π / 3 in the table in FIG. 6A to determine the output time of the voltage vector, whereby the PWM waveform can be generated.

で表される。 As shown in FIG. 6C, the line voltage command signal V _st ^*

It is represented by

FIG. 7 shows the synchronous PWM modulation method disclosed in the above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 2004-266972) in comparison with the modulation method of Technical Document 1. In FIG. 7, t _s is the carrier period, I (rt) is the current command, I (st) is the current command, d _rt is Tsuryuhi, d _st is _{Tsuryuhi, I r, I s, I} t is an input Current, I _dc is a DC link current, V ₀ , V ₄ , V ₆ are voltage commands, d ₀ is a conduction ratio corresponding to the voltage command V ₀ , and d ₄ is a conduction ratio corresponding to the voltage command V _4. . V _u , V _v , and V _w are inverter gate signals.

  In FIG. 7, the carrier cycle on the converter side is divided into two switching states for energizing st and rt, and the current ratios are different from each other. Is used. Further, the signal wave to be compared with the carrier signal is corrected by the carrier amplitude by being multiplied by the current ratio of the converter. For this reason, the modulation circuit configuration is complicated as shown in Patent Document 1 (described in paragraphs [0021] to [0026] of FIG. 4 and FIG. 4).

On the other hand, FIG. 8 is a diagram showing a PWM modulation method using a triangular wave carrier signal of the power converter of the present invention. In FIG. 8, t _s is the carrier period, I (rt) is the current command, I (st) is the current command, d _rt is Tsuryuhi, d _st is _{Tsuryuhi, I r, I s, I} t is an input Current, I _dc is a DC link current, V ₀ , V ₄ , V ₆ are voltage commands, d ₀ is a conduction ratio corresponding to the voltage command V ₀ , and d ₄ is a conduction ratio corresponding to the voltage command V _4. . V _u , V _v and V _w are gate signals for the upper arm, and / V _u ′, / V _v ′ and / V _w ′ are gate signals for the lower arm.

  In FIG. 8, the same carrier signal is used for the converter side and the inverter side. Of the two command signals whose amplitudes are corrected as in the prior art, one command signal is offset and compared with the carrier signal. On the other hand, the polarity of the command signal is inverted and compared with the carrier signal, and the resulting gate signal is inverted. In addition, the gate signals in each period can be obtained as a gate signal having the same phase by taking a logical sum.

FIG. 9 is a diagram showing a PWM modulation method using a sawtooth carrier signal of the power converter of the present invention. In FIG. 9, t _s is the carrier period, I (rt) is the current command, I (st) is the current command, d _rt is the conduction ratio, d _st is the conduction ratio, and I _r , I _s , and I _t are input. Current, I _dc is a DC link current, V ₀ , V ₄ , V ₆ are voltage commands, d ₀ is a conduction ratio corresponding to the voltage command V ₀ , d ₄ is a conduction ratio corresponding to the voltage command V ₄ , d ₆ is a conduction ratio corresponding to the voltage command V ₆ . V _u , V _v and V _w are gate signals for the upper arm, and / V _u ′, / V _v ′ and / V _w ′ are gate signals for the lower arm.

The power conversion device shown in FIG. 9 can simplify carrier generation and modulation processing, and has a configuration more suitable for software. However, in the direct conversion circuit with a DC link shown in the technical document 1, in order to commutate the converter side in the zero vector period, it is necessary to use both V ₀ and V ₇ zero vectors. And it is disadvantageous in terms of loss. Further, as is generally known, the frequency of the sawtooth wave is f with respect to the triangular wave frequency 2f of the main component of the voltage spectrum by the carrier, and the noise side is also inferior.

  Thus, according to the power conversion device and the method for controlling the power conversion device of the present invention, the carrier comparison base that does not cause distortion in the line voltage (line current) with respect to the pulsating voltage (current) waveform. The phase voltage command waveform (or space vector modulation method) can reduce the calculation load when generating the command signal.

  Also, the modulation circuit can be simplified by enabling synchronous PWM modulation with a single carrier signal (such as a triangular wave or a sawtooth wave) common to the converter unit and the inverter unit.

  Hereinafter, a power conversion device and a method for controlling the power conversion device according to the present invention will be described in detail with reference to comparative examples and embodiments shown in the drawings.

[First Comparative Example]
FIG. 1 is a configuration diagram of a direct power converter with a direct current link of a first comparative example for explaining the power converter of the present invention. The direct power converter with a direct current link of the first comparative example does not have a smoothing filter in the direct current link portion that connects the converter portion and the inverter portion.

As shown in FIG. 1, the direct power converter includes a converter unit 1 composed of switches S _rp , S _rn , S _sp , S _sn , S _tp , _{St n} , and switches S _up , S _un , S _vp , The inverter unit 2 composed of S _vn , S _wp , S _wn , the switches S _rp , S _rn , S _sp , S _sn , S _tp , S _{tn of the} converter unit 1 and the switches S _up , S _un , And a control unit 3 that outputs a gate signal for _{turning on} and off S _vp , S _vn , S _wp , and S _wn . The switches S _rp , S _rn , S _sp , S _sn , S _tp , _{St n} and the switches S _up , S _un , S _vp , S _vn , S _wp , S _wn are each configured by combining a plurality of switching elements. Switching circuit.

The converter unit 1, a three-phase AC power supply enter the phase voltage v _r from (not shown) to one end of the one end and the switch S _rn of the switch S _rp, one end switch S of the phase voltage v _s of the switch S _sp enter at one end of the _sn, we have entered the phase voltage v _t at one end of the one end and the switch S _tn of the switch S _tp. The other _ends of the switches S _rp , S _sp , S _tp are connected to the first DC link portion L1, respectively, while the other _{ends of} the switches S _rn , S _sn , _{St n} are connected to the second DC link portion L2, respectively. Yes.

Further, the inverter section 2 connects the one ends and the switch S _un switches S _up to the output terminal of the phase voltage v _u of the three-phase AC output voltage, one end of the switch S _vp to the output terminal of the phase voltage v _v And one end of the switch S _vn are connected, and one end of the switch S _wp and one end of the switch S _wn are connected to the output terminal of the phase voltage v _w . The other _ends of the switches S _up , S _vp and S _wp are connected to the first DC link portion L1, respectively, while the other _ends of the switches S _un , S _vn and S _wn are connected to the second DC link portion L2, respectively. Yes.

Further, the control unit 3 generates trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* based on a power supply synchronization signal V _r as an example of a reference signal for synchronizing with a three-phase AC input voltage. A trapezoidal wave voltage command generation unit 11 as an example of a command signal generation unit and a converter unit command signal generation unit, and a trapezoidal wave voltage command signal V _r ^* , V _s ^* , from the trapezoidal wave voltage command generation unit 11, A comparison unit 12 for comparing V _t ^* and the carrier signal, a current source gate logic conversion unit 13 that outputs a gate signal based on the comparison result from the comparison unit 12, and the trapezoidal wave voltage command generation unit 11 Based on the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^{* from} the intermediate phase detector 14 for detecting the _conduction ratios d _rt , d _st , and the carrier signal generator for generating the carrier signal 15 and an output voltage indicator for the inverter 2 An output voltage command signal generator 21 as an example of an inverter command signal generator that generates the command signals V _u ^* , V _v ^* , V _w ^* , and an output voltage command signal from the output voltage command signal generator 21 Based on V _u ^* , V _v ^* , V _w ^* and the flow ratios d _rt , d _st from the intermediate phase detector 14,
d _rt + d _st V ^* (V ^* : voltage vector of each phase)
On the basis of the output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generation unit 21 and the _conduction ratio d _rt from the intermediate phase detection unit 14,
d _rt (1−V ^* ) (V ^* : voltage vector of each phase)
, A comparison unit 24 for comparing the calculation results from the calculation units 22 and 23 and the carrier signal, and a logical sum for outputting a gate signal based on the comparison result from the comparison unit 24 And an arithmetic unit 25.

Converter section 1 of the switch S _rp by the gate signal from the current-source gate logic converting section _{13, S rn, S sp,} S sn, S tp, with on-off control of the S _tn, the gate signal from the OR operation unit 25 Thus, the switches S _up , S _un , S _vp , S _vn , S _wp , and S _wn of the inverter unit 2 are turned on / off.

  The intermediate phase detection unit 14 and the calculation units 22 and 23 constitute a command signal correction unit. Further, the comparison unit 12 and the current source gate logic conversion unit 13 constitute a converter PWM modulation signal generation unit, and the comparison unit 24 and the OR operation unit 25 constitute an inverter PWM modulation signal generation unit. .

で表される相電圧指令信号Ｖ_u ^***,Ｖ_v ^***,Ｖ_w ^***と同様に、台形波状電圧指令信号Ｖ_r ^*,Ｖ_s ^*,Ｖ_t ^*の傾斜領域における値を予めテーブルとして設定しておく。ここで、位相角φは、三相交流入力電圧の相電圧ｖ_rに同期している。 The trapezoidal wave voltage command generation unit 11 generates a slope region of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* using a predetermined table. Here, the equation (8) described in FIGS. 5A to 5C, that is,

In the same way as the phase voltage command signals V _u ^*** , V _v ^*** , V _w ^*** represented by the values in the slope region of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* Are set in advance as a table. Here, the phase angle φ is synchronized with the phase voltage v _r of the three-phase AC input voltage.

Note that the slope regions of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , and V _t ^* may be obtained using equations instead of the table.

(ただし、位相角φは０≦φ≦π／３)

(ただし、位相角φはπ≦φ≦４π／３)
の所定の式を用いて、台形波状電圧指令信号Ｖ_r ^*,Ｖ_s ^*,Ｖ_t ^*の傾斜領域を夫々求める。これにより、演算負荷を低減しつつ、歪のない三相交流出力電圧(電流)を確実に得ることができる。 That is,

(However, the phase angle φ is 0 ≦ φ ≦ π / 3)

(However, phase angle φ is π ≦ φ ≦ 4π / 3)
The slope regions of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , and V _t ^* are obtained using the predetermined formulas (1). Thereby, it is possible to reliably obtain a three-phase AC output voltage (current) without distortion while reducing the calculation load.

According to the direct power converter with a DC link configured as described above, the three-phase AC output voltage (current) is distorted with respect to the pulsating voltage (current) waveform of the DC voltage converted by the converter unit 1. The output voltage command signal is corrected by the command signal correction unit (14, 22, 23) so that the DC voltage converted by the converter unit 1 is converted into a predetermined three voltage based on the corrected output voltage command signal. Convert to phase AC output voltage. At this time, the trapezoidal wave voltage command generation unit 11 generates the slope regions of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* by using a predetermined table (or a predetermined expression), The calculation load on the control unit can be reduced with a simple configuration.

  By enabling PWM modulation with one carrier signal common to the converter unit 1 and the inverter unit 2, the circuit of the control unit can be simplified.

[Second Comparative Example]
FIG. 2 is a configuration diagram of a matrix converter as an example of a direct power converter of a second comparative example for explaining the power converter of the present invention.

As shown in FIG. 2, the matrix converter includes a conversion unit 4 including switches S _ur , S _us , S _ut , S _vr , S _vs , S _vt , S _wr , S _ws , S _wt and the conversion unit 4. switches _{S ur, S us, S ut} , S vr, S vs, S vt, S wr, S ws, and a control unit 5 that outputs a gate signal for turning on and off the S _wt. The conversion unit 4 corresponds to a virtual converter unit and a virtual inverter unit, and does not have a smoothing filter in a virtual DC link unit that connects the virtual converter unit and the virtual inverter unit. The switches S _ur , S _us , S _ut , S _vr , S _vs , S _vt , S _wr , S _ws , and S _wt are switching circuits configured by combining a plurality of switching elements.

The conversion unit 4, the phase voltage v _r of the switch S _ur of the three-phase AC input voltage from the three-phase AC power supply 6, S _vr, enter into one end of the s S _wr respectively, of the three-phase AC input voltage The phase voltage v _s is input to one end of each of S _us , S _vs , and S _ws , and the phase voltage v _t of the three-phase AC input voltage is input to one end of each of S _ut , S _vt , and S _wt . The other _ends of the switches S _ur , S _us , S _ut are connected to the output terminal of the phase voltage v _u , respectively, while the other _{ends of} the switches S _vr , S _vs , S _vt are connected to the output terminal of the phase voltage v _r , respectively. The other _{ends of the} switches S _wr , S _ws , and S _wt are connected to the output terminal of the phase voltage v _w , respectively.

Further, the control unit 5 outputs trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* based on a power supply synchronization signal V _r as an example of a reference signal for synchronizing with a three-phase AC input voltage. A trapezoidal wave voltage command generation unit 31 as an example of a command signal generation unit and a converter unit command signal generation unit, and a trapezoidal wave voltage command signal V _r ^* , V _s ^* , from the trapezoidal wave voltage command generation unit 31. A comparison unit 32 for comparing V _t ^* and the carrier signal, a current source gate logic conversion unit 33 that outputs a gate signal based on the comparison result from the comparison unit 32, and the trapezoidal wave voltage command generation unit 31 Based on trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^{* from} the intermediate phase detector 34 for detecting the _conduction ratios d _rt , d _st , and the carrier signal generator for generating the carrier signal 35 and an output voltage command signal for the converter 4 An output voltage command signal generation unit 41 as an example of an inverter command signal generation unit that generates V _u ^* , V _v ^* , and V _w ^*, and an output voltage command signal V _u from the output voltage command signal generation unit 41 ^{Based on *} , V _v ^* , V _w ^* and the flow ratios d _rt , d _st from the intermediate phase detector 34,
d _rt + d _st V ^* (V ^* : voltage vector of each phase)
On the basis of the output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generation unit 41 and the _conduction ratio d _rt from the intermediate phase detection unit 34,
d _rt (1−V ^* ) (V ^* : voltage vector of each phase)
, A comparison unit 44 for comparing the calculation results from the calculation units 42 and 43 with the carrier signal, and a logical sum for outputting a gate signal based on the comparison result from the comparison unit 44 An arithmetic unit 45 and a gate signal synthesis unit 50 that synthesizes the gate signals based on the signal from the current source gate logic conversion unit 33 and the signal from the logical sum calculation unit 45 are provided.

The switches S _ur , S _us , S _ut , S _vr , S _vs , S _vt , S _wr , S _ws , and S _wt of the conversion unit 4 are on / off controlled by the gate signal from the gate signal synthesis unit 50.

  The intermediate phase detection unit 34 and the calculation units 42 and 43 constitute a command signal correction unit. The comparison unit 32 and the current source gate logic conversion unit 33 constitute a converter PWM modulation signal generation unit, and the comparison unit 44 and the OR operation unit 45 constitute an inverter PWM modulation signal generation unit. .

で表される相電圧指令信号Ｖ_u ^***,Ｖ_v ^***,Ｖ_w ^***と同様に、台形波状電圧指令信号Ｖ_r ^*,Ｖ_s ^*,Ｖ_t ^*の傾斜領域における値を予めテーブルとして設定しておく。ここで、位相角φは、三相交流入力電圧の相電圧ｖ_rに同期している。 The trapezoidal wave voltage command generation unit 31 generates a slope region of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* using a predetermined table. Here, the equation (8) described in FIGS. 5A to 5C, that is,

In the same way as the phase voltage command signals V _u ^*** , V _v ^*** , V _w ^*** represented by the values in the slope region of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* Are set in advance as a table. Here, the phase angle φ is synchronized with the phase voltage v _r of the three-phase AC input voltage.

Note that the slope regions of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , and V _t ^* may be obtained using equations instead of the table.

(ただし、位相角φは０≦φ≦π／３)

(ただし、位相角φはπ≦φ≦４π／３)
の所定の式を用いて、台形波状電圧指令信号Ｖ_r ^*,Ｖ_s ^*,Ｖ_t ^*の傾斜領域を夫々求める。これにより、演算負荷を低減しつつ、歪のない三相交流出力電圧(電流)を確実に得ることができる。 That is,

(However, the phase angle φ is 0 ≦ φ ≦ π / 3)

(However, phase angle φ is π ≦ φ ≦ 4π / 3)
The slope regions of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , and V _t ^* are obtained using the predetermined formulas (1). Thereby, it is possible to reliably obtain a three-phase AC output voltage (current) without distortion while reducing the calculation load.

According to the matrix converter having the above-described configuration, the pulsating voltage (current) waveform of the virtual DC voltage converted by the virtual converter unit is instructed not to cause distortion in the three-phase AC output voltage (current). The signal correcting unit (34, 42, 43) corrects the output voltage command signal, and based on the corrected output voltage command signal, the virtual inverter unit converts the virtual DC voltage converted by the virtual converter unit to a predetermined value. Convert to three-phase AC output voltage. At this time, the trapezoidal wave voltage command generation unit 31 generates the slope region of the trapezoidal wave voltage command signals V _r ^* , V _s ^* , V _t ^* by using a predetermined table (or a predetermined expression), The calculation load on the control unit can be reduced with a simple configuration.

  By enabling PWM modulation with one carrier signal common to the virtual converter unit and the virtual inverter unit, the circuit of the control unit can be simplified.

[First Embodiment]
FIG. 14 is a configuration diagram of a direct power converter with a DC link according to the first embodiment of the present invention. The direct power converter with a DC link of the first embodiment does not have a smoothing filter in the DC link unit that connects the converter unit and the inverter unit.

  The direct power converter of the first embodiment has the same configuration as the converter unit and the inverter unit of the direct power converter shown in FIG. 1 of the first comparative example except for the control unit. A converter part and an inverter part are abbreviate | omitted (FIG. 1 is used about a converter part and an inverter part).

Further, the control unit 103, based on the power supply synchronization signal V _r as one example of a reference signal for synchronizing the three-phase AC input voltage, trapezoidal line current command signal ^{_{d r *, d s *,}} d t * Trapezoidal wavy line current command generating unit 111 as an example of a command signal generating unit and a converter unit command signal generating unit, and a trapezoidal wavy line current command signal _dr ^* from the trapezoidal wavy line current command generating unit 111 d _s ^*, based on the d _t ^* and the power synchronization signal V _r, the carrier signal a, signal wave d _rpa corresponding to ^{_{B *, d rpb *, d}} rna *, a signal distribution unit 116 that outputs the d _rnb ^* , ^* the signal wave d _rpa from the signal distribution unit ^{_{116, d rpb *, d rna}} *, d rnb * and the carrier signal a, B (FIG. 14 "carrier a", "carrier B") and for comparing the Of the comparison unit 112 and a gate signal based on the comparison result from the comparison unit 112. A sum calculation unit 113, trapezoidal line current command signal d _r from the trapezoidal waveform line current instruction generation unit 111 ^*, d _s ^*, based on the d _t ^*, flowing ratio d _rt, detects the d _st 2 Phase command detection unit 114, carrier signal generation unit 115 that generates the carrier signals A and B, and inverter unit command that generates output voltage command signals V _u ^* , V _v ^* , and V _w ^* for the inverter unit 2 The output voltage command signal generation unit 121 as an example of the signal generation unit, the output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generation unit 121 and the two-phase command detection unit 114 Based on the flow ratios d _rt , d _st
d _rt + d _st V ^* (V ^* : voltage vector of each phase)
Based on the output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generation unit 121 and the _conduction ratio d _rt from the two-phase command detection unit 114. ,
d _rt (1−V ^* ) (V ^* : voltage vector of each phase)
, A comparison unit 124 for comparing the calculation results from the calculation units 122 and 123 and the carrier signal, and a logical sum for outputting a gate signal based on the comparison result from the comparison unit 124 And an arithmetic unit 125.

Switch S _rp converter section 1 by a gate signal from the OR operation unit _{113, S rn, S sp,} S sn, S tp, with on-off control of the S _tn, an inverter by the gate signal from the OR operation unit 125 The switches S _up , S _un , S _vp , S _vn , S _wp , S _wn of the unit 2 are turned on / off.

  The two-phase command detection unit 114 and the calculation units 122 and 123 constitute a command signal correction unit. The comparison unit 112 and the OR operation unit 113 constitute a converter PWM modulation signal generation unit, and the comparison unit 124 and the OR operation unit 125 constitute an inverter PWM modulation signal generation unit.

The trapezoidal corrugated line current command generation unit 111 generates a slope region of the trapezoidal corrugated line current command signals _dr ^* , _ds ^* , _dt ^* using a predetermined table.

ここで、ｄ_s ^*,ｄ_t ^*は線電流通流比であり、位相角φは０≦φ≦π／３である。また、位相角φは、三相交流入力電圧の相電圧ｖ_rに同期している。
例えば、先に示した技術文献３に示される電圧形,電流形の双対性に基づくと、電圧形インバータの線間電圧が電流形インバータの線電流に相当する。したがって、図５Ｃに示す台形波変調波形(線間電圧)が電流形インバータの線電流指令となるため、図５Ｂの台形波変調波形(相電圧)より、傾斜領域を求めることができる。
図５Ｂにおいて位相角０〜６０°の傾斜領域は、先に述べたように、次の(７)式,(８)式で表される。

なお、Ｖ _u ^*** ,Ｖ _v ^*** ,Ｖ _w ^*** は、図５Ｂのｒ相、ｓ相、ｔ相に相当する。
ここで、図５Ｃのｓｔ相がｓ相の線電流指令、ｔｒ相がｔ相の線電流指令に相当し、図５Ｂの相電圧波形より線間電圧を求めると、(７)式より

となり、上式を２で割って振幅１の波形に正規化すると、

先に示した(１１)式の関係となる。ここで、(７)式,(８)式を用いて示すと、

となる。そして、線間電圧は線電流に対してπ／６遅れ位相となることから、位相角を補正すると、図１０の領域１、領域４に相当する波形となり、全ての位相角について同様の演算を行うことで、上記|ｄ _s ^* |,|ｄ _t ^* |の式が導出される。
なお、この|ｄ _s ^* |,|ｄ _t ^* |波形は、先に(９)式〜(１３)式を用いて説明したように、技術文献１で示される線電流指令と等価である。 Here, based on the following equation, the values in the slope region of the trapezoidal wavy line current command signals _dr ^* , _ds ^* , _dt ^* are set in advance as a table.

Here, d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3. The phase angle φ is synchronized with the phase voltage v _r of the three-phase AC input voltage.
For example, based on the voltage-type and current-type duality shown in the above-mentioned Technical Document 3, the line voltage of the voltage-type inverter corresponds to the line current of the current-type inverter. Therefore, since the trapezoidal wave modulation waveform (line voltage) shown in FIG. 5C becomes a line current command of the current source inverter, the slope region can be obtained from the trapezoidal wave modulation waveform (phase voltage) of FIG. 5B.
In FIG. 5B, the inclined region having a phase angle of 0 to 60 ° is expressed by the following equations (7) and (8) as described above.

V _u ^*** , V _v ^*** , and V _w ^*** correspond to the r-phase, s-phase, and t-phase in FIG. 5B.
Here, the st phase in FIG. 5C corresponds to the s-phase line current command, the tr phase corresponds to the t-phase line current command, and the line voltage is obtained from the phase voltage waveform in FIG. 5B.

When the above equation is divided by 2 and normalized to a waveform of amplitude 1,

The relationship is the expression (11) shown above. Here, using equations (7) and (8),

It becomes. Since the line voltage has a π / 6 delayed phase with respect to the line current, if the phase angle is corrected, a waveform corresponding to region 1 and region 4 in FIG. 10 is obtained, and the same calculation is performed for all phase angles. By doing so, the expressions | d _s ^* | and | d _t ^* | are derived.
The | d _s ^* | and | d _t ^* | waveforms are equivalent to the line current command shown in Technical Document 1 as described above using the equations (9) to (13).

In addition, you may obtain | require the inclination area | region of trapezoidal wavy line current command signal _dr ^* , _ds ^* , _dt ^* using the said Formula instead of a table.

  FIG. 10 shows the line current conduction ratio when carrier comparison is used, FIG. 10 (a) shows the phase voltage waveform, and FIG. 10 (b) shows the line current conduction ratio waveform. For example, in the region of mode 1 shown in FIG. 10, the line current conduction ratio command is generated based on the above equation for the gradient region that is two-phase modulated.

Note that the trapezoidal waveform used here is equivalent to the line voltage waveform of the trapezoidal waveform voltage command signals V _r ^* , V _s ^* , V _t ^* of the first comparative example (from the relativity of the voltage type and current type). Equivalent to line current command).

Table 1 shows carrier signals to be compared for each mode. Since the sum of the two-phase command values (d _s ^* , d _t ^* ) is 1, the two phases are compared with different carrier signals. You can choose as you like. Here, the carrier signal A is selected by the rising waveform of the trapezoidal wave line current command signals _dr ^* , _ds ^* , _dt ^* , and the carrier signal B is selected by the falling waveform.

FIG. 11 shows a diagram for explaining the modulation scheme of Table 1. 11, from the top, flowing ratio command d _r ^*, instruction d _rp ^*, instruction d _rn ^*, signal distribution signal C _a, signal distribution signal C _b, signal wave d _rpa ^*, signal wave d _rpb ^*, signal wave d _rna ^*, signal wave d _rnb ^*, gate signal S _rp, shows a gate signal S _rn.

In the signal distributing part 116, flows ratio command d _r ^* of s sign husband command d _rp ^*, after separating the d _rn ^*, the waveform of the command value [pi / 2 phase advance signal distributed signals C _a, the C _b Based on this, signal waves d _rpa ^* , d _rpb ^* , d _rna ^* , d _rnb ^* corresponding to the carrier signals A, B to be compared are obtained. That is, the signal wave d _rpa ^* is obtained by a logical product of the command d _rp ^* and the signal distribution signal C _a, and the signal wave d _rpb ^* is obtained by a logical product of the command d _rp ^* and the signal distribution signal C _b. The signal wave d _rna ^* is obtained by a logical product of the command d _rn ^* and the signal distribution signal C _a, and the signal wave d _rnb ^* is obtained by a logical product of the command d _rn ^* and the signal distribution signal C _b. It is done.

The signal obtained here is compared with the two carrier signals A and B by the comparison unit 112 and then ORed by the OR operation unit 113 to obtain gate signals S _rp and S _rn for the upper and lower arms. . Similarly, the gate signals S _sp , S _sn , S _tp , and _{St n} are obtained for the flow ratio commands d _s ^* and d _t ^* . That is, the gate signal S _rp is obtained by a logical sum of the signal wave _drpa ^* and the signal wave d _rpb ^*, and the gate signal S _rn is obtained by a logical sum of the signal wave _drna ^* and the signal wave _drnb ^*. It is done.

に基づいて生成することによって、簡単な構成で制御部の演算負荷を低減することができる。 According to the direct power converter having the above configuration, the three-phase AC output voltage (current) is not distorted with respect to the pulsating voltage (current) waveform of the DC voltage converted by the converter unit 1. The command voltage correction unit (114, 122, 123) corrects the output voltage command signal, and based on the corrected output voltage command signal, the DC voltage converted by the converter unit 1 is output as a predetermined three-phase AC output. Convert to voltage. At this time, the trapezoidal corrugated line current command generation unit 111 determines the slope regions of the trapezoidal corrugated line current command signals _dr ^* , _ds ^* , _dt ^* ,

The calculation load of the control unit can be reduced with a simple configuration.

  Similarly, it can be realized by using space vector modulation. FIG. 12A shows a phase voltage waveform, FIG. 12B shows a line current conduction ratio waveform, and FIG. 13 shows a current source space. The current vector in the PWM modulation of the vector modulation method is shown.

Although the current vector shown in FIG. 13 is defined by the phase current, it is a trapezoidal wave signal wave, and one phase is in a conduction state for a period of 60 degrees. Therefore, as shown in FIG. On the basis of this, the phase current can be supplied by giving the energization time of each current vector as in the following equation.

  Table 2 shows the output time of each current vector in the PWM modulation of the current source space vector modulation method.

[Second Embodiment]
FIG. 15 is a configuration diagram of a matrix converter as an example of a direct power converter according to the second embodiment of the present invention.

The direct power converter of the second embodiment has the same configuration as the converter of the direct power converter shown in FIG. 2 of the second comparative example except for the controller, and in FIG. Omitted (FIG. 2 is used for the conversion unit).
The difference from the voltage type is that a two-phase modulation waveform is used for a one-phase modulation waveform in the synchronization of the virtual converter unit and the virtual inverter unit. The virtual converter unit side uses two phases of carrier signals, but differs in that a logic conversion unit from a phase current to a line current is not required to generate a gate signal.

Further, the control unit 205 is based on a power supply synchronization signal V _r as an example of a reference signal for synchronizing with a three-phase AC input voltage, and trapezoidal wave current command signals _dr ^* , _ds ^* , _dt ^*. A trapezoidal wavy line current command generation unit 231 as an example of a command signal generation unit and a converter unit command signal generation unit, and a trapezoidal wavy line current command signal _dr ^* , from the trapezoidal wavy line current command generation unit 231 d _s ^*, based on the d _t ^* and the power synchronization signal V _r, the carrier signal a, signal wave d _rpa corresponding to ^{_{B *, d rpb *, d}} rna *, a signal distribution unit 236 that outputs the d _rnb ^* , ^* the signal wave d _rpa from the signal distribution unit ^{_{236, d rpb *, d rna}} *, d rnb * and the carrier signal a, B (FIG. 15 "carrier a", "carrier B") and for comparing the The comparison unit 232 and the theory of outputting a gate signal based on the comparison result from the comparison unit 232 A sum calculation unit 233, trapezoidal line current command signal d _r from the trapezoidal waveform line current instruction generation unit 231 ^*, d _s ^*, based on the d _t ^*, flowing ratio d _rt, detects the d _st 2 Phase command detection unit 234, carrier signal generation unit 235 that generates the carrier signals A and B, and inverter unit command that generates output voltage command signals V _u ^* , V _v ^* , and V _w ^* for the conversion unit 4 An output voltage command signal generation unit 241 as an example of a signal generation unit, output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generation unit 241 and a two-phase command detection unit 234 Based on the flow ratios d _rt , d _st
d _rt + d _st V ^* (V ^* : voltage vector of each phase)
On the basis of the output voltage command signals V _u ^* , V _v ^* , V _w ^* from the output voltage command signal generator 241 and the _conduction ratio d _rt from the two-phase command detector 234. ,
d _rt (1−V ^* ) (V ^* : voltage vector of each phase)
, A comparison unit 244 for comparing the calculation results from the calculation units 242, 243 and the carrier signal, and a logical sum for outputting a gate signal based on the comparison result from the comparison unit 244 An arithmetic unit 245 and a gate signal synthesis unit 250 that synthesizes gate signals based on the signal from the logical sum computation unit 233 and the signal from the logical sum computation unit 245 are included.

On / off control of the switches S _ur , S _us , S _ut , S _vr , S _vs , S _vt , S _wr , S _ws , S _wt of the conversion unit 4 is performed by the gate signal from the gate signal synthesis unit 250.

  The two-phase command detection unit 234 and the calculation units 242, 243 constitute a command signal correction unit. The comparison unit 232 and the OR operation unit 233 constitute a converter PWM modulation signal generation unit, and the comparison unit 244 and the OR operation unit 245 constitute an inverter PWM modulation signal generation unit.

The trapezoidal corrugated line current command generation unit 231 generates a slope region of the trapezoidal corrugated line current command signals _dr ^* , _ds ^* , _dt ^* using a predetermined table.

Here, as in the first embodiment, the values of the trapezoidal wavy line current command signals _dr ^* , _ds ^* , _dt ^{* in} the inclined region are set in advance as a table.

In addition, you may obtain | require the inclination area | region of trapezoidal wavy line current command signal _dr ^* , _ds ^* , _dt ^* using the said Formula instead of a table.

に基づいて生成することによって、簡単な構成で制御部の演算負荷を低減することができる。 According to the matrix converter having the above-described configuration, the pulsating voltage (current) waveform of the virtual DC voltage converted by the virtual converter unit is instructed not to cause distortion in the three-phase AC output voltage (current). The signal correcting unit (234, 242, 243) corrects the output voltage command signal, and based on the corrected output voltage command signal, the virtual inverter unit converts the virtual DC voltage converted by the virtual converter unit to a predetermined value. Convert to three-phase AC output voltage. At this time, the trapezoidal wave voltage command generation unit 31 determines the slope regions of the trapezoidal wave line current command signals _dr ^* , _ds ^* , _dt ^* ,

The calculation load of the control unit can be reduced with a simple configuration.

In the first and second embodiments described above, the direct-type power conversion device in which the trapezoidal wave voltage command signal and the trapezoidal wave current command signal obtained from the slope area using a table or equation are applied to the converter side has been described. You may apply this invention to the power converter device which applied the trapezoidal wave-shaped command signal to the inverter side.
As a power converter,
A command signal generator that generates a trapezoidal command signal based on the phase angle of the reference signal;
A carrier signal generator for generating a carrier signal;
Based on the trapezoidal wave-shaped command signal from the command signal generator and the carrier signal generated by the carrier signal generator, the three-phase AC input voltage is converted into a DC voltage, or the DC voltage is converted into a three-phase voltage. A conversion unit for converting to an AC output voltage,
The command signal generation unit may generate the slope region of the trapezoidal command signal using a predetermined table or a predetermined formula.

  Here, the reference signal when generating the trapezoidal wave-shaped command signal by the command signal generation unit is the reference of the three-phase AC input voltage when the conversion unit converts the three-phase AC input voltage into the DC voltage. When the converter converts the DC voltage into a three-phase AC output voltage, for example, a signal serving as a reference for generating the three-phase AC output voltage is used.

  According to the power conversion device having the above-described configuration, the command signal generation unit generates the slope region of the trapezoidal wave-shaped command signal using a predetermined table or a predetermined formula, thereby performing a trapezoidal wave-shaped command by a complicated calculation. There is no need to form a signal, and the calculation load on the control unit can be reduced with a simple configuration.

As a power converter,
A converter unit that converts a three-phase AC input voltage into a DC voltage; and an inverter unit that converts the DC voltage converted by the converter unit into a predetermined three-phase AC output voltage. The converter unit and the inverter unit A power converter that does not have a smoothing filter in the DC link part connecting
A command signal generation unit for a converter unit that generates a trapezoidal converter command signal in synchronization with the three-phase AC input voltage;
A carrier signal generator for generating a carrier signal;
An inverter command signal generator for generating an inverter command signal for outputting the predetermined three-phase AC output voltage;
A command signal correction unit that corrects the inverter unit command signal generated by the inverter unit command signal generation unit based on the trapezoidal converter unit command signal from the converter unit command signal generation unit; Prepared,
The converter unit converts the three-phase AC input voltage into the DC voltage based on the trapezoidal converter unit command signal from the converter unit command signal generation unit and the carrier signal from the carrier signal generation unit. Converted,
The inverter unit converts the DC voltage converted by the converter unit into the predetermined three-phase AC output voltage based on the inverter unit command signal corrected by the command signal correction unit,
The converter unit command signal generation unit may generate the slope region of the trapezoidal converter unit command signal using a predetermined table or a predetermined formula.

  According to the power conversion device having the above configuration, for the pulsating voltage (current) waveform of the DC voltage converted by the converter unit, the three-phase AC output voltage (current) is not distorted. By correcting the inverter unit command signal by the command signal correcting unit, the DC voltage converted by the converter unit is converted into a predetermined three-phase AC output voltage based on the corrected inverter unit command signal. Is possible. At this time, the converter unit command signal generation unit generates a slope region of the trapezoidal converter unit command signal by using a predetermined table or a predetermined formula, thereby performing a trapezoidal converter unit by a complicated calculation. It is not necessary to form a command signal for operation, and the calculation load on the control unit can be reduced with a simple configuration.

(ただし、位相角φは０≦φ≦π／３)

(ただし、位相角φはπ≦φ≦４π／３)
としてもよい。 In the above power converter,
The predetermined formula is

(However, the phase angle φ is 0 ≦ φ ≦ π / 3)

(However, phase angle φ is π ≦ φ ≦ 4π / 3)
It is good.

  According to the power conversion device, the converter unit command signal generation unit generates a trapezoidal converter unit command signal using the predetermined formula, thereby reducing the computation load and reducing distortion. A phase AC output voltage (current) can be obtained with certainty.

In the above power converter,
The PWM modulation signal generation unit for converter unit that generates the PWM modulation signal for converter unit by comparing the command signal for converter unit from the command signal generation unit for converter unit and the carrier signal from the carrier signal generation unit When,
The inverter part PWM that generates the inverter part PWM modulation signal by comparing the inverter part command signal from the inverter part command signal generation part with the same carrier signal used in the converter part A modulation signal generator,
The converter unit converts the three-phase AC input voltage into the DC voltage based on the converter unit PWM modulation signal generated by the converter unit PWM modulation signal generation unit,
The inverter unit converts the DC voltage converted by the converter unit into the predetermined three-phase AC output voltage based on the PWM modulation signal for the inverter unit generated by the PWM modulation signal generation unit for the inverter unit. May be.

  According to the power conversion device, the circuit of the control unit can be simplified by enabling PWM modulation with one carrier signal common to the converter unit and the inverter unit.

  In the power converter, the carrier signal may be a triangular wave signal.

  According to the above power converter, a circuit for pulse width modulation can be simplified by using a triangular wave signal suitable for PWM modulation as a carrier signal.

  In the power converter, the carrier signal may be a sawtooth signal.

  According to the above power converter, carrier generation and modulation processing can be simplified by using a sawtooth signal as a carrier signal.

In the above power converter,
The converter part
Three switching circuits in which each phase voltage of the three-phase AC input voltage is input to one end and the other end is connected to the first DC link unit,
Each phase voltage of the three-phase AC input voltage is respectively input to one end, and has three switching circuits each connected to the second DC link portion and the other end.
The inverter part is
Three switching circuits in which each output terminal of the predetermined three-phase AC output voltage is connected to one end, and the other end is connected to the first DC link unit;
Each of the output terminals of the predetermined three-phase AC output voltage may be connected to one end, and the switching terminal may have three switching circuits each having the other end connected to the second DC link unit.

In the above power converter,
A matrix converter having a virtual converter unit corresponding to the converter unit, a virtual inverter unit corresponding to the inverter unit, and a virtual DC link unit corresponding to the DC link unit,
The virtual converter unit and the virtual inverter unit are
Three switching circuits in which the first phase voltage of the three-phase AC input voltage is respectively input to one end, and the other end is connected to each output terminal of the predetermined three-phase AC output voltage;
Three switching circuits in which the second phase voltage of the three-phase AC input voltage is respectively input to one end, and the other end is connected to each output terminal of the predetermined three-phase AC output voltage;
A third phase voltage of the three-phase AC input voltage is input to one end, and three switching circuits are connected to the output terminals of the predetermined three-phase AC output voltage. Good.

As a power converter,
A command signal generator for the converter unit that generates a command signal for the converter unit synchronized with the three-phase AC input voltage;
An inverter command signal generator for generating an inverter command signal for outputting a predetermined three-phase AC output voltage;
A carrier signal generator for generating a carrier signal;
A converter unit that converts the three-phase AC input voltage into a DC voltage based on the converter unit command signal from the converter unit command signal generation unit and the carrier signal generated by the carrier signal generation unit;
Based on the inverter part command signal from the inverter part command signal generation part and the same carrier signal used in the converter part, the DC voltage converted by the converter part is converted into the predetermined three It may have an inverter part which converts into a phase alternating current output voltage.

  According to the power conversion device having the above configuration, the circuit of the control unit can be simplified by enabling PWM modulation with one carrier signal common to the converter unit and the inverter unit.

  In the power converter, the carrier signal may be a triangular wave signal.

  According to the above power converter, a circuit for pulse width modulation can be simplified by using a triangular wave signal suitable for PWM modulation as a carrier signal.

  In the power converter, the carrier signal is a sawtooth signal.

  According to the above power converter, carrier generation and modulation processing can be simplified by using a sawtooth signal as a carrier signal.

In addition, as a method for controlling the power converter,
Generating a trapezoidal command signal by the command signal generator;
Generating a carrier signal by a carrier signal generator;
Based on the trapezoidal wave-shaped command signal from the command signal generator and the carrier signal generated by the carrier signal generator, the converter converts the three-phase AC input voltage into a DC voltage, or DC Converting the voltage into a three-phase AC output voltage,
In the step of generating the trapezoidal wave-shaped command signal by the command signal generation unit, the slope region of the trapezoidal wave-shaped command signal may be generated using a predetermined table or a predetermined formula.

  According to the control method of the power converter, the command signal generation unit generates a slope region of the trapezoidal converter command signal using a predetermined table or a predetermined formula, thereby performing a complicated calculation. There is no need to form a trapezoidal command signal, and the calculation load on the control unit can be reduced with a simple configuration.

In addition, as a method for controlling the power converter,
A converter unit that converts a three-phase AC input voltage into a DC voltage; and an inverter unit that converts the DC voltage converted by the converter unit into a predetermined three-phase AC output voltage. The converter unit and the inverter unit A method of controlling a power converter that does not have a smoothing filter in a DC link unit connecting
Generating a trapezoidal converter command signal for the converter unit synchronized with the three-phase AC input voltage by the converter command signal generation unit;
Generating a carrier signal by a carrier signal generator;
Generating an inverter unit command signal for outputting the predetermined three-phase AC output voltage by the inverter unit command signal generation unit;
A step of correcting the command signal for the inverter unit generated by the command signal generating unit for the inverter unit by the command signal correcting unit based on the command signal for the converter part of the trapezoidal wave from the command signal generating unit for the converter unit When,
Based on the trapezoidal converter command signal from the converter command signal generator and the carrier signal from the carrier signal generator, the converter unit converts the three-phase AC input voltage to the DC voltage. Converting, and
Based on the inverter unit command signal corrected by the command signal correction unit, the inverter unit converting the DC voltage converted by the converter unit into the predetermined three-phase AC output voltage. And
In the step of generating the trapezoidal converter command signal by the converter unit command signal generating unit, the slope region of the trapezoidal converter unit command signal is generated using a predetermined table or a predetermined formula. It may be characterized by that.

  According to the method for controlling the power converter, the three-phase AC output voltage (current) is not distorted with respect to the pulsating voltage (current) waveform of the DC voltage converted by the converter unit. By correcting the inverter unit command signal by the command signal correcting unit, the DC voltage converted by the converter unit is converted into a predetermined three-phase AC output voltage based on the corrected inverter unit command signal. It becomes possible. At this time, the converter unit command signal generation unit generates a slope region of the trapezoidal converter unit command signal by using a predetermined table or a predetermined formula, thereby performing a trapezoidal converter unit by a complicated calculation. It is not necessary to form a command signal for operation, and the calculation load on the control unit can be reduced with a simple configuration.

(ただし、位相角φは０≦φ≦π／３)

(ただし、位相角φはπ≦φ≦４π／３)
としてもよい。 Moreover, in the control method of the power converter,
The predetermined formula is

(However, the phase angle φ is 0 ≦ φ ≦ π / 3)

(However, phase angle φ is π ≦ φ ≦ 4π / 3)
It is good.

  According to the method for controlling the power converter, the converter unit command signal generation unit generates a trapezoidal converter unit command signal using the predetermined formula, thereby reducing the computation load and reducing distortion. A three-phase AC output voltage (current) with no noise can be obtained with certainty.

In addition, as a method for controlling the power converter,
A step of generating a command signal for the converter unit synchronized with the three-phase AC input voltage by the command signal generating unit for the converter unit;
Generating an inverter unit command signal for outputting a predetermined three-phase AC output voltage by the inverter unit command signal generating unit;
Generating a carrier signal by a carrier signal generator;
Based on the converter unit command signal from the converter unit command signal generation unit and the carrier signal generated by the carrier signal generation unit, the converter unit converts the three-phase AC input voltage to a DC voltage; ,
Based on the inverter part command signal from the inverter part command signal generation part and the same carrier signal used in the converter part, the DC voltage converted by the converter part is converted into the predetermined three And a step of converting the phase AC output voltage into an AC output voltage by an inverter unit.

  According to the method for controlling the power converter, the circuit of the control unit can be simplified by enabling PWM modulation with one carrier signal common to the converter unit and the inverter unit.

(ただし、０≦φ≦π／３)
で表される出力時間τ₄,τ₆の電圧ベクトルに基づいて、上記ＰＷＭ変調信号を生成することを特徴とするものでもよい。 As a power converter,
A PWM modulation signal generator for generating a PWM modulation signal by a space vector modulation method;
Based on the PWM modulation signal from the PWM modulation signal generation unit, a three-phase AC input voltage is converted into a DC voltage, or a conversion unit that converts a DC voltage into a three-phase AC output voltage,
The PWM modulation signal generation unit uses a voltage vector to be output based on the space vector modulation method, and when the carrier period is T ₀ and the phase angle φ,

(However, 0 ≦ φ ≦ π / 3)
The PWM modulation signal may be generated based on voltage vectors of output times τ ₄ and τ ₆ expressed by

(ただし、０≦φ≦π／３)
で表される出力時間τ₄,τ₆の電圧ベクトルに基づいて、ＰＷＭ変調信号を生成することによって、複雑な演算により指令信号を形成する必要がなく、簡単な構成で制御部の演算負荷を低減できる。 According to the power conversion device having the above configuration, when the command signal generation unit uses a voltage vector to be output based on the space vector modulation method, the carrier period is T ₀ , and the phase angle φ,

(However, 0 ≦ φ ≦ π / 3)
By generating the PWM modulation signal based on the voltage vectors of the output times τ ₄ and τ ₆ expressed by the following, it is not necessary to form a command signal by complicated calculation, and the calculation load of the control unit can be reduced with a simple configuration. Can be reduced.

(ただし、０≦φ≦π／３)
で表される出力時間τ₄,τ₆の電圧ベクトルに基づいて、上記コンバータ部用ＰＷＭ変調信号を生成することを特徴とするものでもよい。 As a power converter,
A converter unit that converts a three-phase AC input voltage into a DC voltage; and an inverter unit that converts the DC voltage converted by the converter unit into a predetermined three-phase AC output voltage. The converter unit and the inverter unit A power converter that does not have a smoothing filter in the DC link part connecting
A PWM modulation signal generation unit for a converter unit that generates a PWM modulation signal for the converter unit synchronized with the three-phase AC input voltage by a space vector modulation method;
A PWM modulation signal generating unit for inverter that generates a PWM modulation signal for inverter for outputting the predetermined three-phase AC output voltage;
A PWM modulation signal correction unit for correcting the PWM modulation signal for the inverter unit generated by the PWM modulation signal generation unit for the inverter unit based on the PWM modulation signal for the converter unit from the PWM modulation signal generation unit for the converter unit And
The converter unit converts the three-phase AC input voltage into the DC voltage based on the PWM modulation signal for the converter unit from the PWM modulation signal generation unit for the converter unit,
The inverter unit converts the DC voltage converted by the converter unit into the predetermined three-phase AC output voltage based on the PWM modulation signal for the inverter unit corrected by the PWM modulation signal correction unit,
The PWM modulation signal generation unit for the converter unit uses a voltage vector to output the DC voltage based on the space vector modulation method, and when the carrier period is T ₀ and the phase angle φ,

(However, 0 ≦ φ ≦ π / 3)
The converter unit PWM modulation signal may be generated based on the voltage vectors of the output times τ ₄ and τ ₆ expressed by

(ただし、０≦φ≦π／３)
で表される出力時間τ₄,τ₆の電圧ベクトルに基づいて、コンバータ部用ＰＷＭ変調信号を生成することによって、複雑な演算により指令信号を形成する必要がなく、簡単な構成で制御部の演算負荷を低減できる。 According to the power conversion device having the above configuration, for the pulsating voltage (current) waveform of the DC voltage converted by the converter unit, the three-phase AC output voltage (current) is not distorted. Based on the inverter unit command signal corrected by the command signal correcting unit, the DC voltage converted by the converter unit is converted into a predetermined three-phase AC output voltage. At this time, when the converter unit command signal generation unit uses the voltage vector to output the DC voltage based on the space vector modulation method, the carrier cycle is T ₀ , and the phase angle φ,

(However, 0 ≦ φ ≦ π / 3)
By generating the PWM modulation signal for the converter unit based on the voltage vectors of the output times τ ₄ and τ ₆ expressed as follows, it is not necessary to form a command signal by complicated calculation, and the control unit can be configured with a simple configuration. Calculation load can be reduced.

FIG. 1 is a block diagram of a direct power converter according to a first comparative example of the present invention. FIG. 2 is a configuration diagram of a direct power converter according to a second comparative example of the present invention. FIG. 3 is a configuration diagram of a direct conversion circuit with a DC link. FIG. 4 is a diagram showing waveforms at various parts for explaining the control principle of the direct conversion circuit with a DC link. FIG. 5A is a diagram showing a line voltage control waveform. FIG. 5B is a diagram showing a trapezoidal wave modulation waveform (phase voltage). FIG. 5C is a diagram showing a trapezoidal wave modulation waveform (line voltage). FIG. 6A is a diagram for explaining space vector modulation. FIG. 6B is a diagram showing a trapezoidal wave modulation waveform (phase voltage) in space vector modulation. FIG. 6C is a diagram showing a trapezoidal wave modulation waveform (line voltage) in space vector modulation. FIG. 7 is a diagram showing a synchronous PWM modulation method for comparison. FIG. 8 is a diagram showing a PWM modulation method using a triangular wave carrier signal of the direct power converter of the present invention. FIG. 9 is a diagram showing a PWM modulation method using a sawtooth carrier signal of the direct power converter according to the present invention. FIG. 10 is a diagram showing a line current conduction ratio when carrier comparison is used. FIG. 11 is a diagram for explaining the modulation scheme of Table 1. FIG. 12 is a diagram showing a line current conduction ratio when space vector modulation is used. FIG. 13 is a diagram for explaining space vector modulation. FIG. 14 is a configuration diagram of a direct power converter with a DC link according to the first embodiment of the present invention. FIG. 15 is a configuration diagram of a matrix converter as an example of a direct power converter according to the second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Converter part 2 ... Inverter part 3 ... Control part 4 ... Conversion part 5 ... Control part 11 ... Trapezoid wave-shaped voltage command generation part 12 ... Comparison part 13 ... Current source gate logic conversion part 14 ... Intermediate phase detection part 15 ... Carrier signal Generation unit 21 ... Output voltage command signal generation unit 22 ... Calculation unit 23 ... Calculation unit 24 ... Comparison unit 25 ... Logical sum calculation unit 31 ... Trapezoidal wave voltage command generation unit 32 ... Comparison unit 33 ... Current source gate logic conversion unit 34 ... Intermediate phase detection unit 35 ... carrier signal generation unit 41 ... output voltage command signal generation unit 42 ... calculation unit 43 ... calculation unit 44 ... comparison unit 45 ... OR operation unit 50 ... gate signal synthesis unit 11 ... trapezoidal wave line current command generation Unit 12 ... Comparison unit 103 ... Control unit 113 ... OR operation unit 114 ... Two-phase command detection unit 115 ... Carrier signal generation unit 116 ... Signal distributor 121 ... Output voltage command signal generation unit 12 DESCRIPTION OF SYMBOLS 2 ... Operation part 123 ... Operation part 124 ... Comparison part 125 ... Logical sum operation part 203 ... Control part 231 ... Trapezoid wave current command generation part 232 ... Comparison part 233 ... Logical sum operation part 234 ... Two-phase command detection part 235 ... Carrier signal generator 236 ... signal distributor 241 ... output voltage command signal generator 242 ... calculator 243 ... calculator 244 ... comparator 245 ... logical sum calculator 250 ... gate signal combiner

Claims (4)

A converter unit (1) that converts a three-phase AC input voltage into a DC voltage, and an inverter unit (2) that converts the DC voltage converted by the converter unit (1) into a predetermined three-phase AC output voltage. A power conversion device that does not have a smoothing filter in a DC link unit that connects the converter unit (1) and the inverter unit (2),
A converter unit command signal generation unit (111, 231) for generating a trapezoidal converter unit command signal based on a phase angle of a reference signal generated in synchronization with the three-phase AC input voltage;
A carrier signal generator (115, 235) for generating a carrier signal;
An inverter command signal generator (121, 241) for generating an inverter command signal for outputting the predetermined three-phase AC output voltage;
The trapezoidal converter unit command signal from the converter unit command signal generation unit (111, 231) is a three-phase command signal represented by a phase voltage, and is one of the three-phase command signals. A two-phase command detection unit (114, 234) for detecting a conduction ratio of other two-phase command signals that are switched when the phase command signal indicates a conduction state;
The communication from the two-phase command detection unit (114, 234) so that the inverter unit (2) can perform pulse width modulation using the same carrier signal as that used in the converter unit (1). Based on the flow ratio, the amplitude of the inverter command signal from the inverter command signal generator (121, 241) is corrected, and two switching states of the corrected inverter command signal are corrected. An arithmetic unit (122, 123, 242, 243) that reverses the polarity of the other command signal represented by the flow ratio by giving an offset to one command signal represented by the flow ratio, and <br / >
The converter unit (1) is configured such that the trapezoidal converter unit command signal from the converter unit command signal generation unit (111, 231) and the carrier signal from the carrier signal generation unit (115, 235). By the pulse width modulation method based on the comparison result, the three-phase AC input voltage is converted to the DC voltage,
The inverter unit (2) compares the inverter unit command signal corrected by the arithmetic unit (122, 123, 242, 243) and the carrier signal from the carrier signal generation unit (115, 135). The DC voltage converted by the converter unit (1) is converted into the predetermined three-phase AC output voltage by a pulse width modulation method based on
The converter unit command signal generation unit (111, 231) is configured to determine the slope region of the trapezoidal converter unit command signal.

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Or by using a table set in advance based on the predetermined formula, and the absolute value of the line current conduction ratio d _s ^* and the line current conduction The absolute value of the ratio d _t ^* represents the slope region of the trapezoidal command signal corresponding to two of the three phases of the three-phase AC input voltage, and the line current conduction ratio d _s ^*. , d _t ^*, the absolute value of the line current conduction ratio _dr ^* represents the slope region of the trapezoidal wave-shaped command signal corresponding to the remaining phase ,
When the absolute value of the line current conduction ratio d _s ^* is 1, | d _r ^* | = 1− | d _t ^* |, and when the absolute value of the line current conduction ratio d _t ^* is 1. Is | d _r ^* | = 1− | d _s ^* |, and when neither the absolute value of the line current conduction ratio d _s ^* nor the absolute value of d _t ^* is equal to 1, | d _r ^* | = 1, a power conversion device. The power conversion device according to claim 1 ,
The converter unit that generates the PWM modulation signal for the converter unit by comparing the converter unit command signal from the converter unit command signal generation unit (111) with the carrier signal from the carrier signal generation unit (115). PWM modulation signal generator (112, 113) for
An inverter that generates a PWM modulation signal for an inverter unit by comparing the inverter unit command signal from the inverter unit command signal generation unit (121) with the same carrier signal used in the converter unit Part PWM modulation signal generator (124, 125),
The converter unit (1) converts the three-phase AC input voltage into the DC voltage based on the converter unit PWM modulation signal generated by the converter unit PWM modulation signal generation unit (112, 113).
The inverter unit (2) includes the DC voltage converted by the converter unit (1) based on the inverter unit PWM modulation signal generated by the inverter unit PWM modulation signal generation unit (124, 125). Is converted to the predetermined three-phase AC output voltage,
The converter part (1)
Three switching circuits (S _rp , S _sp , S _tp ) in which each phase voltage of the three-phase AC input voltage is input to one end and the other end is connected to the first DC link unit;
Each phase voltage of the three-phase AC input voltage is input to one end, and three switching circuits (S _rn , S _sn , _{St n} ) each having the other end connected to the second DC link unit,
The inverter part (2)
Three switching circuits (S _up , S _vp , S _wp ) in which each output terminal of the predetermined three-phase AC output voltage is connected to one end, and the other end is connected to the first DC link unit;
Each output terminal of the predetermined three-phase AC output voltage is connected to one end, and three switching circuits (S _un , S _vn , S _wn ) are connected to the second DC link part, respectively. The power converter characterized by the above-mentioned. The power conversion device according to claim 1 ,
A converter unit for generating a PWM modulation signal for a converter unit by comparing the converter unit command signal from the converter unit command signal generation unit (231) with the carrier signal from the carrier signal generation unit (235). PWM modulation signal generator (232, 233) for
An inverter that generates a PWM modulation signal for an inverter unit by comparing the inverter unit command signal from the inverter unit command signal generation unit (241) with the same carrier signal used in the converter unit Part PWM modulation signal generator (244, 245),
A matrix converter having a virtual converter unit corresponding to the converter unit, a virtual inverter unit corresponding to the inverter unit, and a virtual DC link unit corresponding to the DC link unit,
The virtual converter unit and the virtual inverter unit are
Of the three-phase AC input voltage, a first phase voltage is input to one end, and three switching circuits ( _Sur , _Svr) each having the other end connected to each output terminal of the predetermined three-phase AC output voltage. , S _wr )
Of the three-phase AC input voltage, a second phase voltage is input to one end, and three switching circuits (S _us , S _vs , each having the other end connected to each output terminal of the predetermined three-phase AC output voltage. , S _ws ) and
Three switching circuits (S _ut , S _vt) in which the third phase voltage of the three-phase AC input voltage is input to one end and the other end is connected to each output terminal of the predetermined three-phase AC output voltage. , S _wt )
The converter PWM modulation signal generated by the converter PWM modulation signal generator (232, 233) and the inverter PWM modulation signal generated by the inverter PWM modulation signal generator (244, 245). And converting the three-phase AC input voltage into the predetermined three-phase AC output voltage. A converter unit (1) that converts a three-phase AC input voltage into a DC voltage, and an inverter unit (2) that converts the DC voltage converted by the converter unit (1) into a predetermined three-phase AC output voltage. A control method for a power conversion device that does not have a smoothing filter in a DC link unit connecting the converter unit (1) and the inverter unit (2),
Generating a trapezoidal wave command signal for the converter unit by the converter command signal generation unit (111, 231) based on the phase angle of the reference signal generated so as to be synchronized with the three-phase AC input voltage;
Generating a carrier signal by the carrier signal generator (115, 235);
Generating an inverter command signal for outputting the predetermined three-phase AC output voltage by the inverter command signal generator (121, 241);
The trapezoidal converter unit command signal from the converter unit command signal generation unit (111, 231) is a three-phase command signal represented by a phase voltage, and is one of the three-phase command signals. Detecting a current ratio of other two-phase command signals that are switched when the phase command signal indicates a conduction state by the two-phase command detection unit (114, 234);
In order to enable pulse width modulation using the same carrier signal as that used in the converter unit (1) in the inverter unit (2), the flow from the intermediate phase detection unit (114, 234) is possible. Based on the ratio, the operation unit (122, 123, 242, 243) corrects the amplitude of the inverter unit command signal from the inverter unit command signal generation unit (121, 241), and the corrected inverter Inversion of the polarity of the other command signal represented by the conduction ratio by giving an offset to one command signal represented by the conduction ratio for two switching states of the part command signal;
Pulse width modulation system based on the comparison result between the trapezoidal converter command signal from the converter command signal generator (111, 231) and the carrier signal from the carrier signal generator (115, 235) The converter unit (1) converts the three-phase AC input voltage into the DC voltage;
By a pulse width modulation method based on a comparison result between the inverter unit command signal corrected by the arithmetic unit (122, 123, 242, 243) and the carrier signal from the carrier signal generation unit (115, 135), Converting the DC voltage converted by the converter unit (1) into the predetermined three-phase AC output voltage by the inverter unit (2),
In the step of generating the trapezoidal converter command signal by the converter unit command signal generator (111, 231), the slope region of the trapezoidal converter command signal is

(Where d _s ^* and d _t ^* are line current conduction ratios, and the phase angle φ is 0 ≦ φ ≦ π / 3)
Or by using a table set in advance based on the predetermined formula, and the absolute value of the line current conduction ratio d _s ^* and the line current conduction The absolute value of the ratio d _t ^* represents the slope region of the trapezoidal command signal corresponding to two of the three phases of the three-phase AC input voltage, and the line current conduction ratio d _s ^*. , d _t ^*, the absolute value of the line current conduction ratio _dr ^* represents the slope region of the trapezoidal wave-shaped command signal corresponding to the remaining phase ,
When the absolute value of the line current conduction ratio d _s ^* is 1, | d _r ^* | = 1− | d _t ^* |, and when the absolute value of the line current conduction ratio d _t ^* is 1. Is | d _r ^* | = 1− | d _s ^* |, and when neither the absolute value of the line current conduction ratio d _s ^* nor the absolute value of d _t ^* is equal to 1, | d _r ^* | = 1, A method for controlling a power converter.

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