JP2003289669A - Power supply unit for constant-power output - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply unit suitable for constant-power control, and a method to control the unit. <P>SOLUTION: During an output current is smaller, a phase of a voltage induced to first to fourth secondary coils 23<SB>1</SB>to 23<SB>4</SB>is arranged to be controlled, and the first and the third coils 23<SB>1</SB>to 23<SB>4</SB>are arranged to be equivalently 4-in series connection. When the output current becomes larger, the phase is controlled, and a period of the 4-in series connection is added by a period of 2-in series/2-in parallel connections, and an output voltage is decreased in the ratio of the period. When the output current becomes larger than when the period of the 4-in series connection becomes zero, the period of the 2-in series/2- in parallel connections is added by a period of 4-in parallel connection, and the ratio is controlled to reduce the output voltage. If power is controlled to be constant when the output voltage is decreased, constant-power control is performed by the phase control. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the technical field of power supply devices, and more particularly to the technical field of power supply devices suitable for constant power output.

[0002]

2. Description of the Related Art In certain devices such as a film forming device, a power supply device capable of constant power output is required.

Reference numeral 102 in FIG. 15 is an example of the power supply device, which has a primary side sub-conversion unit 107, a transformer T, a secondary side rectifier circuit 124, and a smoothing circuit 127.

The transformer T comprises a primary winding W ₁ and a secondary winding W ₂
The sub-converter 107 has four transistors Q _{1 to} Q ₄ . 4 transistors Q _{1 to} Q ₄
And the primary winding W ₁ constitute an H bridge circuit,
The DC voltage output from the DC voltage source 110 is applied to the H-bridge circuit.

The H-bridge circuit is composed of two transistors (Q ₁ , Q ₂ ) and (Q ₃ , Q ₂ ) connected via a primary winding W _1.
4 ) becomes one set, and when the transistors Q ₁ and Q _{2 of} one set become conductive, and the transistors (Q ₃ and Q ₄ ) of the other set
The current flows in the opposite direction to the primary winding W ₁ when the current is conducted. That is, alternating current flows through the primary winding W ₁ by alternately conducting one set and the other set.

[0006] are magnetically coupled to the primary winding W ₁ and the secondary winding W _2, when an alternating current flows through the primary winding W _1, an alternating voltage is induced in the secondary winding W _2.

The rectifier circuit 124 is a bridge-connected four
It is composed of individual diodes D _{1 to} D ₄ . The AC voltage induced in the secondary winding W ₂ is full-wave rectified by the rectifier circuit 124 and output to the smoothing circuit 127. here,
While the first set of transistors (Q ₁ , Q ₂ ) are conducting,
While one set of diodes (D ₁ , D ₂ ) is forward biased and the second set of transistors (Q ₃ , Q ₄ ) is conducting, another set of diodes (D ₃ , D ₄ ) is It is forward biased and a current is supplied to the smoothing circuit 127.

The smoothing circuit 127 includes the inductance element 1
25 and a capacitor 126, the rectifier circuit 12
The current supplied from 4 is smoothed and output between the output terminal 38 and the ground terminal 39.

Reference numeral 128 is a load, which is connected between the output terminal 38 and the ground terminal 39, and is supplied with a DC output voltage V ₀ and an output current I ₀ from the power supply device 102.

When the constant power control is performed, there are problems that the utilization efficiency of the transformer is deteriorated and that the efficiency is lowered due to the increase of the primary side effective value current.

Further, the output voltage V supplied to the load 128
_{Since the} transformer is designed by the product of _{0 and} the maximum value of the output current I ₀ , there is a problem that the utilization efficiency of the primary winding W ₁ and the secondary winding W ₂ is low when constant power control is performed.

[0012]

SUMMARY OF THE INVENTION The present invention was created in order to solve the disadvantages of the prior art described above, and its object is to provide a power supply device suitable for constant power control and a control for controlling the power supply device. To provide a method.

[0013]

In order to solve the above-mentioned problems, the invention according to claim 1 is such that an AC current is supplied from a main conversion unit for generating an AC current from a DC voltage source and an AC current is supplied from the main conversion unit. First to fourth primary windings, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, and the first to fourth secondary windings A power supply circuit having a rectifier circuit that rectifies an AC voltage induced in a line and outputs the rectified voltage to a cathode connection point and an anode connection point, and a smoothing circuit that smoothes the voltage output to the cathode connection point and the anode connection point. The rectifier circuit has first to fifth rectifier element series circuits in which rectifier elements are connected in series at first to fifth connection points, respectively, and the first to fourth secondary windings are provided. Are connected in series in this order, and the first to fourth secondary windings are connected in series in the circuit. The ends and the portions where the first to fourth secondary windings are connected to each other are respectively connected to the first to fifth connection points, and are connected to the cathode side of the first to fifth rectifying element series circuits. And the anode side are connected to each other at a cathode connection point and an anode connection point, respectively, and a voltage generated at the cathode connection point and the anode connection point is smoothed by the smoothing circuit and supplied to a load. Is. According to a second aspect of the present invention, the main conversion unit is the first
~ The phase of the AC voltage induced in the fourth secondary winding is controlled, and the voltage induced in the first to fourth secondary windings is added to the cathode during the operation period of the power supply circuit. The power supply circuit according to claim 1, wherein the power supply circuit is configured to include four series connection periods applied between a connection point and the anode connection point. According to a third aspect of the present invention, the main conversion unit controls the phase of the AC voltage induced in the first to fourth secondary windings, and the first to the first during the operation period of the power supply circuit. 4. The voltage induced in four secondary windings is configured to include four parallel connection periods applied in parallel between the cathode connection point and the anode connection point. It is the power supply circuit according to any one of claims. In the invention according to claim 4, the main converter controls the phase of the AC voltage induced in the first to fourth secondary windings, and during the operation period of the power supply circuit, the first to first So that the voltages of two windings of the four secondary windings are added, and the added voltage includes two series and two parallel connection periods in which the voltages are applied in parallel to the cathode connection point and the anode connection point. The power supply circuit according to any one of claims 1 to 3, which is configured as described above. The invention according to claim 5 is the first to fourth parts to which alternating currents are respectively supplied.
Primary windings, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, respectively, and the first to fourth
Rectifying the AC voltage induced in the secondary winding of the, and having a rectifier circuit for outputting to the cathode connection point and the anode connection point, and smoothing the voltage output to the cathode connection point and the anode connection point A control method for controlling an output voltage of a power supply device supplied to a load, wherein the voltages induced in the first to fourth secondary windings are added and output to the cathode connection point and the anode connection point. 4 series connection periods and 2 series 2 in which a voltage obtained by adding two of the voltages induced in the first to fourth secondary windings is applied in parallel to the cathode connection point and the anode connection point. A parallel period is provided during the operation period of the power supply device, and the ratio of the 4 series connection period and the 2 series 2 parallel connection period is changed to control the magnitude of the output voltage. The invention according to claim 6 is
First to fourth primary windings to which alternating currents are respectively supplied, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, and the first to fourth windings A rectifying circuit that rectifies the AC voltage induced in the fourth secondary winding and outputs the rectified AC voltage to the cathode connection point and the anode connection point, and smoothes the voltage output to the cathode connection point and the anode connection point. A control method for controlling an output voltage of a power supply device that is supplied to a load by adding two of the voltages induced in the first to fourth secondary windings in parallel to each other. Two series and two parallel periods applied to the cathode connection point and the anode connection point, and voltages induced in the first to fourth secondary windings are applied in parallel between the cathode connection point and the anode connection point. 4 parallel connection periods are provided during the operation period of the power supply device, and the 2 series 2 Changing the ratio of the column connection period and 4 parallel connection period, a control method of the power supply for controlling the magnitude of the output voltage. According to a seventh aspect of the present invention, first to Nth primary windings to which alternating currents are respectively supplied and the first to Nth primary windings are provided.
First to Nth secondary windings, which are magnetically coupled to the Nth primary winding, and an AC voltage induced in the first to Nth secondary windings are rectified to form a cathode connection point and an anode. A control method for controlling an output voltage of a power supply device which has a rectifying circuit for outputting to a connection point, smoothes the voltage output to the cathode connection point and the anode connection point, and supplies the load to a load. N series connection operation in which the voltages induced in the first to Nth secondary windings are added and output to the cathode connection point and the anode connection point according to the magnitude of
It is a method of controlling a power supply device that switches a voltage induced in an Nth secondary winding in parallel between N parallel operation of outputting the voltage to the cathode connection point and the anode connection point. N is an integer of 4 or more. According to an eighth aspect of the present invention, during the transition from the N series connection operation to the N parallel connection operation, a series parallel connection operation in which two or more secondary windings are connected in parallel according to the magnitude of the output current is performed. The operating method of the power supply device according to claim 7, which is provided.

The present invention is configured as described above, and the terminals of two secondary windings are connected to the second to fourth connection points, and the first to fourth secondary windings are connected. By controlling the polarity of the voltage induced in the line, two or more secondary windings of the four secondary windings can be connected in series.

Further, since the rectifier circuit can individually rectify the voltages induced in the first to fourth secondary windings, two or more secondary windings of the four secondary windings are provided. The wires can be connected in parallel.

Therefore, when the output voltage is large and the output current is small, the first to fourth secondary windings are connected in series, and when the output current is large, the phase of the voltage induced in each secondary winding is increased. The output voltage can be reduced while increasing the output current by increasing the length of the parallel connection period included in the operation period of the power supply device and the number of secondary windings connected in parallel by controlling the power supply device.

If the output voltage is lowered while maintaining the product of the output current and the output voltage at a constant value, constant power control is performed.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Reference numeral 2 in FIG. 1 indicates a power supply device as an example of the present invention. The power supply device 2 includes a main conversion unit 7
And the first to fourth transformers 8 ₁ to 8 ₄ and the rectifier circuit 24.
And a smoothing circuit 27.

In the _first to _fourth transformers 8 ₁ to 8 ₄ , _first to _fourth primary windings 13 _{1 to} 13 ₄ and the first to fourth primary windings 13 _{1 to} 13 _{4 are provided.} And _1st to _4th secondary windings 23 ₁ to 23 ₄ which are magnetically coupled with each other.

The first to fourth primary windings 13 _{1 to} 13 _{4 have} the same number of turns and the first to fourth secondary windings 23 ₁ to 23 ₁ to
The numbers of turns of 23 ₄ are also equal to each other, the number of turns of the first to fourth primary windings 13 _{1 to} 13 ₄ is n ₁ , and the number of turns of the _first to _fourth secondary windings 23 ₁ to 23 ₄ is n. ₂ , the winding ratios n ₂ / n ₁ = N of the _first to _fourth transformers 8 ₁ to 8 ₄ are equal to each other.

Inside the main converter 7, first to fourth sub converters 7 _{1 to} 7 ₄ are provided. Each of the sub-conversion units 7 _{1 to} 7 ₄ is connected to the DC voltage source 10, and the DC voltage V _in output from the DC voltage source 10 is applied. Each sub conversion unit 7 _{1 to} 7 ₄
Generates an alternating current from the direct current voltage V _in and supplies it to the first to fourth primary windings 13 _{1 to} 13 ₄ , respectively. 1st to 4th
The sub-converters 7 _{1 to} 7 ₄ of the power supply circuit 102 of FIG.
Similarly to the sub conversion unit 107, the four transistors are provided, and the first to fourth primary windings 13 _{1 to} 13 ₄ and H
By forming the bridge circuit, an alternating current can be passed through the first to fourth primary windings 13 _{1 to} 13 ₄ .

When an alternating current flows through the first to fourth primary windings 13 _{1 to} 13 ₄ by the first to _fourth sub-converting sections 7 _{1 to} 7 ₄ , the first to fourth secondary windings An alternating voltage is induced in 23 ₁ to 23 ₄ .

The _first to _fourth secondary windings 23 ₁ to 23 ₄ are connected in series in this order. That is, the first secondary winding 2
_One end of 3 ₁ is connected to one end of the second secondary winding 23 ₂ ,
The other end of the secondary winding 23 ₂ of the second is connected to the third secondary winding 23 ₃ one end, the secondary winding 23 ₃ at the other end of the third and the fourth
Connected to one end of the secondary winding 23 ₄ of the
Except for the secondary winding 23 _1, 23 ₄ of the other end, the first to fourth secondary winding 23 _{1-23 4} are connected to each other.

[0024] The rectifier circuit 24 has a rectifying element series circuit 31 ₁ to 31 ₅ of the first to fifth. This 1st-5th
Rectifying element series circuit 31 ₁ to 31 _5, the rectifying element such as a PN junction diode or Schottky junction diodes 51a~
55a and 51b to 55b are connected in series.

Reference numeral a _{1 in} FIG. 1 indicates a first connection point where the rectifying elements 51a and 51b in the _first rectifying element series circuit 31 ₁ are connected to each other in series, and similarly, reference numeral a ₂ to.
a ₅ illustrates the second to fifth connection point. This second
The fifth connection point is that a _{2 to} a ₅ are the rectifying elements 52a to 55a, 52 in the _{second to fifth} rectifying element series circuits 31 _{2 to} 315.
b to 55b are portions connected in series with each other.

Of the two ends of the _first secondary winding 23 ₁ , the second
The other terminal not connected to the secondary winding 23 ₂ is connected to the first connection point a ₁ . The portion where the first secondary winding 23 ₁ and the second secondary winding 23 ₂ are connected is connected to the second connection point a ₂ , and similarly, the second secondary winding 23 2 _{The portion where 2} and the second secondary winding 23 ₃ are connected, and the portion where the third secondary winding 23 ₃ and the fourth secondary winding 23 ₄ are connected are respectively the third, Of the terminals of the _fourth secondary winding 23 ₄ , which is connected to the fourth connection points a ₃ and a ₄ and which is not connected to the _third secondary winding 23 ₃ , the terminal which is the fifth is Is connected to the connection point a ₅ .

First to fifth rectifying element series circuits 31 _{1 to} 3
The cathode side terminals of ₁₅ are all connected to the cathode connection point 36, and the anode side terminals are all connected to the anode connection point 37. Therefore, when an AC voltage is induced in the _first to _fourth secondary windings 23 ₁ to 23 ₄ , the AC voltage is rectified by the _first to fifth rectifying element series circuits 31 _{1 to} 31 ₅ , A positive voltage is applied to the cathode side connection point 36, and a negative voltage is applied to the anode side connection point 37.

The cathode side connection point 36 is connected to the output terminal 38 via the inductance element 25. The anode side connection point 37 is connected to the ground terminal 39.

The capacitor 26 is connected between the output terminal 38 and the ground terminal 39, and the load 28 is connected in parallel with the capacitor 26 between the output terminal 38 and the ground terminal 39. ing.

The capacitor 26 and the inductance element 25 constitute a smoothing circuit 27, and the rectifying circuit 24
The voltage rectified by is smoothed by the smoothing circuit 27 and supplied to the load 28.

The power supply circuit 2 has a control circuit 9, which controls the output voltage V ₀ (that is, between the output terminal 38 and the ground terminal 39) to be output from the output terminal 38 to the load 28. Voltage) and the output current I ₀ supplied to the load 28, the phase of the AC voltage generated in the _first to _fourth secondary windings 23 ₁ to 23 ₄ is changed, and as shown in the graph of FIG. Then, the output voltage V ₀ and the output current I ₀ are controlled. Although the control circuit 9 directly detects the voltage of the output terminal 38, the ground terminal 39 is provided with a current sensor 46 to detect the output current I ₀ as a current flowing through the ground terminal 39.

The first to fourth sub-converters 7 _{1 to} 7 ₄ have
The first and second secondary windings 23 are controlled by controlling the conduction period and the phase of the alternating current flowing through the _fourth primary windings 13 _{1 to} 13 _4.
The frequency of the AC voltage induced in _{1-23 4} controls the generation period of the phase, and positive and negative voltages.

The frequencies of the AC voltages induced in the _first to _fourth secondary windings 23 ₁ to 23 ₄ by the main converter 7 are equal,
Moreover, of the AC voltage, the positive voltage period and the negative voltage period are controlled to be equal.

When the ratio of the period in which the positive voltage is induced and the period in which the negative voltage is induced is the duty, the first to fourth
The duty of each of the secondary windings 23 ₁ to 23 ₄ is “1”.

The operation of the power supply circuit 2 will be described by taking the case where the output current I ₀ increases as an example. The first specified current value I ₁ is set in advance, and the power supply device 2 outputs the first output current I ₀ at the first. While the current is smaller than the specified current value I _{1 of the} above, the phases of the _first to _fourth secondary windings 23 ₁ to 23 ₄ are made equal to each other, and each secondary winding 2
A voltage of the same polarity is induced in 3 ₂ to 23 ₄ to connect points a _{2 to} a ₄
The voltage of the same polarity is applied to.

For example, when a positive voltage is induced in the _first secondary winding 23 ₁ and a positive voltage is applied to the first connection point a ₁ , the second to fourth secondary windings A positive voltage is also induced in 23 ₂ to 23 ₄ , and a positive voltage is applied to the _{second to fourth} connection points a _{2 to} a ₄ . On the contrary, when a negative voltage is induced in the _first secondary winding 23 ₁ and a negative voltage is applied to the first connection point a ₁ , the second to fourth secondary windings 23 ₂ The negative voltage is also induced in ~ 23 ₄ and the second to second connection points a _{2 to} a ₄
Is also applied with a negative voltage.

At this time, the first to fourth secondary windings 23 ₁ to
23 ₄ schematic waveform of the induced voltage V23 ₁ ~V23 ₄ shown in FIG. In FIG. 8 and FIGS. 9 to 12 to be described later, in the first secondary winding 23 ₁ , the first secondary winding 2
3 _{If 1} of the first voltage of positive polarity to the connection point a _1-side terminal is induced by a positive voltage, likewise, the second to fourth secondary winding 23 _{2-23 4,} respectively connected The case where a positive voltage is induced at the terminals on the points a _{2 to} a ₄ side is defined as a positive voltage.

[0038] Since the first through fourth secondary winding 23 _{1-23 4} induced voltage V23 ₁ ～V23 ₄ phases are matched, the first
A positive voltage is simultaneously induced in the fourth secondary windings 23 ₁ to 23 ₄ at time t ₁₁ , the induced voltage becomes zero at time t ₁₂ , and then all at once at time t ₁₃ . A negative voltage is induced at.

Reference numeral 4S in FIG. 8 indicates a period (4 series connection period) in which voltages of the same polarity are induced in all of the _first to _fourth secondary windings 23 ₁ to 23 ₄ .

Then, when the polarities of the voltages induced in the respective secondary windings 23 ₁ to 23 ₄ are inverted, that is, during the period 4S, the H-bridge circuit of the sub converters 7 _{1 to} 7 ₄ is constructed. All the transistors in the H-bridge are temporarily cut off so that a through current does not flow in the transistors, and the first to fourth secondary windings 2
The voltage induced in 3 ₁ to 23 ₄ becomes zero V. The period is indicated by the symbol D, and no current flows in the secondary winding during the period D.

However, during the period D, each secondary winding 23 ₁ ...
23 because it is very short period when compared to a single period T of the alternating voltage induced in _4, the power supply device 2 on the operation, can be ignored.

When the voltages at the _first to fifth connection points a _{1 to} a ₅ are represented by symbols E _{1 to} E ₅ , the _first to _fourth secondary windings 23 ₁ to 23 _{4 are shown.}
When a positive voltage is induced at the connection points and a positive voltage is applied to the connection points a _{1 to} a ₄ , the voltages E _{1 to} E ₅ are E ₅ <E ₄ <E ₃ <E ₂ <
Becomes a relationship of E _1, as a result, the rectifying element 51a~55a in the rectifier circuit 24, among the 51B～55b, and rectifying elements 51a to the first connection point a ₁ as the highest voltage and the anode terminal, and the lowest voltage Only the rectifying element 55b whose cathode terminal is the _fifth connection point a ₅ is forward-biased.
A current flows as shown by the broken line.

In this state, the first to fourth secondary windings 23
_{1-23 4} is in a state where the first secondary winding 23 ₁ first to fourth as the highest voltage of the secondary winding 23 _{1-23 4} are connected in series.

On the contrary, the first to fourth secondary windings 23₁~ 23_Four
When a negative voltage is induced in ₁<E₂<E₃<E_Four<
E_Five And the first connection point a₁Voltage E₁Is the lowest voltage, first
Connection point 5_FiveVoltage E_FiveIs the highest voltage, the first
Connection point a₁A rectifying element 51b whose cathode terminal is
Connection point 5_FiveIs a rectifying element 55a whose anode terminal is
The injury is forward biased and current flows as shown by the broken line in Fig. 3.
Be done. In this state, the fourth secondary winding 23_FourThe highest voltage
As the first to fourth secondary windings 23₁~ 23_FourConnected in series
Has been done.

As described above, the winding ratios N of the transformers 8 ₁ to 8 ₄ are equal to each other, and the primary windings 13 ₁ to ₁ 1
3 _4, because the same DC voltage V _in is applied, a voltage drop or due to the operation of the first to fourth sub-converter 7 _{1-7 4,}
Assuming that there is no loss in each of the transformers 8 ₁ to 8 _{4 and the} transformer is in an ideal state, the voltage induced in each of the secondary windings 23 ₁ to 23 ₄ has a magnitude of ± N · V _in .

Therefore, assuming that there is no voltage drop or wiring loss due to the operation of the rectifier circuit 24 and the secondary side circuit is in an ideal state, the _first to _fourth secondary windings 23 ₁ to 23 ₄ Is connected in series, a voltage of 4N · V _in is generated _in the rectifier circuit 24, smoothed by the smoothing circuit 27, and supplied to the load 28.

Therefore, the output current I ₀ is smaller than the first specified current value I ₁ , and the _first to _fourth secondary windings 23 ₁ to 23 ₄
Are connected in series, in the ideal state, the output current I ₀
Output voltage V of 4N · V _in regardless of the size of
₀ is maintained. That is, the first to fourth secondary windings 23 ₁ to 2
While 3 ₄ is connected in series, the power supply device 2 is operated in the constant voltage mode.

FIG. 13 is a graph showing the relationship between the output voltage V ₀ and the output current I ₀ of the power supply device 2. The operation from the operating point indicated by the symbol A to the operating point indicated by the symbol B is a constant voltage. Mode. The voltage V ₁ indicates a voltage of 4N · V _in .

When the output current I ₀ exceeds the first specified current value I ₁ , the phases of the _first and second secondary windings 23 ₁ and 23 ₂ are different from those of the third and fourth secondary windings. The phases of 23 ₃ and 23 ₄ start to shift. FIG. 9 is a graph showing a state in which the phase is shifted by ΔT _1. As a result of the phase shift, the first to fourth secondary windings 23
_A period in which the polarities of the voltages induced in ₁ to 23 ₄ are all equal,
There is a period in which the polarities of the voltages induced in the first and second secondary windings 23 ₁ and 23 ₂ and the voltages induced in the third and fourth secondary windings 23 are opposite to each other. .

Reference numeral 4S in FIG. 9 indicates a period in which the polarities of the voltages induced in the _first to _fourth secondary windings 23 ₁ to 23 ₄ are all equal, and during the period 4S, the first ~ The fourth secondary windings 23 ₁ to 23 ₄ become a 4-series connection circuit, and the rectifier circuit 2
A voltage of 4 to 4 N · V _in is output.

Reference numeral 2S2P is the first and second secondary windings 2
This is a period (2 series 2 parallel connection period) in which the polarities of the voltages induced in 3 ₁ and 23 ₂ are different from the polarities of the voltages induced in the _third and _fourth secondary windings 23 ₃ and 23 ₄ .

The first to fifth connection points a during the period 2S2P
₁ voltage E ₁ to E ₅ in ~a _5, the first, second secondary winding 2
When a positive voltage is induced in 3 ₁ , 23 ₂ and a negative voltage is induced in the third and fourth secondary windings 23 ₃ , 23 ₄ , E ₃ <E ₂ <E ₁ and Since E ₃ <E ₄ <E ₅ , and the turns ratios are equal, E ₂ = E ₄ and E ₁ = E ₅ ,
Rectifying element 51a whose anode terminal is connected to the connection point a _1, a ₅ highest voltage, and 55a, rectifying element 53b having a cathode terminal connected to the connection point a ₃ lowest voltage is forward biased, the dotted line in FIG. 4 Current flows as shown in. In this state, the _first to _fourth secondary windings 23 ₁ to 23 ₄ are connected to the first and second secondary windings 23 ₁ to 23 ₄ .
Secondary windings 23 ₁ and 23 _{2 form} one 2 series circuit, and the third and fourth secondary windings 23 ₃ and 23 _{4 form} another 2 series circuit, and the two series circuits are connected in parallel. Has been done.

On the contrary, the first and second secondary windings 23₁, 23₂
A negative voltage is induced in the third and fourth secondary windings 23
₃, 23_FourIf a positive voltage is induced in₂=
E_Four, And E₁= E_FiveIs a positive voltage is induced
Same as when₁<E₂<E₃ , E_Five<E_Four<E
₃ Is. In this state, the anode terminal
Continuation point a₃Rectifier element 53a connected to the cathode terminal
Is the connection point a with the lowest voltage₁, A _FiveRectifying element 51 connected to
b and 55b are forward biased, as shown by the dotted line in FIG.
An electric current flows. In this case also, the same two series circuits are connected in parallel.
You are connected.

During the period 2S2P, two parallel circuits are connected in parallel, so the voltage output from the rectifier circuit 24 is 2N · V _in , which is half that in the period 4S.

Therefore, the period 2S2P occupied in one cycle T
The output voltage V ₀ decreases as the ratio of V increases.

In the power supply device 2, the control circuit 9 measures the magnitude of the output current I ₀ by the current sensor 46, and the length of the period 2S2P with respect to the period 4S in one cycle,
That is, the ratio of the period 2S2P to the period 4S increases according to the amount by which the output current I ₀ exceeds the first specified current value I ₁ .

Particularly, in the power supply device 2, the output current I ₀
The ratio of 2S2P increases in proportion to the increase amount of the output voltage V0 and the _{value of} output voltage V ₀ × output current I ₀ is equal to the value at operating point B. Therefore, in this state, the power supply device 2 is operated in the constant power mode.

The period D in which the voltage induced in the _first to _fourth secondary windings 23 ₁ to 23 ₄ is zero is a very short period as compared with 1 cycle T and can be ignored.

When the output current I ₀ increases and the 4-series connection period 4S becomes zero as shown in FIG. 10, the entire period of one cycle T is occupied by the period 2S2P. In this state, the output voltage V ₀ is half the magnitude in the constant voltage mode, and in the constant power mode, the output current I ₀ is twice the magnitude of the _first specified current value I ₁ .

[0060] code C of Figure 13 shows the operating point is _{V 2 = V 1/2,} I 2 = I 1 × 2. In FIG. 13, the area between the operating point B and the operating point C is the constant power mode.

As can be seen from FIG. 10, in the state where one cycle T is occupied by the period 2S2P, the third and third voltages are induced with respect to the voltages induced in the _first and second secondary windings 23 ₁ and 23 ₂ . The voltages induced in the secondary windings 23 ₃ and 23 ₄ of No. ₄ have opposite phases, and the phase difference is 180 °.

From the state in which one cycle T is occupied by the period 2S2P, the output current I ₀ further increases and the first specified current value I ₁
Second time, the second and third secondary windings 23
_With respect to the phases of ₂ and 23 ₃ , the first and fourth secondary windings 23 ₁ and
23 _{4 is out} of phase. Reference numeral ΔT _{2 in} FIG. 11 indicates the amount of phase shift at this time.

When the phases of the _first and _fourth secondary windings 23 ₁ and 23 ₄ deviate from the phases of the second and third secondary windings 23 ₂ and 23 ₃ , the second and third secondary windings 23 ₁ and 23 ₄ are displaced from each other. While the polarities of the voltages induced in the secondary windings 23 ₂ and 23 ₃ are opposite to each other, the polarity of the induced voltage in the _first secondary winding 23 ₁ is the second secondary winding 23 ₂
Of the induced voltage of the second secondary winding 23
Polarity of ₄ of the induced voltage, polarity and different periods of the third secondary winding 23 ₃ of the induced voltage is generated.

Reference numeral 4P indicates the period (four parallel connection periods), and during the period 4P, the first and third secondary windings 2 are provided.
The induced voltages of 3 ₁ and 23 ₃ have the same polarity, and the induced voltages of the second and fourth secondary windings 23 ₂ and 23 ₄ have opposite polarities.

In the period 4P, a positive voltage is induced in the first and third secondary windings 23 ₁ and 23 _3, and a negative voltage is induced in the second and fourth secondary windings 23 ₂ and 23 ₄ . When a voltage is induced, the voltages E _{1 to} E _{5 at the first to fifth} connection points a _{1 to} a ₅ are E
₁ > E ₂ , E ₂ <E ₃ , E ₃ > E ₄ , E ₄ <E ₅ . Furthermore,
Since the turns ratios of the transformers 8 ₁ to 8 ₄ are equal, E ₂ =
E ₄ , and E ₁ = E ₃ = E ₅ .

As a result, the rectifying element 5 having the anode terminals connected to the connection points a ₁ , a ₃ and a ₅ to which the positive voltage is applied.
1a, 53a, 55a and a connection point a to which a negative voltage is applied
₂ , rectifying elements 52b, 5 having cathode terminals connected to a ₄
4b is forward biased and a current flows as shown by the dotted line in FIG. In this state, the first to fourth secondary windings 23 ₁ to
All of 23 ₄ are connected in parallel.

On the contrary, the first and third secondary windings 23
_{When a} negative voltage is induced in ₁ and 23 ₃ and a positive voltage is induced in the second and fourth secondary windings 23 ₂ and 23 ₄ ,
E ₁ <E ₂ , E ₂ > E ₃ , E ₃ <E ₄ , E ₄ > E ₅ , E ₂ = E ₄ ,
Further, E ₁ = E ₃ = E ₅ , and a rectifying element 52a having an anode terminal connected to the connection points a ₂ and a ₄ to which a positive voltage is applied,
54a and the rectifying elements 51b, 53b, 5 whose cathode terminals are connected to the connection points a ₁ , a ₃ , a ₅ to which a negative voltage is applied.
5b is forward biased and a current flows as shown by the dotted line in FIG. Even in this state, the first to fourth secondary windings 23 ₁ to
All of 23 ₄ are connected in parallel.

Assuming that a current value I ₂ which is twice the _first specified current value I ₁ is the second specified current value, the period 2S2P in one cycle T is 2S2P.
The length of the period 4P, that is, the period 2S2 of the period 4P
The ratio of P to P is such that the output voltage V ₀ × output current I ₀ maintains the value at the operating point B or operating point C while the output current I ₀ is maintained.
Is increased according to the amount exceeding the _second specified current value I ₂ . That is, the power supply device 2 is operated in the constant power mode.

Assuming that the current value four times the _first specified current value I ₁ is the third specified current value I ₃ , the period 2S2P and the period 4P are set.
When the output current I ₀ further increases from the state in which is mixed and reaches the third specified current value I ₃ , as shown in FIG. 12, the period 2S2P becomes zero and one period T is occupied by the period 4P. This state is the operating point D in FIG.

From the state at the operating point D, the output current I₀
If you try to increase the
The first to fourth sub-converters 7₁~ 7_FourH bridge circuit inside
The operating period of the constituent transistors is shortened. That is,
1st-4th secondary winding 23₁~ 23_FourThe period when the voltage is zero V
And the output current I increases₀As a result, the output voltage V ₀Is
descend. Output voltage V₀Is almost zero V
Move to point E.

As described above, in this power supply device 2,
The connection state of the _first to _fourth secondary windings 23 ₁ to 23 ₄ is gradually changed from 4 series to 4 parallel, and the output voltage V ₀ is decreased while increasing the output current I _0. There is.

In this case, since the magnitude of the voltage induced in each of the secondary windings 23 ₁ to 23 ₄ and the magnitude of the flowing current do not change and constant power is maintained, the current supplied to the load 28 is not changed. It is not necessary to design a transformer with the maximum value of and the maximum value of voltage.

[0073] In the above embodiment, the first to fifth rectifying element series circuits 31 ₁ to 31 ₅ which constitute the rectifier circuit 24,
Two rectifying elements 51A～55a, was constructed the 51b~55b connected in series, for example, a second rectifying element series circuit 31 ₂ in FIG. 14, two rectifying elements connected in parallel 52
As in a rectifier element series circuit in which a ₁ , 52a ₂ , 52b ₁ and 52b ₂ are connected in series, any rectifier element that constitutes a rectifier element series circuit has two or more rectifier elements. Can be connected in parallel.

Further, as the rectifying element forming each rectifying element series circuit, a MOSFET can be used as a diode in addition to the PN junction diode and the Schottky junction diode.

[0075] Furthermore, in addition to the present invention the transformer ₈₁ of the first to fourth, (the M 6 or more integer) fifth or more fifth to M may be added transformer. in this case,
M + 1 rectifying element series circuits are required.

Then, the phase of the AC voltage induced in the _first to Mth secondary windings 13 _{1 to} 13 _M in the _first to _Mth transformers 8 ₁ to 8 _M is controlled to control the first to the first Mth secondary windings 13 _{1 to} 13 _M. M secondary winding 13 ₁ to 1
When 3 _M are connected in series, M times the voltage output from one secondary winding is output, and when the first to M-th secondary windings 13 _{1 to} 13 _M are connected in parallel. Then, a current M times the current flowing through one secondary winding is output.

[0077]

By changing the phase that is easy to control, it is possible to reduce the output current while keeping the output power constant.

[Brief description of drawings]

FIG. 1 is an example of a power supply device of the present invention

FIG. 2 is a diagram for explaining how the current flows when the power supply device is in a 4-series connection period and a positive voltage is induced.

FIG. 3 is a diagram for explaining how a current flows when a negative voltage is induced during a 4-series connection period.

FIG. 4 is a diagram for explaining how a current flows when a positive voltage is induced during a two-series and two-parallel connection period.

FIG. 5 is a diagram for explaining how a current flows when a negative voltage is induced during a two-series and two-parallel connection period.

FIG. 6 is a diagram for explaining how a current flows when a positive polarity voltage is induced during a 4-parallel connection period.

FIG. 7 is a diagram for explaining how a current flows when a negative voltage is induced during a 4-parallel connection period.

FIG. 8 is a timing chart in the case where one cycle is a total of four series connection periods.

FIG. 9 is a timing chart when four series connection periods and two series and two parallel connection periods coexist.

FIG. 10 is a timing chart in the case where one cycle is a total of two series and two parallel connection periods.

FIG. 11 is a timing chart in the case where two series two parallel connection periods and four parallel connection periods coexist.

FIG. 12 is a timing chart in the case where one cycle is a total of four parallel connection periods.

FIG. 13 is a graph for explaining the relationship between the output current and the output voltage of the power supply device of the present invention.

FIG. 14 is an example of a power supply device in which rectifying elements forming a rectifying element series circuit are connected in parallel.

FIG. 15 shows an example of a conventional power supply device.

[Explanation of symbols]

2 ... Power supply device 7 ... Main converter 10 ... DC voltage source 13 _{1 to} 13 ₄ ...... First to fourth primary windings 23 ₁ to 23 ₄ ...... First to fourth secondary windings 24 ... Rectifying circuit 27 ... Smoothing circuit 31 _{1 to} 31 ₅ ...... First to fifth rectifying element series circuit 36 ...... Cathode connection point 37 ...... Anode connection points 51a to 55a, 51b to 55b ...... Rectification element a _{1 to} a ₅ ... 1st to 5th connection points 4S ... 4 series connection period 2S 2P ... 2 series 2 parallel connection period 4P ... 4 parallel connection period

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5H730 AA14 AS00 AS03 BB27 BB57                       BB85 BB88 BB91 DD04 EE08                       EE10 EE59 FD01 FG05 FG22

Claims (8)

[Claims] 1. A main converter that generates an alternating current from a direct-current voltage source, and first to first alternating currents that are supplied from the main converter, respectively.
A fourth primary winding, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, respectively, and induced in the first to fourth secondary windings. A rectifying circuit that rectifies an alternating voltage to output to a cathode connection point and an anode connection point, and a smoothing circuit that smoothes a voltage output to the cathode connection point and the anode connection point, wherein The rectifier circuit has first to fifth rectifier element series circuits in which rectifier elements are connected in series at first to fifth connection points, respectively, and the first to fourth secondary windings are arranged in this order. Both ends of a circuit that is connected in series and in which the first to fourth secondary windings are connected in series and a portion in which the first to fourth secondary windings are connected to each other are respectively the first to the first The cathode side and the anode side of the first to fifth rectifying element series circuits are connected to Are connected to each other at the anode connection point and the anode connection point, respectively, and the voltage generated at the cathode connection point and the anode connection point is
A power supply circuit configured to be smoothed by the smoothing circuit and supplied to a load. 2. The main converter controls the phase of an AC voltage induced in the first to fourth secondary windings, and during the operation period of the power supply circuit, the first to fourth secondary windings are controlled. The power supply circuit according to claim 1, wherein the power supply circuit is configured to include four series connection periods in which the voltages induced in the next winding are added and applied between the cathode connection point and the anode connection point. 3. The main converter controls the phase of an AC voltage induced in the first to fourth secondary windings, and the main converter converts the phases of the first to fourth secondary windings during an operation period of the power supply circuit. The voltage induced in the next winding is configured to include four parallel connection periods applied in parallel between the cathode connection point and the anode connection point. The power supply circuit described in the item. 4. The main converter controls the phase of an AC voltage induced in the first to fourth secondary windings, and during the operation period of the power supply circuit, the first to fourth secondary windings are controlled. The voltage of two windings of the next winding is added, and the added voltage includes two series and two parallel connection periods in which the added voltage is applied in parallel to the cathode connection point and the anode connection point. Claim 1
The power supply circuit according to claim 3. 5. First to fourth parts to which alternating currents are respectively supplied
Primary winding, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, and alternating current induced in the first to fourth secondary windings It has a rectifier circuit that rectifies the voltage and outputs it to the cathode connection point and the anode connection point, and smoothes the voltage output to the cathode connection point and the anode connection point to supply the output voltage of the power supply device to the load. A control method for controlling, wherein the voltages induced in the first to fourth secondary windings are added and output to the cathode connection point and the anode connection point.
2 in the series connection period and the voltage induced in the first to fourth secondary windings
Two series and two parallel periods in which the voltage obtained by adding the pieces is applied in parallel to the cathode connection point and the anode connection point are provided during the operation period of the power supply device, and the four series connection period and the two series two parallel connection A method of controlling a power supply device, wherein the ratio of periods is changed to control the magnitude of the output voltage. 6. First to fourth portions to which alternating currents are respectively supplied
Primary winding, first to fourth secondary windings magnetically coupled to the first to fourth primary windings, and alternating current induced in the first to fourth secondary windings It has a rectifier circuit that rectifies the voltage and outputs it to the cathode connection point and the anode connection point, and smoothes the voltage output to the cathode connection point and the anode connection point to supply the output voltage of the power supply device to the load. A control method for controlling, wherein, of the voltages induced in the first to fourth secondary windings, 2
The two series and two parallel periods in which the added voltage is applied in parallel to the cathode connection point and the anode connection point, and the voltages induced in the first to fourth secondary windings are connected in parallel to the cathode connection. Points and four parallel connection periods applied between the anode connection points during the operation period of the power supply device,
A method of controlling a power supply device, which controls the magnitude of the output voltage by changing the ratio of the 2-series 2-parallel connection period and the 4-parallel connection period. 7. A first to N-th supply of alternating current, respectively.
A primary winding (N is an integer of 4 or more), first to Nth secondary windings magnetically coupled to the first to Nth primary windings, respectively, and the first to Nth secondary windings. It has a rectifier circuit that rectifies the AC voltage induced in the next winding and outputs it to the cathode connection point and the anode connection point, and smoothes the voltage output to the cathode connection point and the anode connection point to the load. A control method for controlling an output voltage of a power supply device to be supplied, wherein the voltages induced in the first to Nth secondary windings are added according to the magnitude of an output current to add the cathode connection point and the anode. Power supply device for switching between N series connection operation for outputting to the connection point and N parallel operation for outputting the voltage induced in the first to Nth secondary windings in parallel to the cathode connection point and the anode connection point Control method. 8. A series-parallel connection operation for connecting two or more secondary windings in parallel according to the magnitude of the output current during the transition from the N series connection operation to the N parallel connection operation. Item 7. A method of operating a power supply device according to item 7.