KR20210108126A - Wgb based power converter and power converter control method including output filter controlling output voltage of matrix converter - Google Patents

Abstract

The present invention relates to a WGB-based power converting device, which comprises: an N-phase (N is an integer) matrix converter; and an output filter in which a filter inductor (L_f) having one end is connected in series with an output voltage terminal output from the matrix converter, and a filter capacitor (C_f) and a damping resistor are connected in series with a line branched from the other end of the filter inductor. The output filter includes: a filter inductance setting unit for setting a filter inductance to allow a voltage drop of an output terminal of the matrix converter by the filter inductor to be included in a range of 2 to 5% of a rated voltage; a resonance frequency setting unit for setting a resonance frequency in a range greater than a switching frequency of the matrix converter and less than 10 MHz; and a filter capacitance calculating unit for calculating a filter capacitance through the filter inductance and the resonance frequency. Accordingly, a standard specification can be easily satisfied, a voltage rise is relieved to reduce a leakage current, and the stability and reliability of the entire system can be improved.

Description

WGB-based power converter and power converter control method including an output filter that controls the output voltage of a matrix converter

The present invention relates to an apparatus and method for controlling a filter applied to an input terminal of a motor by controlling an output terminal voltage of a power converter between a motor having a plurality of phases and a power converter.

An electric motor is a device that converts electrical energy into mechanical energy. A drive is a device that controls the speed of a motor by receiving power supplied from a power source, converting direct current (DC) power into alternating current (AC) within the drive, and supplying it to the motor by varying the voltage and frequency.

However, in motor drive systems, the higher the switching speed, the higher the voltage (dv/dt), which in turn causes. It causes insulation breakdown and leakage current problems in the motor drive system. First, the insulation generated at the input terminal of the motor may be broken due to the voltage rise. Voltage reflection occurs in the cable due to the difference in cable impedance between the motor drive system and the motor and the impedance of the motor. Due to the voltage reflection wave, the voltage applied to the input terminal of the motor can be increased up to 2 times. If a voltage higher than the insulation capacity of the motor is applied, the insulation at the input terminal of the motor is broken, which causes a failure and reduces the life of the motor.

In the motor drive system, when the switching speed increases, leakage current flows through the parasitic capacitor and the ground wire. When a high dv/dt voltage is supplied to the motor from the motor drive system, leakage current flows through parasitic capacitance components such as stator-ground frame capacitance, stator-rotor capacitance, shaft-bearing capacitance, and shaft-stator magnet capacitance in the motor. can Leakage current causes mechanical defects in the components of the motor, and applies common mode noise to the sensing and control unit of the motor drive system, which may cause system malfunction.

In addition, in the motor drive system with the increased switching speed, the ripple of the motor current is severe due to the low switching frequency, which may result in additional loss of the motor. Sudden voltage fluctuations cause the cable to act as an antenna and cause electromagnetic interference (EMI). The EMI problem can be overcome by shielding the cable, but cost and loss are a problem.

On the other hand, a power semiconductor is a semiconductor device used in a power conversion device, and is a device having a control and conversion function for distributing power to a system. The improvement of the performance of the power semiconductor is directly related to the improvement of the performance of the electric system using it, that is, the power conversion device. The recently developed WBG (Wide Band Gap) device operates stably at high temperature, has high thermal conductivity, low resistance, and high withstand voltage compared to the existing silicon (Si) semiconductor device. Recent studies have been conducted in the direction of reducing the size of the system and increasing the overall system efficiency by configuring a power conversion system based on WBG.

In particular, if a WBG device is used in a system for a variable speed motor drive, it can have very low loss at a high switching frequency and can be driven even in a very high temperature environment. Due to the advantages of these WBG devices, WBG-based motor drive systems are being used in industrial fields such as electric vehicles, deep-sea pumps, aerospace, and railways. In addition, the WBG device is economical because the size and number of passive devices such as filters of power converters can be reduced because of its high switching speed.

However, the WBG-based motor drive system has a higher switching speed than before, so the problem of voltage rise (dv/dt) may intensify. Therefore, in IEC and NEMA, the output filter of the motor drive system is used to limit the peak value and rise time of the voltage applied to the input terminal of the motor to ensure the stable operation of the motor. A sine wave filter and a dv/dt filter are used for the output filter. The sine wave filter is designed to apply only the voltage component of the fundamental frequency to the motor input stage, and the dv/dt filter is designed to control the peak value and rise time of the motor drive system output voltage. Accordingly, the present applicant has conducted research and development on a power conversion device and a power conversion device control method including a dv/dt filter that can further improve the dv/dt filter and can flexibly select the number of filter enactments according to the desired specification. . Accordingly, it was confirmed that the performance was improved compared to the previously used dv/dt filter.

The present invention is a power conversion device and a method for controlling the power conversion device, between the output of a WBG-based motor drive system and the motor input terminal to reduce the dv/dt size generated at the motor input stage and secure the driving stability and reliability of the motor An object of the present invention is to provide an apparatus and method for controlling a filter provided in the .

The problems to be solved by the present invention are not limited to the aforementioned problems. Other objects and advantages of the present invention will be more clearly understood by the following description.

In order to achieve the above object, the present invention provides a WGB-based power converter, comprising: an N-phase (N is an integer) matrix converter; _{and a filter inductor (L f} ) having one end connected in series to an output voltage terminal output from the matrix converter, a _{filter capacitor (C f} ) and a damping resistor connected in series to a line branched from the other end of the filter inductor. wherein the output filter comprises: a filter inductance setting unit configured to set the filter inductance so that a voltage drop at the output terminal of the matrix converter by the filter inductor is included in a range of 2% or more and 5% or less of a rated voltage; a resonance frequency setting unit for setting a resonance frequency in a range greater than the switching frequency of the matrix converter and less than 10 MHz; and a filter capacitance calculator configured to calculate a filter capacitance based on the filter inductance and the resonance frequency to control the output voltage of the matrix converter.

Preferably, the apparatus may further include a rise time calculator configured to calculate a rise time of the output terminal voltage of the matrix converter through the filter inductance and the filter capacitance.

Preferably, the filter capacitance, the relationship between the filter inductance and the resonant frequency may be defined by the following [Equation 1], and may be calculated through the following [Equation 1].

[Equation 1]

where f _dvdt is the resonant frequency, L _f is the filter inductance, and C _f is the filter capacitance.

Preferably, the rise time, the relationship between the filter inductance and the filter capacitance may be defined by the following [Equation 2], and may be calculated through the following [Equation 2].

[Equation 2]

where Trise is the resonance frequency, L _f is the filter inductance, and C _f is the filter capacitance.

Preferably, when the rise time is less than 0.1 μs, a reset unit for adjusting the filter inductance or the resonance frequency may be further included.

Preferably, it may further include a power loss calculator that sets a value of the damping resistor and calculates a power loss generated by the damping resistor.

Preferably, the power loss caused by the damping resistor is

It can be calculated through the following [Equation 3].

[Equation 3]

However, P _d is the power loss, v ₀ ² is the input voltage value, C _f is the filter capacitance, and f _sw is the switching frequency of the matrix converter.

In addition, in order to achieve the above object, the present invention provides an N-phase (N is an integer) matrix converter; _{and a filter inductor (L f} ) having one end connected in series to an output voltage terminal output from the matrix converter, a _{filter capacitor (C f} ) and a damping resistor connected in series to a line branched from the other end of the filter inductor. A method of controlling a WGB-based power converter comprising: a step of setting a filter inductance such that a voltage drop of the matrix converter output stage by a filter inductor is included in a range of 2% or more and 5% or less of a rated voltage; b step of setting a resonance frequency in a range greater than the switching frequency of the matrix converter and less than 10 MHz; c step of calculating a filter capacitance based on the filter inductance and the resonance frequency; a d step of calculating a rise time of the output terminal voltage of the matrix converter through the filter inductance and the filter capacitance; e step of resetting the filter inductance or the resonance frequency when the calculated rise time is less than 0.1 μs; and an f step of calculating the power loss due to the damping resistor.

Preferably, it may be a computer program stored in a computer-readable recording medium to execute steps a to f.

According to the present invention, it is possible to reduce the dv/dt size to a level that satisfies the NEMA standard relatively simply without performing complex EMI analysis. As the dv/dt size decreases and the dv/dt performance improves, the leakage current flowing in the motor and the leakage current existing in the motor drive system are reduced, thereby reducing the frequency of system malfunction.

The dv/dt filter of the present invention can reduce the noise of the high-frequency component of the output wave of the electric motor drive. In particular, in a WBG-based motor drive system capable of high-frequency operation, several MHz of noise is generated due to high dv/dt. However, when the dv/dt filter of the present invention is applied, noise in the corresponding band can be reduced, so that the driving stability and reliability of the entire system can be improved. This shows a size reduction effect of about 10 times or more in the high-frequency band of about 3 MHz or more.

In the dv/dt filter of the present invention, it is possible to configure the filter even with a very low capacitance that does not need to consider the loss due to the filter capacitor. In addition, according to the present invention, there is an advantage that the core loss and copper loss due to the filter inductor are about 5 times less effective than the sinusoidal filter loss under the same switching frequency condition.

In addition, according to the present invention, since the resonant frequency is located in a relatively high frequency band, the output filter value can be selected to be low, so that the size of the filter can be reduced. Therefore, it has the advantage that an economical system configuration is possible.

1 shows a structural diagram of a power conversion system according to an embodiment of the present invention.
2 is a block diagram of an output filter according to an embodiment of the present invention.
3 shows an equivalent circuit of the output filter of the power conversion device according to an embodiment of the present invention.
4 is a Bode diagram graph of an output filter transfer function according to a damping resistance as an experimental example of the present invention.
5 shows an output voltage and an output current waveform according to the presence or absence of an output filter as an experimental example of the present invention.
6 is an enlarged graph of the output voltage waveform of FIGS. 5A and 5B as an experimental example of the present invention.
7 shows a leakage current waveform according to the presence or absence of an output filter as an experimental example of the present invention.
8 is a graph showing a frequency spectrum according to the presence or absence of an output filter as an experimental example of the present invention.
FIG. 9 shows a control method of a power conversion device in which an output filter controls an output voltage increase of an output terminal of an N-phase (N is an integer) matrix converter according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the contents described in the accompanying drawings. However, the present invention is not limited or limited by the exemplary embodiments. The same reference numerals provided in the respective drawings indicate members that perform substantially the same functions.

Objects and effects of the present invention can be naturally understood or made clearer by the following description, and the objects and effects of the present invention are not limited only by the following description. In addition, in describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

1 shows a structural diagram of a power conversion system 1 according to an embodiment of the present invention. The power conversion system 1 may include an AC power supply unit 10 , an input filter 30 , a power conversion device 50 , and a load 70 . The power conversion system 1 converts the power supplied from the AC power supply unit 10 to be suitable for the load 70 that is to be driven. The power conversion system 1 of FIG. 1 according to an embodiment of the present invention may be connected to three input phases (A phase, B phase, C phase) and output three phases (U phase, V phase, W phase).

The AC power supply unit 10 may be single-phase or three-phase, and finally supplies power to the load 70 . In FIG. 1, which is an embodiment of the present invention, three-phase (A-phase, B-phase, C-phase) AC power is shown.

The input filter 30 may be an LC filter or a CL filter, and each phase of the AC power supply unit 10 and one end of the inductor of the input filter 30 may be connected in series, and one end of the inductor of the input filter 30 may be connected in series. Alternatively, a capacitor of the input filter 30 may be connected to a line branched from the other end to configure the input filter 30 . A resistor may be connected in parallel to the inductor of the input filter 30 .

The power converter 50 may be manufactured based on a WBG device, and may include a matrix converter 510 having a plurality of phases and an output filter 530 . The power converter 50 may control the voltage increase of the output terminal of the matrix converter 510 through the output filter 530 to apply it to the input terminal of the load 70 .

According to an embodiment of the present invention, the matrix converter 510 may be a GaN FET-based direct matrix converter. In the direct matrix converter, the bidirectional switch is an AC/AC power conversion device and may suppress harmonic currents of the AC power supply unit 10 . The matrix converter 510 may be composed of a plurality of bidirectional switches connected to each phase of the AC power supply unit 10 , and each switch may be composed of a bidirectional switch in which two unidirectional switches are connected in series. Referring to FIG. 1 , the matrix converter 510 may consist of a total of nine bidirectional switches by connecting three bidirectional switches to each phase of the AC power supply unit 10 .

The output filter 530 may control the peak voltage and the rise time of the voltage with respect to the voltage of the output terminal of the matrix converter 510 . The output filter 530 may include an inductor and a capacitor, and a resistor may be connected to the inductor in parallel to prevent damping and overvoltage. The output filter 530 may be designed such that one end of the filter inductor is connected in series to the output voltage terminal output from the matrix converter 510, and a filter capacitor and a damping resistor are connected in series to a line branched from the other end of the filter inductor. .

The output voltage control standard of the matrix converter 510 according to an embodiment of the present invention is based on a standard of the National Electrical Manufacturers Association (NEMA). The limiting condition for driving the load 70 stipulated by NEMA is that, when the rated voltage of the input terminal of the load 70 is 600V or less, the peak voltage at the input terminal of the load 70 is 3.1 times or less of the rated voltage of the load 70. , it is stipulated that the rise time (10% to 90%) of the input terminal voltage of the load 70 is 0.1 μs or more.

Since the load 70 receives a signal whose voltage quality is secured by controlling the voltage rise from the output filter 530 , driving stability and reliability can be secured.

2 is a block diagram of an output filter 530 according to an embodiment of the present invention. The output filter 530 controls the voltage rise of the output terminal of the matrix converter 510 to alleviate the voltage rise problem that occurs more severely due to the fast switching characteristics of the WBG element-based power converter 50 .

The output filter 530 includes a filter inductance setting unit 5301 , a resonance frequency setting unit 5303 , a filter capacitance calculating unit 5305 , a rise time calculating unit 5307 , a power loss calculating unit 5308 , and a resetting unit 5309 . ) may be included.

The filter inductance setting unit 5301 may set the filter inductance so that the voltage drop at the output terminal of the matrix converter 510 by the filter inductor of the output filter 530 is included in the range of 2% or more and 5% or less of the rated voltage. The range of 2% or more and 5% or less of the rated voltage may mean 0.02pu ~ 0.05pu of the rated voltage.

표현할 수 있다.The resonance frequency setting unit 5303 may set the _{resonance frequency f dvdt} in a range greater than _{the switching frequency f sw} of the matrix converter 510 and less than 10 MHz. In other words

can express

The filter capacitance calculator 5305 may calculate the filter capacitance based on the filter inductance and the resonance frequency. The filter capacitance may be defined by the following [Equation 1] in relation to the filter inductance and the resonance frequency, and may be calculated through the following [Equation 1].

However, f _dvdt is the resonance frequency, L _f is the inductance _{of the output filter 530 , C f} is the capacitance of the output filter 530 .

The rise time calculator 5307 may calculate the rise time of the output terminal voltage of the matrix converter 510 based on the filter inductance and the filter capacitance. The rise time may be defined by the following [Equation 2] in relation to the filter inductance and the filter capacitance, and may be calculated through the following [Equation 2].

However, Trise is the resonance frequency, L _f is the inductance _{of the output filter 530 , C f} is the capacitance of the output filter 530 .

The power loss calculator 5308 may set the value of the damping resistor and calculate the power loss generated by the damping resistor. The power loss caused by the damping resistor can be calculated through the following [Equation 3].

However, P _d is the power loss, v ₀ ² is the input voltage value, C _f is the output filter 530 capacitance, f _sw is the switching frequency of the matrix converter (510).

The reset unit 5309 may adjust the filter inductance or the resonance frequency when the rise time calculated by the rise time calculator 5307 is less than 0.1 μs compared to 0.1 μs (a limiting condition of NEMA).

3 shows an equivalent circuit of the output filter 530 of the power conversion device 50 according to an embodiment of the present invention. The output filter 530 may include a filter inductor (L _f ), a filter capacitor (C _f ), and a damping resistor (R _d ). The transfer function between the matrix converter 510 and the load 70 may be composed of a secondary system function, and may be expressed as [Equation 4].

However, G(s) is a transfer function of the equivalent circuit of FIG. 3 , L _f is a filter inductor, C _f is a filter capacitor, and R _d is a damping resistor.

In addition, a damping ratio may be determined by the _{filter inductor L f} , the filter capacitor C _f , and the damping resistor R _{d .} Therefore, the user can flexibly select and use the filter enactment water according to the desired specification. However, according to an embodiment of the present invention, the _{settable range of the filter inductor (L f} ), the filter capacitor (C _f ), and the damping resistor (R _d ) should be a range that satisfies the NEMA limit condition. The filter inductor L _f , the filter capacitor C _f , and the damping resistor R _d may be set or calculated from the above-described configuration of the output filter 530 of FIG. 2 . In addition, the power conversion device 50 of FIG. 9 to be described later may be set or calculated through a control method. The relationship between the damping ratio and the filter inductor (L _f ), the filter capacitor (C _f ), and the damping resistor (R _d ) may be expressed as {Equation 5].

However, ξ is the damping ratio, R _d is the damping resistor, C _f is the filter capacitor, and L _f is the filter inductor.

4 is a Bode diagram graph of the transfer function of the output filter 530 according to the damping resistance as an experimental example of the present invention. In more detail, FIG. 4A shows the magnitude (dB) according to the frequency (x-axis) under different damping resistance value conditions of the output filter 530 , and FIG. 4B shows the phase (deg) according to the frequency (x-axis). At this time, the yellow line has a damping resistance of 10Ω, the red line has a damping resistance of 50Ω, and the blue line has a damping resistance of 100Ω.

The damping resistor may be connected in parallel with the filter inductor of the output filter 530 to prevent damping and overvoltage in the power conversion system 1 . In the absence of the damping resistor, since the gain value at the resonant frequency becomes infinite, the resonant frequency component appears predominantly in the output voltage, so it is difficult to expect the effect of controlling the voltage increase to be achieved by the output filter 530 of the present invention.

Referring to FIG. 4A , as the damping resistance increases, the gain value at the resonant frequency may be decreased. That is, when the damping resistance is 100 Ω (blue), the magnitude (dB) according to frequency is smaller than that of 10 Ω (yellow). However, if a damping resistor is added or the value of the damping resistor is increased, a loss may occur due to the damping resistor. In this case, the loss caused by the damping resistor can be predicted using the input voltage value, the filter capacitor, and the switching frequency as shown in [Equation 3].

5 shows the output voltage and output current waveforms according to the presence or absence of the output filter 530 as an experimental example of the present invention. In more detail, Figure 5a is an output waveform over time of the power converter 50 without an output filter 530, Figure 5b is an output waveform over time of the power converter 50 when there is an output filter 530 am. The output filter 530 of FIG. 5B may be a dv/dt filter. 5A and 5B, the waveform shown at the top of the figure is the output voltage waveform, and the waveform shown at the bottom of the figure is the output current waveform. In FIGS. 5A and 5B , V _UV is the input voltage of the load 70 , and I _U is the current of the load 70 in the U phase, which is one of the output three phases.

The switching frequency in FIG. 5A is 10 kHz, and in FIG. 5A without the output filter 530 , it can be confirmed through the waveforms of _{V UV} and I _{U that there is a higher frequency component than the switching frequency.} However, in the output current waveform of FIG. 5B with the output filter 530, the high frequency component was significantly reduced. Although it is observed that the output voltage waveform of FIG. 5B still has a high frequency component, it will be described in more detail that the high frequency component is also reduced in the output voltage waveform through FIG. 6 to be described later. Accordingly, it can be confirmed that the output filter 530 removes the high-frequency component of the matrix converter 510 .

6 is an enlarged graph of the output voltage waveform of FIGS. 5A and 5B as an experimental example of the present invention. As in FIG. 5 , FIGS. 6A and 6B are classified according to the presence or absence of the output filter 530 . 6A and 6B both show a waveform in which the output voltage waveform is constant and then suddenly increases, and after the voltage increases, a waveform in which the amplitude of the waveform decreases and then gradually converges to a certain range is shown. In determining whether to remove the high-frequency component, it can be seen that the high-frequency component is removed more significantly in FIG. 6B than in FIG. 6A. Also in terms of the rise time of the voltage, in FIG. 6A without the output filter 530, the rise time of the output voltage is 78 ns, which has a fast rise time. Due to this, the signal output from the matrix converter 510 has a high frequency component and a high voltage spike. On the other hand, the rise time in FIG. 6b with the output filter 530 is 489ns, which satisfies the 0.1us rise time, which is the NEMA standard limiting condition, and alleviates the high-frequency component.

7 shows a leakage current waveform according to the presence or absence of an output filter 530 as an experimental example of the present invention. In more detail, Figure 7a is a leakage current waveform of the power conversion device 50 over time when there is no output filter 530, and Figure 7b is a power conversion device 50 over time when there is an output filter 530 This is the leakage current waveform. The leakage current may cause a mechanical failure of the load 70 , and may cause a system malfunction by applying noise to the sensing and control unit of the power conversion device 50 , which is a problem. Accordingly, referring to FIGS. 7A and 7B , it can be seen that the magnitude of the leakage current is reduced in FIG. 7B with the output filter 530 .

8 is a graph showing a frequency spectrum according to the presence or absence of an output filter 530 as an experimental example of the present invention. In more detail, the blue graph is a frequency spectrum when the output filter 530 is not present, and the red graph is a frequency spectrum when the output filter 530 is present. As described above, in the WBG-based power conversion device 50 according to the embodiment of the present invention, noise is generated due to a high voltage rise, and there is a problem in that the driving stability and reliability of the power conversion system 1 are reduced. Therefore, in order to reduce noise, it is necessary to remove high-frequency components. Referring to FIG. 8 , although the two waveforms have similar sizes in the low frequency band, it can be confirmed that the red graph with the output filter 530 is reduced in size by about 10 times or more than the blue graph in about 3 MHz band or higher.

9 shows a method of controlling the power conversion device 50 including the output filter 530 in order to control the voltage rise occurring at the input terminal of the load 70 as another embodiment of the present invention. (a) step of setting the filter inductance, (b) step of setting the resonance frequency, (c) step of calculating the filter capacitance, (d) step of calculating the rise time, (e) step of resetting according to the rise time , it may include a step (f) of calculating the power loss. In addition, according to an embodiment of the present invention, steps (a) to (f) may be performed inside a computer as a computer program, and may be stored in a computer-readable recording medium.

Step (a) means setting the filter inductance so that the voltage drop at the output stage of the matrix converter by the filter inductor falls within the range of 2% or more and 5% or less of the rated voltage. Step (b) means setting the resonance frequency in a range greater than the switching frequency of the matrix converter and less than 10 MHz. Step (c) means calculating the filter capacitance through the filter inductance and the resonance frequency. Step (d) refers to calculating the rise time of the output terminal voltage of the matrix converter through the filter inductance and the filter capacitance. Step (e) means resetting the filter inductance or resonance frequency when the calculated rise time is less than 0.1 μs. Step (f) means calculating the power loss due to the damping resistor. Steps (a) to (f) show a process performed in an embodiment of the power conversion system 1 and the meaning and significance of each step has been described above, and redundant descriptions are omitted.

Although the present invention has been described in detail through representative embodiments above, those of ordinary skill in the art will understand that various modifications are possible within the limits without departing from the scope of the present invention with respect to the above-described embodiments. will be. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by all changes or modifications derived from the claims and equivalent concepts as well as the claims to be described later.

1: Power conversion system
10: AC power supply unit
30: input filter
50: power converter
510: matrix converter
530: output filter
5301: filter inductance setting unit
5303: resonant frequency setting unit
5305: filter capacitance calculator
5307: rise time calculator
5308: power loss calculator
5309: reset unit
70: load

Claims (9)

In the WGB-based power conversion device,
N-phase (N is an integer) matrix converter; and
_{A filter inductor (L f} ) having one end connected in series to an output voltage terminal output from the matrix converter, a _{filter capacitor (C f} ) and an output filter having a damping resistor connected in series to a line branched from the other end of the filter inductor including,
The output filter is
a filter inductance setting unit for setting a filter inductance such that a voltage drop of the matrix converter output terminal by the filter inductor is included in a range of 2% or more and 5% or less of a rated voltage;
a resonance frequency setting unit for setting a resonance frequency in a range greater than the switching frequency of the matrix converter and less than 10 MHz; and
A power converter comprising a filter capacitance calculator for calculating a filter capacitance through the filter inductance and the resonance frequency to control the output voltage of the matrix converter.

The method of claim 1,
Power conversion device, characterized in that it further comprises a rise time calculator for calculating a rise time of the output terminal voltage of the matrix converter through the filter inductance and the filter capacitance.

The method of claim 1,
The filter capacitance is
The relationship between the filter inductance and the resonance frequency may be defined by the following [Equation 1], and the power conversion device, characterized in that it is calculated through the following [Equation 1].
[Equation 1]

where f _dvdt is the resonant frequency, L _f is the filter inductance, and C _f is the filter capacitance.

3. The method of claim 2,
The rise time is
The relationship between the filter inductance and the filter capacitance may be defined by the following [Equation 2], and the power conversion device, characterized in that it is calculated through the following [Equation 2].
[Equation 2]

where Trise is the resonance frequency, L _f is the filter inductance, and C _f is the filter capacitance.
3. The method of claim 2,
When the rise time is less than 0.1 μs, the power conversion device further comprising a reset unit for adjusting the filter inductance or the resonance frequency.
The method of claim 1,
Setting the value of the damping resistor, the power conversion device characterized in that it further comprises a power loss calculator for calculating the power loss generated by the damping resistor.
7. The method of claim 6,
The power loss caused by the damping resistor is,
Power conversion device, characterized in that calculated through the following [Equation 3].
[Equation 3]

However, P _d is the power loss, v ₀ ² is the input voltage value, C _f is the filter capacitance, and f _sw is the switching frequency of the matrix converter.

N-phase (N is an integer) matrix converter; and
_{A filter inductor (L f} ) having one end connected in series to an output voltage terminal output from the matrix converter, a _{filter capacitor (C f} ) and an output filter having a damping resistor connected in series to a line branched from the other end of the filter inductor In the method of controlling a WGB-based power conversion device comprising:
a step of setting the filter inductance so that the voltage drop of the output terminal of the matrix converter by the filter inductor is included in the range of 2% or more and 5% or less of the rated voltage;
b step of setting a resonance frequency in a range greater than the switching frequency of the matrix converter and less than 10 MHz;
c step of calculating a filter capacitance based on the filter inductance and the resonance frequency;
a d step of calculating a rise time of a voltage at an output terminal of the matrix converter through the filter inductance and the filter capacitance;
e step of resetting the filter inductance or the resonance frequency when the calculated rise time is less than 0.1 μs; and
Power conversion device control method comprising the step f of calculating the power loss due to the damping resistor.
9. The method of claim 8,
A computer program stored in a computer-readable recording medium to execute steps a to f.

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