JPWO2013038512A1 - Multiple chopper device - Google Patents

Abstract

A current detector (12) detects a current flowing in the same wiring component of a plurality of chopper devices (100A, 100B) connected in parallel, and the detected current waveform is processed by a current waveform processing unit (13). A current deviation signal (ΔI) representing a current deviation between the chopper devices (100A, 100B) and a switching signal correction unit for the switching signals (Sa *, Sb *) generated by the switching signal generation unit (21). (22) corrects the current deviation between the chopper devices (100A, 100B) based on the current deviation signal (ΔI).

Description

  The present invention relates to a multiple chopper device in which a plurality of chopper devices combining a semiconductor element and a reactor are connected in parallel, and particularly to a technique for reducing current imbalance (current deviation) between a plurality of chopper devices connected in parallel. It is.

  As a multiple chopper device used for DC conversion from the low voltage side to the high voltage side or from the high voltage side to the low voltage side, a plurality of chopper devices are connected in parallel, and each chopper device is driven with a phase difference of (2π / number of parallel). There are multiple chopper devices. This multi-chopper device has an advantage that it is possible to reduce the size of a capacitor or the like because driving with a phase difference as described above reduces current ripple as compared with a case where the multi-chopper device is not connected in parallel.

  However, when the chopper devices are connected in parallel as described above, an unbalance of the shared current between the parallel chopper devices occurs due to characteristic variations of the switching elements, their drivers, reactors, and the like constituting each chopper device. . When such a current imbalance occurs, there arises a disadvantage that it leads to an overcurrent breakdown due to current concentration and an overtemperature breakdown due to heat generation concentration. Therefore, it is necessary to equalize the current between the parallel chopper devices.

  Therefore, in the prior art, when multiple chopper devices are connected in parallel, for example, when composed of two chopper devices, the output current of each chopper device is detected by a current detector provided individually for each chopper device, Based on these detected currents, the calculator calculates the difference between the output currents of the two chopper devices. Then, a high-frequency component is removed from each output current difference waveform by a low-pass filter to generate a current deviation signal representing a current deviation between the two chopper devices and input it to the control unit.

  The control unit that drives and controls each chopper device generates two switching signals by a PWM (pulse width modulation) method by comparing the magnitude relationship between the output voltage command value and the two carrier waves for which the phase difference is set. Each switching signal is output to each chopper device. At that time, the control unit reduces the current imbalance between the two chopper devices according to the current deviation signal input through the low-pass filter as described above. The on / off time of the switching signal is changed by adjusting the offset of the carrier wave of one of the chopper devices. Thus, the output current of the chopper device that receives the switching signal whose on / off time has changed rises or falls according to the direction of the change of the on / off time, thereby reducing current imbalance among the chopper devices. (For example, refer to Patent Document 1 below).

JP 2010-273470 A

  The conventional multi-chopper device can reduce current imbalance. However, the control unit needs to perform both generation of a switching signal by a PWM method for driving each chopper device and adjustment of the offset of the carrier wave to reduce current imbalance between the chopper devices. Therefore, the control time from the detection of the output current of each chopper device by the current detector to the output by adjusting the ON / OFF period of the switching signal for each chopper device by the control unit is lengthened and the current imbalance is reduced. There is a problem that there is a large delay in control to do this. In addition, if the design of the control unit is changed, it is necessary to newly adjust the offset for the carrier wave for generating the switching signal, and the overall influence due to the design change of the control unit is large, and extra labor and labor are required. There was a problem.

  The present invention has been made to solve the above-described problems. The control delay for reducing the current imbalance between the chopper devices is small, and the design of each circuit unit is changed. It is another object of the present invention to provide a multiple chopper device that has a small overall influence and can reduce extra labor and labor.

A multi-chopper device according to the present invention comprises a reactor connected to a low-voltage side, a switching element connected to the reactor, and a chopper device composed of a diode connected in parallel (N is an integer of 2 or more) in parallel. DC switching is performed between the low voltage side and the high voltage side by turning on and off the switching elements of the chopper device with a phase difference between each other,
In the location of the same wiring component constituting each of the chopper devices, a current detector for detecting a difference in current flowing in the same wiring component when sharing the DC conversion in each chopper device is provided,
A switching signal generator for generating a switching signal for driving the device for each of the chopper devices;
A current waveform processing unit that processes a current waveform detected by the current detector and generates a current deviation signal that represents a current deviation between the chopper devices;
A switching signal correction unit that corrects the switching signal generated by the switching signal generation unit so as to reduce current imbalance between the chopper devices based on the current deviation signal generated by the current waveform processing unit. ing.

  According to the multiple chopper device of the present invention, the generation of the switching signal for driving each chopper device and the control for changing the ON / OFF time of the switching signal in order to reduce the current imbalance can be performed independently. Therefore, the control delay for reducing the current imbalance between the chopper devices is small, and even if the design of each circuit part is changed, the overall effect is small, and extra effort and labor are required. It is possible to provide a multiple chopper device that can be reduced.

1 is a circuit diagram showing a step-up type multiple chopper device according to Embodiment 1 of the present invention. FIG. Waveform showing switching signal of each chopper device, current flowing through reactor, detected current detected by current detector, and current deviation signal obtained by current waveform processing unit when current imbalance occurs between each chopper device FIG. It is a wave form diagram when performing duty correction to a switching signal by a switching signal correction part. It is a wave form diagram in case another duty correction is performed to a switching signal by a switching signal correction part. It is a circuit diagram which shows the pressure | voltage fall type | mold multiple chopper apparatus as a modification of Embodiment 1 of this invention. It is a circuit diagram which shows the modification of the arrangement | positioning location of the wire bundle and current detector of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the modification of the arrangement | positioning location of the wire bundle and current detector of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the modification of the arrangement | positioning location of the wire bundle and current detector of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the modification of the arrangement | positioning location of the wire bundle and current detector of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the modification of the current waveform process part of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the other modification of the current waveform process part of the pressure | voltage rise type | mold multiple chopper apparatus in Embodiment 1 of this invention. It is a circuit diagram which shows the bidirectional | two-way multiple chopper apparatus in Embodiment 2 of this invention. It is a circuit diagram which shows the synchronous rectification type | mold multiple chopper apparatus as a modification of Embodiment 2 of this invention. It is a circuit diagram which shows the bidirectional | two-way multiple chopper apparatus in Embodiment 3 of this invention. It is a circuit diagram which shows the synchronous rectification type | mold multiple chopper apparatus as a modification of Embodiment 3 of this invention. It is a circuit diagram which shows the pressure | voltage rise type multiple chopper apparatus in Embodiment 4 of this invention.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

Embodiment 1 FIG.
1 is a circuit diagram showing a multiple chopper device according to Embodiment 1 of the present invention.
The multiple chopper device according to the first embodiment is of a boost type that boosts DC power from a battery 1 serving as a low-voltage DC power source to a load 2 on a high-voltage side. In this multiple chopper device, two chopper devices 100A and 100B are connected in parallel between a battery 1 and a load 2, and smoothing capacitors 3 and 4 are connected in parallel to the battery 1 and the load 2, respectively. The multiple chopper device also includes a current detector 12, a current waveform processing unit 13, and a control unit 20 that drives and controls the chopper devices 100A and 100B.

  Here, the first chopper device 100A includes a reactor 5A, an upper arm diode 8A, a lower arm diode 9A, a lower arm switching element 7A, and a driver 17A that drives the switching element 7A. Similarly, the second chopper device 100B includes a reactor 5B, an upper arm diode 8B, a lower arm diode 9B, a lower arm switching element 7B, and a driver 17B that drives the switching element 7B.

  The control unit 20 outputs the switching signals Sa and Sb instructing on and off of the switching elements 7A and 7B to the drivers 17A and 17B, whereby the chopper devices 100A and 100B are driven with a phase difference of π. The In control called PWM control (Pulse Width Modulation), the total time of the on time and off time of the switching elements 7A and 7B is constant, and is called a switching cycle. The ratio of on-time to switching period is called duty. The control unit 20 controls the DC voltage conversion rates of the chopper devices 100A and 100B by changing the duty of the switching signals Sa and Sb output to the drivers 17A and 17B of the chopper devices 100A and 100B.

  A feature of the multiple chopper device of the first embodiment is that the wires of the reactors 5A and 5B are selected as the same wiring parts of the two chopper devices 100A and 100B, and the switching element 7A and the like are selected from the reactor 5A of the first chopper device 100A. A pair of wires through which these currents flow so that the direction of the current flowing toward the diode 8A and the direction of the current flowing from the reactor 5B of the second chopper device 100B toward the switching element 7B and the diode 8B are reversed. The wiring bundle 11 is formed by superimposing. Then, a current detector 12 that can detect the current flowing through the electric wire or bus bar in a non-contact manner including a direct current component is installed in the wiring bundle 11. As the current detector 12 in this case, for example, DCCT, Hall CT, Hall current sensor or the like is applied.

  With the above configuration, the current detector 12 has the same wiring of the chopper devices 100A and 100B at the location of the wiring bundle 11, and the wiring of the reactor 5A of the chopper device 100A and the reactor 5B of the chopper device 100B. A difference in current flowing through the wiring is detected. Hereinafter, the current detected by the current detector 12 at the location of the wiring bundle 11 is simply referred to as a detection current Id.

  The maximum current value of the detection current Id detected by the current detector 12 at the location of the wiring bundle 11 is generally larger than the maximum current value of the current flowing individually through the wires of the reactors 5A and 5B of the chopper devices 100A and 100B. small. Therefore, the maximum measurable current value of the current detector 12 can be made smaller than the value when the current flowing through the wiring of each reactor 5A is individually detected by the current detector. As a result, the detection current Id can be detected with high accuracy using the high-resolution current detector 12, and the number of current detectors 12 can be reduced.

  Here, the current waveform processing unit 13 includes a low-pass filter 131, removes a ripple component from the waveform of the detection current Id of the current detector 12, and generates a DC component as the current deviation signal ΔI. The current deviation signal ΔI generated by the current waveform processing unit 13 is input to the control unit 20.

Next, the state of each part when current imbalance occurs between the chopper devices 100A and 100B will be described.
FIG. 2 shows the switching signals Sa and Sb applied to the drivers 17A and 17B of the chopper devices 100A and 100B and the current Ia flowing through the reactors 5A and 5B when current imbalance occurs between the chopper devices 100A and 100B. , Ib, the detected current Id (= Ia−Ib) detected by the current detector 12, and the current deviation signal ΔI output from the current waveform processing unit 13 are shown. The currents Ia and Ib flowing through the reactors 5A and 5B have a positive direction from the battery 1 to the load 2. Regarding the sign of the detected current Id detected by the current detector 12, the current detector 12 determines the sign of the difference between the current Ia flowing through the reactor 5A and the current Ib flowing through the reactor 5B.

  As can be seen from FIG. 2, since the current Ia flowing through the reactor 5A of the first chopper device 100A is larger than the current Ib flowing through the reactor 5B of the second chopper device 100B, the current is unbalanced, and one current Ia The peak of the waveform is higher than the peak of the waveform of the other current Ib.

  Thus, since the current Ia flowing through the reactor 5A of the first chopper device 100A is larger than the current Ib flowing through the reactor 5B of the second chopper device 100B, the current waveform processing unit 13 obtains it. The waveform of the current deviation signal ΔI (DC component) to be generated is above the zero ampere line. The larger the current unbalanced state between the chopper devices 100A and 100B, the greater the deviation of the waveform of the current deviation signal ΔI from the zero ampere line. And the control part 20 determines the direction (positive / negative) and magnitude | size of the current imbalance state between chopper apparatus 100A, 100B by inputting the current deviation signal (DELTA) I which the current waveform process part 13 produces | generates. it can.

Next, the configuration of the control unit 20 will be described.
In the control unit 20, a switching signal generation unit 21 and a switching signal correction unit 22 are provided independently. The switching signal generation unit 21 performs switching cycle setting and phase difference setting between the chopper devices 100A and 100B, and switching with a predetermined duty for the drivers 17A and 17B of the chopper devices 100A and 100B based on the input / output voltage setting. Signals Sa * and Sb * are generated. The switching signal correction unit 22 receives the current deviation signal ΔI generated by the current waveform processing unit 13, and determines the direction and magnitude of the current unbalanced state between the chopper devices 100A and 100B based on the current deviation signal ΔI. In accordance with this determination, duty correction is performed on the switching signals Sa * and Sb * generated by the switching signal generation unit 21 so as to reduce the current unbalanced state between the chopper devices 100A and 100B. The switching signals Sa and Sb after duty correction are output to the drivers 17A and 17B of the chopper devices 100A and 100B. Hereinafter, the content of the duty correction by the switching signal correction unit 22 will be described based on a specific example with reference to FIG.

  Here, it is assumed that the DC component of current Ia flowing through reactor 5A of first chopper device 100A is 16 amperes, and the DC component of current Ib flowing through reactor 5B of second chopper device 100B is 10 amperes.

  The current waveform processing unit 13 processes the current waveform of the detected current Id (= Ia−Ib) detected by the current detector 12 so that the current Ia of the reactor 5A of the chopper device 100A is greater than the current Ib of the reactor 5B of the chopper device 100B. Produces a current deviation signal ΔI representing 6 amps higher. The switching signal correction unit 22 receives the current deviation signal ΔI generated by the current waveform processing unit 13 and outputs the switching signals Sa * and Sb * generated by the switching signal generation unit 21 based on the current deviation signal ΔI. The following correction is performed.

  That is, for the switching signal Sa * related to the driver 17A of the first chopper device 100A, the duty is corrected so as to be shortened so that the on-time is shortened so that the current flowing through the reactor 5A is reduced by 3 amperes. On the other hand, the switching signal Sb * related to the driver 17B of the second chopper device 100B is corrected so as to increase the duty so that the ON time becomes longer, and the current flowing through the reactor 5B is increased by 3 amperes.

  Although not shown, the duty correction by the switching signal correction unit 22 is performed by combining, for example, an RC filter and a comparator. That is, after passing each switching signal Sa *, Sb * from the switching signal generation unit 21 through an RC filter whose time constant is about 1/20 to 1/20 of the switching period, it is applied to one input terminal of the comparator. By inputting the current deviation signal ΔI as a reference signal to the other input terminal of the comparator, comparing the two signals with the comparator, performing signal processing such as reshaping into a square wave and outputting it, etc. Can be realized.

  As described above, the switching signal correction unit 22 performs duty correction on both of the switching signals Sa * and Sb * generated by the switching signal generation unit 21, and uses the corrected switching signals Sa and Sb as chopper devices 100A and 100B. By outputting to the drivers 17A and 17B, the current imbalance between the chopper devices 100A and 100B can be reduced without the total output current from the chopper devices 100A and 100B to the load 2 changing. .

  In addition, since the generation of the switching signal by the switching signal generation unit 21 and the correction of the switching signal by the switching signal correction unit 22 are performed independently, the current unbalanced state between the chopper devices 100A and 100B is reduced. Therefore, even if the control delay is small, and the design of each circuit unit is changed, the overall influence is small, and extra labor and labor can be reduced.

  In the example shown in FIG. 3, the duty correction is applied to both the switching signals Sa * and Sb * related to the drivers 17A and 17B of the chopper devices 100A and 100B. However, the present invention is not limited to this. For example, as shown in FIG. 4, duty correction for the switching signal Sb * to the second chopper device 100B is omitted, and duty is only applied to the switching signal Sa * to the first chopper device 100A. Corrections may be made.

  That is, duty correction is not performed on the switching signal Sb * related to the driver 17B of the second chopper device 100B, and the on-time is shortened only for the switching signal Sa * related to the driver 17A of the first chopper device 100A. The current Ia flowing through the reactor 5A of the first chopper device 100A may be reduced by 6 amperes by performing a correction that reduces the duty. While the current imbalance state between the chopper devices 100A and 100B is reduced, the number of parts of the switching signal correction unit 22 is suppressed, and the cost can be reduced.

The following various modifications can be made to the first embodiment.
Modification 1
In FIG. 1, a boost type multiple chopper device that boosts DC power from a low voltage side battery 1 to a high voltage side load 2 has been described as an example. However, the present invention is not limited to this, and for example, as shown in FIG. 5. The present invention can also be applied to a step-down multiple chopper device that steps down DC power from a high-voltage battery 1 to a low-voltage load 2.

  That is, FIG. 5 shows a step-down type multiple chopper device having a multiplexing number of “2” in which two chopper devices 100A and 100B are connected in parallel between a high voltage side battery 1 and a low voltage side load 2. Is shown. In FIG. 5, the first chopper device 100A includes a reactor 5A, a lower arm diode 9A, an upper arm switching element 6A, an upper arm diode 8A, and a driver 16A that drives the switching element 6A. Similarly, the second chopper device 100B includes a reactor 5B, a lower arm diode 9B, an upper arm switching element 6B, an upper arm diode 8B, and a driver 16B that drives the switching element 6B. Since the other configuration is the same as that of the step-up type multiple chopper device shown in FIG. 1, detailed description thereof is omitted here.

  In the step-down multiple chopper device shown in FIG. 5 as well, the switching signal correction unit 22 constituting the control unit 20 receives the current deviation signal ΔI generated by the current waveform processing unit 13 and receives the current difference between the chopper devices 100A and 100B. Since the direction and magnitude of the balance state are determined and the switching signal generated by the switching signal generation unit 21 is corrected so as to reduce the current imbalance between the two chopper devices 100A and 100B, it is shown in FIG. As in the case, the operation and effect of the present invention can be obtained.

Modification 2
In the multi-chopper device shown in FIG. 1 or FIG. 5, the wires of the reactors 5A and 5B are selected as the same wiring parts that cause a current difference between the chopper devices 100A and 100B, and the direction of the current flowing out from each wire is reversed. A wiring bundle 11 composed of a pair of wirings is formed by superimposing the wiring bundles so as to face each other, and a current detector 12 is installed at a place where the wiring bundle 11 is formed to obtain a detection current Id representing a current difference flowing through each wiring. I am doing so. In the present invention, it is not always necessary to select the respective wirings of the reactors 5A and 5B. By selecting the same wiring parts of the chopper devices 100A and 100B as follows, a pair of wiring bundles 11 are formed to detect the current. A vessel 12 may be installed.

  That is, as shown in FIG. 6, as the same wiring component of each chopper device 100A, 100B, the input wiring of each chopper device 100A, 100B is selected and superimposed so that the direction of the current flowing out from the input wiring is reversed. Thus, the wiring bundle 11 is formed. Then, a current detector 12 may be installed at a place where the wiring bundle 11 is formed, and a difference in current flowing through each input wiring may be obtained as the detection current Id.

  Further, as shown in FIG. 7, as the same wiring component of each chopper device 100A, 100B, the output wiring of each chopper device 100A, 100B is selected and superposed so that the direction of the current flowing out from the output wiring is reversed. Thus, the wiring bundle 11 is formed. Then, a current detector 12 may be installed at a place where the wiring bundle 11 is formed, and a difference in current flowing through each output wiring may be obtained as the detection current Id.

  Further, as shown in FIG. 8, the main current wiring of the switching elements 7A and 7B of each chopper device 100A and 100B is selected as the same wiring component of each chopper device 100A and 100B, and the main current of each switching element 7A and 7B is selected. The wiring bundle 11 is formed by overlapping so that the direction of the current flowing out from the current wiring is reversed. Then, a current detector 12 may be installed at a place where the wiring bundle 11 is formed, and the difference between the currents flowing through the main current wirings of the switching elements 7A and 7B may be obtained as the detection current Id.

  Further, as shown in FIG. 9, the wiring of the diodes 8A and 8B of the chopper devices 100A and 100B is selected as the same wiring component of the chopper devices 100A and 100B, and the direction of the current flowing out from the wiring of the diodes 8A and 8B The wiring bundle 11 is formed by superimposing them so as to be opposite to each other. Then, a current detector 12 may be installed at a place where the wiring bundle 11 is formed, and a difference between currents flowing through the wirings of the diodes 8A and 8B may be obtained as the detection current Id.

Modification 3
In FIGS. 1 and 5, the current detector 12 is provided at the location where the wire bundle 11 composed of a pair of wires is formed, and the current waveform processing unit 13 is configured by the low-pass filter 131. It is good also as a structure as shown in FIG.

That is, in the case of FIG. 10, the wires of the reactors 5A and 5B are selected as the same wiring parts of the chopper devices 100A and 100B, and the current detectors 12A and 12B are individually provided for each wiring. The current waveform processing unit 13 includes a low-pass filter 131 and a calculator 132. Then, the currents flowing through the reactors 5A and 5B of the chopper devices 100A and 100B are detected by the current detectors 12A and 12B, and the detected currents Ida and Idb are input to the calculator 132 of the current waveform processing unit 13, so that both currents A current difference is obtained by subtracting Ida and Idb. Next, a ripple component is removed by the low-pass filter 131 to generate a direct current component of a current difference as a current deviation signal ΔI, and this current deviation signal ΔI is input to the control unit 20.
According to this configuration, although the number of current detectors 12A and 12B is increased, it is not necessary to form the wire bundle 11 composed of a pair of wires, so that the main circuit wiring can be easily handled.

Modification 4
In the case of FIG. 10, the detection currents Ida and Idb obtained by the current detectors 12A and 12B are first input to the calculator 132, and then the current deviation signal ΔI is generated through the low-pass filter 131. Yes. On the other hand, as shown in FIG. 11, in the current waveform processing unit 13, the detected currents Ida and Idb obtained by the current detectors 12A and 12B are first individually input to the low-pass filters 131A and 131B, and ripple components are input. Then, a DC component is generated, and then the DC component of each of the detected currents Ida and Idb is input to the calculator 132 to obtain a difference between the two to generate a current deviation signal ΔI. You may make it input into the control part 20. FIG.
According to this configuration, the computing unit 132 constituting the current waveform processing unit 13 performs a subtraction process on the DC component waveform, so that the current deviation signal ΔI can be generated even using the computing unit 132 having poor high frequency characteristics. The current waveform processing unit 13 can be configured at low cost.

Modification 5
In the case of FIGS. 10 and 11, the wires of the reactors 5A and 5B are selected as the same wiring parts of the chopper devices 100A and 100B, and the currents flowing through the wires of the reactors 5A and 5B are detected by the current detectors 12A and 12B. I did it. However, the present invention is not limited thereto, and switching elements 7A and 7B are selected as the same wiring parts of the chopper devices 100A and 100B, and the main currents flowing through the switching elements 7A and 7B are detected by the current detectors 12A and 12B, respectively. You can also. Alternatively, the upper arm diodes 8A and 8B can be selected as the same wiring components of the chopper devices 100A and 100B, and the currents flowing through the diodes 8A and 8B can be detected by the current detectors 12A and 12B. Furthermore, the input current or the output current of each chopper device 100A, 100B may be detected by the current detectors 12A, 12B, respectively.

Modification 6
The switching signal correction unit 22 in the control unit 20 performs duty correction on the switching signals Sa * and Sb * generated from the switching signal generation unit 21 in order to reduce current imbalance between the chopper devices 100A and 100B. However, it is desirable to limit the amount of correction in that case.

  That is, for example, consider a case where the second chopper device 100B fails, the current flowing through the wiring components of the chopper device 100B becomes zero amperes, and the current supply from the chopper device 100B to the load 2 is interrupted. At this time, if the switching signal correction unit 22 does not limit the correction amount for correcting the switching signals Sa * and Sb *, the switching signal correction unit 22 has zero current flowing through the wiring components of the first chopper device 100A. The switching signal Sa * generated by the switching signal generation unit 21 is corrected so as to be amperage. As a result, not only the current supply from the chopper device 100B causing the failure to the load 2 but also the current supply from the chopper device 100A not causing the failure to the load 2 is interrupted. On the other hand, if the correction amount of the duty correction for the switching signals Sa * and Sb * of the switching signal correction unit 22 is limited, even if the second chopper device 100B fails, the chopper device that does not cause the failure. The current supply from 100 A to the load 2 does not decrease to zero amperes, and the current supply to the load 2 can be continued.

Modification 7
As the switching elements 6A, 6B, 7A, 7B used in the chopper devices 100A, 100B, semiconductor elements that can be turned on / off, such as IGBTs and MOSFETs, can be applied, and as the diodes 8A, 8B, 9A, 9B, In addition to a PiN diode and a Schottky barrier diode, for example, a body diode of a MOSFET can be applied.
As for the semiconductor materials of the switching elements 6A, 6B, 7A, 7B and the diodes 8A, 8B, 9A, 9B, a wide band gap semiconductor having a band gap larger than that of silicon can be used in addition to the widely used silicon. Good. Examples of the wide band gap semiconductor include silicon carbide, a gallium nitride-based material, and diamond. When a wide bandgap semiconductor is used as the semiconductor material of the switching elements 6A, 6B, 7A, 7B, it is made of silicon used in the chopper device due to the material characteristics of the wide bandgap semiconductor such as high withstand voltage and high allowable current density. The IGBT can be replaced with a wide band gap semiconductor MOSFET. The voltage between the main terminals when the MOSFET is on increases as the element temperature increases. When the input current and output current of each chopper device 100A, 100B increase, the temperature of the switching elements 6A, 6B, 7A, 7B rises, and the on-resistance increases, thereby preventing the current imbalance from expanding. Since the current unbalance reduction control function is assisted, the gain of the control feedback loop can be reduced, and stable current unbalance reduction control can be performed. When a wide band gap semiconductor is used as the semiconductor material of the diodes 8A, 8B, 9A, 9B, silicon-made PiN used in the chopper device due to the material characteristics of the wide band gap semiconductor such as high withstand voltage and high allowable current density. The diode can be replaced with a Schottky barrier diode made of a wide band gap semiconductor. The forward voltage drop of the Schottky barrier diode increases as the element temperature increases. When the input current and output current of each chopper device 100A, 100B increase, the temperature of the diodes 8A, 8B, 9A, 9B increases, and the forward voltage drop increases, thereby preventing the current imbalance from expanding. As described above, since the control function for reducing the current imbalance is assisted, the gain of the control feedback loop can be reduced, and the stable control for reducing the current imbalance can be achieved.

Modification 8
In the first embodiment, the multiplex chopper apparatus having a multiplexing number of “2” has been described as an example. However, the present invention is not limited to this, and is applied to a multiplex chopper apparatus having a multiplexing number of “3” or more. can do.

Embodiment 2. FIG.
FIG. 12 is a circuit diagram showing a multiple chopper device according to the second embodiment of the present invention. Components corresponding to or corresponding to those of the first embodiment shown in FIG.

  The multiple chopper device of the second embodiment is a bidirectional type that converts DC power by bidirectionally passing between the low voltage side battery 1 and the high voltage side load 2. Two chopper devices 100A and 100B are connected in parallel between the load 2 on the side. The multiple chopper device according to the second embodiment includes a current detector 12, a current waveform processing unit 13, and a control unit 20 that drives and controls the chopper devices 100A and 100B.

  12, a first chopper device 100A includes a reactor 5A, an upper arm diode 8A and a switching element 6A, a driver 16A for driving the switching element 6A, a lower arm diode 9A and a switching element 7A, and the switching element 7A. It is comprised from the driver 17A which drives. Similarly for the second chopper device 100B, the reactor 5B, the upper arm diode 8B and the switching element 6B, the driver 16B for driving the switching element 6B, the lower arm diode 9B and the switching element 7B, and the switching element It comprises a driver 17B that drives 7B.

  The control unit 20 outputs PWM control switching signals Sa1, Sa2, Sb1, and Sb2 for commanding on / off of the switching elements 6A, 7A, 6B, and 7B to the drivers 16A, 17A, 16B, and 17B. Thus, the chopper devices 100A and 100B are driven with a phase difference of π.

  Also in the second embodiment, as in the first embodiment, the direction of the current flowing from the reactor 5A of the first chopper device 100A toward the switching element 7A or the diode 8A and the reactor 5B of the second chopper device 100B. The wiring bundle 11 is formed by superposing a pair of wirings through which these currents flow so that the direction of the current flowing from the switching element 6B to the switching element 6B and the diode 8B is reversed. A current detector 12 is installed in the wiring bundle 11. Thus, as in the first embodiment, the current detector 12 detects the difference between the current flowing through the reactor 5A of the first chopper device 100A and the current flowing through the reactor 5B of the second chopper device 100B. Detected as current Id.

  The current waveform processing unit 13 includes a low-pass filter 131, removes a ripple component from the detection waveform of the current detector 12, generates a DC component as a current deviation signal ΔI, and this current deviation signal ΔI is sent to the control unit 20. Entered.

Next, the configuration of the control unit 20 will be described.
As in the first embodiment, the control unit 20 includes a switching signal generation unit 21 and a switching signal correction unit 22 independently of each other.

  The switching signal generation unit 21 according to the second embodiment performs switching period setting and phase difference setting between the chopper devices 100A and 100B, and each driver 16A, 17A of each chopper device 100A, 100B based on input / output voltage setting. Switching signals Sa1 *, Sa2 *, Sb1 *, and Sb2 * having a predetermined duty related to 16B and 17B are generated. In addition, the switching signals Sa1 * and Sa2 * and the switching signals Sb1 * and Sb2 * to the switching elements 6A and 7A and the switching elements 6B and 7B belonging to the same arm are turned up and down at the time of switching on and off. The switching elements 6A and 7A and the switching elements 6B and 7B are provided with a dead time for giving an OFF command.

  Regarding the dead time in this case, if the dead time is short, an arm short circuit may occur and the components of the chopper device may be damaged. On the other hand, if the dead time is too long, the following problems occur. In the bidirectional multiple chopper device, the DC power is boosted and sent from the low voltage side battery 1 to the high voltage side load 2, and the DC power is stepped down from the high voltage side load 2 to the low voltage side battery 1 for regeneration. It is possible to continuously switch between the states to be performed by controlling the duty of the switching signal. Here, if the dead time is too long, the difference between the duty of the switching signals Sa1 * and Sb1 * related to the upper arm switching elements 6A and 6B and the duty of the switching signals Sa2 * and Sb2 * related to the lower arm switching elements 7A and 7B. Becomes larger. The difference between the voltage conversion rate in the step-up state and the voltage conversion rate in the step-down state becomes large, and the operation of the chopper devices 100A and 100B becomes unstable when switching between the step-up state and the step-down state. Thus, the dead time set for the switching signals Sa1 * and Sa2 * and the switching signals Sb1 * and Sb2 * to the switching elements 6A and 7A, switching elements 6B and 7B belonging to the same arm is suitable for the dead time. It is essential that the control unit 20 outputs the switching signal to the chopper devices 100A and 100B with the designed predetermined dead time length.

  In addition, the switching signal correction unit 22 in the control unit 20 receives the current deviation signal ΔI generated by the current waveform processing unit 13, and based on the current deviation signal ΔI, the current unbalanced state between the chopper devices 100A and 100B. Determine the orientation and size. Then, the switching signal correction unit 22 switches the switching signals Sa1 * and Sa2 * and the switching signal Sb1 * generated by the switching signal generation unit 21 so that the current balance state between the chopper devices 100A and 100B is reduced based on this determination. And Sb2 * are subjected to duty correction, and the duty-corrected switching signals Sa1, Sa2, Sb1, and Sb2 are output to the drivers 16A, 17A, 16B, and 17B of the chopper devices 100A and 100B.

  In this case, the content of the duty correction performed by the switching signal correction unit 22 is basically the same as that described in the first embodiment. The switching signals 6A and 7A of the same arm generated by the switching signal generation unit 21, switching signals Sa1 * and Sa2 * to the switching elements 6B and 7B, and switching signals Sb1 * and Sb2 * have a dead time. However, adjustment is made in advance so that the length of the dead time is not changed by the correction performed by the switching signal correction unit 22.

  Even when the switching elements 6A and 7A and the switching elements 6B and 7B of the upper and lower arms are turned on and off by providing a dead time as in the bidirectional multiple chopper apparatus of the second embodiment, the distance between the chopper apparatuses 100A and 100B Current unbalance and a control delay for reducing the current unbalance state can be reduced. Furthermore, since the switching signal generation by the PWM method and the control for changing the ON / OFF time of the switching signal are independently performed in order to reduce the current imbalance, the overall influence due to the design change is small and extra. Can save time and effort.

  The multi-chopper device shown in FIG. 12 is a bi-directional multi-chopper device that converts DC power through bidirectional flow between the low-voltage side battery 1 and the high-voltage side load 2. Unidirectional flow type switching elements 6A, 7A, 6B, 7B such as IGBTs are used, but not limited to this, a synchronous rectification type multiple chopper device that performs synchronous rectification using a bidirectional flow switch It is also possible to apply to.

FIG. 13 is a circuit diagram of the synchronous rectification type multiple chopper device.
The basic configuration in this case is the same as that shown in FIG. 12, but a bidirectional flow switch is employed for the switching elements 6A, 7A, 6B, and 7B. In this case, the bidirectional flow switch is a switch that allows a current to flow with low resistance not only in the forward direction but also in the reverse direction of the switching element when an ON command signal is input to the gate driver, such as a MOSFET. Say.

In the synchronous rectification type multiple chopper device shown in FIG. 13, during the period in which the return current flows through each of the diodes 8A, 9A, 8B, 9B, the bidirectional communication connected to each of the diodes 8A, 9A, 8B, 9B in parallel. Each switching element 6A, 7A, 6B, 7B which is a flow switch is turned on. Compared to the case where the return current is shunted through the diodes 8A, 9A, 8B, and 9B and the switching elements 6A, 7A, 6B, and 7B, and all the return current is passed through the diodes 8A, 9A, 8B, and 9B alone. The voltage drop of the reflux current is reduced. As described above, when a known synchronous rectification technique is used, the entire conduction loss can be reduced in the multiple chopper device that performs boosting, the multiple chopper device that performs step-down, and the multiple chopper device that performs boosting and step-down in both directions. .
Other configurations and operations are the same as those in the configuration shown in FIG. 12, and thus detailed description thereof is omitted here.

  12 and 13 according to the second embodiment, various modifications similar to those of the second to eighth modifications pointed out in the first embodiment can be applied. It is.

Embodiment 3 FIG.
FIG. 14 is a circuit diagram showing the configuration of the multiple chopper device according to the third embodiment of the present invention. Components corresponding to or corresponding to those of the second embodiment shown in FIG.

  The multiple chopper device according to the third embodiment is a bidirectional type that converts DC power through bidirectional flow between the low-voltage side battery 1 and the high-voltage side load 2, and is connected to each other in parallel. The configurations of the chopper devices 100A and 100B are basically the same as those in the second embodiment shown in FIG. Further, for the wires of the reactors 5A and 5B of the chopper devices 100A and 100B, a wire bundle 11 is formed by superposing these pair of wires so that the directions of the currents are opposite to each other. It is the same as that of Embodiment 2 that the vessel 12 is installed. Furthermore, since the configuration of the current waveform processing unit 13 is the same as that of the second embodiment, detailed description thereof is omitted here.

  The third embodiment is different from the second embodiment shown in FIG. 12 in the configuration of the control unit 20. That is, the control unit 20 of the third embodiment further includes an upper and lower arm signal generation unit 23 in addition to the switching signal generation unit 21 and the switching signal correction unit 22.

  Here, the switching signal generation unit 21 performs the switching cycle setting and the phase difference setting between the chopper devices 100A and 100B, and the switching elements 7A of the lower arms of the chopper devices 100A and 100B based on the input / output voltage settings. The switching signals Sa2 * and Sb2 * related to the drivers 17A and 17B of 7B are generated.

  The switching signal correction unit 22 receives the current deviation signal ΔI generated by the current waveform processing unit 13, and determines the direction and magnitude of the current unbalanced state between the chopper devices 100A and 100B based on the current deviation signal ΔI. Then, based on this determination, duty correction is performed on the two switching signals Sa2 * and Sb2 * generated by the switching signal generation unit 21 so that the current balance state between the chopper devices 100A and 100B is reduced.

  The upper and lower arm signal generation unit 23 generates four switching signals Sa1, Sa2, Sb1, and Sb2 based on the two switching signals Sa2 and Sb2 that have been subjected to duty correction by the switching signal correction unit 22, and each of these switching signals The signals Sa1, Sa2, Sb1, and Sb2 are output to the drivers 6A, 7A, 6B, and 7B of the chopper devices 100A and 100B, respectively.

  That is, the upper and lower arm signal generator 23 gives a delay time to the switching signal Sa <b> 2 given to the lower arm driver 17 </ b> A whose duty has been corrected by the switching signal corrector 22 and outputs it. The length of the on time and the length of the off time of the switching signal Sa2 are not changed. The upper and lower arm signal generator 23 outputs the switching signal Sa1 off to the upper arm driver 16A before outputting the switching signal Sa2 on the lower arm driver 17A, and both the switching signals Sa1 and Sa2 are off. A dead time is provided. After the switching signal Sa2 of the lower arm driver 17A is output OFF, the switching signal Sa1 is output to the upper arm driver 16A, and a dead time is set in which both the switching signals Sa1 and Sa2 are OFF. The upper and lower arm signal generator 23 is adjusted in advance so as to obtain a predetermined dead time length. The upper and lower arm signal generation unit 23 similarly processes the switching signal Sb2 applied to the lower arm driver 17B whose duty is corrected by the switching signal correction unit 22, and the switching signal Sb2 applied to the lower arm driver 17B and the upper arm driver. The switching signal Sb1 given to 16B is output. The upper and lower arm signal generation unit 23 is adjusted in advance so that the phase difference setting of the switching signals Sa2 and Sb2 whose duty is corrected by the switching signal correction unit 22 does not change. As described above, the upper and lower arm signal generation unit 23 generates the four switching signals Sa1, Sa2, Sb1, and Sb2 from the two switching signals Sa2 and Sb2 that have been subjected to duty correction by the switching signal correction unit 22.

  The switching signals Sa1, Sa2, Sb1, and Sb2 generated by the upper and lower arm signal generator 23 are input to the drivers 16A, 17A, 16B, and 17B of the chopper devices 100A and 100B, respectively, and the chopper devices 100A and 100B are input. Performs DC conversion.

  As described above, the bidirectional multiple chopper device according to the third embodiment has a dead time, and even when the switching elements 6A and 7A and the switching elements 6B and 7B of the upper and lower arms are turned on and off, the chopper device 100A, While reducing the current unbalance between 100B, the delay of the control which reduces a current unbalance state can be made small. Furthermore, the switching signal generation by the PWM method, the control for changing the on / off time of the switching signal to reduce the current imbalance, and the dead time of a predetermined length between the switching signals to the switching elements of the upper and lower arms Since the setting is performed independently, the overall influence due to the design change is small, and extra labor and labor can be reduced. For example, even if the control design for changing the ON / OFF time of the switching signal to reduce the current imbalance is changed, the influence on the accuracy of setting the predetermined dead time length is small.

  In the description of the multiple chopper device in FIG. 14, the switching signal generation unit 21 generates the switching signals Sa2 * and Sb2 * related to the drivers 17A and 17B of the switching elements 7A and 7B of the lower arms of the chopper devices 100A and 100B. However, the present invention is not limited to this, and the switching signals Sa1 * and Sb * 1 related to the drivers 16A and 16B of the switching elements 6A and 6B of the upper arms of the chopper devices 100A and 100B may be generated.

  In this case, the upper and lower arm signal generation unit 23 receives the switching signals Sa1 and Sb1 corrected by the switching signal correction unit 22 and provides a switching time Sa1 to the switching elements 6A and 6B of the upper arm with a dead time. A set of switching signals Sa2 and Sb2 to Sb1 and lower arm switching elements 7A and 7B is generated.

  The multi-chopper device shown in FIG. 14 is a bi-directional multi-chopper device that converts DC power through bidirectional flow between the low-voltage side battery 1 and the high-voltage side load 2. Unidirectional flow type switching elements 6A, 7A, 6B, 7B such as IGBTs are used, but not limited to this, a synchronous rectification type multiple chopper device that performs synchronous rectification using a bidirectional flow switch It is also possible to apply to.

FIG. 15 is a circuit diagram of the synchronous rectification type multiple chopper device.
The basic configuration of the multiple chopper device of FIG. 15 is the same as that shown in FIG. 14, but an ON command signal is input to the gate driver in the switching elements 6A, 7A, 6B, and 7B, like a MOSFET. In addition, a bidirectional flow switch is employed that can pass current with low resistance not only in the forward direction but also in the reverse direction of the switching element.

In the synchronous rectification type multiple chopper device shown in FIG. 15, during the period in which the return current flows through each diode 8A, 9A, 8B, 9B, the bidirectional communication connected in parallel to each diode 8A, 9A, 8B, 9B. Each switching element 6A, 7A, 6B, 7B which is a flow switch is turned on. Compared to the case where the return current is shunted through the diodes 8A, 9A, 8B, and 9B and the switching elements 6A, 7A, 6B, and 7B, and all the return current is passed through the diodes 8A, 9A, 8B, and 9B alone. The voltage drop of the reflux current is reduced. As described above, when a known synchronous rectification technique is used, the entire conduction loss can be reduced in the multiple chopper device that performs boosting, the multiple chopper device that performs step-down, and the multiple chopper device that performs boosting and step-down in both directions. .
Other configurations and operations are the same as those in the configuration shown in FIG. 14, and thus detailed description thereof is omitted here.

  14 and 15 according to the third embodiment, various modifications similar to those of the second to eighth modifications pointed out in the first embodiment can be applied. It is.

Embodiment 4 FIG.
FIG. 16 is a circuit diagram showing a multiple chopper device according to the fourth embodiment of the present invention. Components corresponding to or corresponding to those of the first embodiment shown in FIG.

  The multiple chopper device according to the fourth embodiment is a step-up type triple chopper device that boosts voltage from the low-voltage side battery 1 to the high-voltage side load 2, and three chopper devices 100 </ b> A between the battery 1 and the load 2. , 100B, 100C are connected in parallel. The multiple chopper device according to the fourth embodiment includes two current detectors 12AB and 12BC, two current waveform processing units 13AB and 13BC, and a control unit 20 that drives and controls the chopper devices 100A, 100B, and 100C. ing.

  As in the case of the first embodiment shown in FIG. 1, the first chopper device 100A includes a reactor 5A, an upper arm diode 8A, a lower arm diode 9A and a switching element 7A, and a driver 17A for driving the switching element 7A. Is provided. The second chopper device 100B includes a reactor 5B, an upper arm diode 8B, a lower arm diode 9B and a switching element 7B, and a driver 17B that drives the switching element 7B. The third chopper device 100C includes a reactor 5C, an upper arm diode 8C, a lower arm diode 9C and a switching element 7C, and a driver 17C for driving the switching element 7C.

  The control unit 20 outputs switching signals Sa, Sb, and Sc for commanding on / off of the switching elements 7A, 7B, and 7C to the drivers 17A, 17B, and 17C, and the chopper devices 100A, 100B, and 100C are zero and 2π, respectively. Driven at a phase of / 3, 4π / 3.

  In the fourth embodiment, a pair of wirings are selected by selecting each of the reactors 5A and 5B as the same wiring parts of the chopper devices 100A and 100B and superimposing them so that the directions of the currents flowing out from the respective wirings are reversed. A wire bundle 11AB is formed, and a current detector 12AB is installed at the location of the wire bundle 11AB. One current waveform processing unit 13AB includes a low-pass filter 131AB, extracts a DC component from a detected current Id1 indicating a current difference flowing through the wiring of the reactors 5A and 5B detected by the current detector 12AB, and outputs a current deviation signal. ΔI1 is output.

Further, as the same wiring parts of the chopper devices 100B and 100C, the respective wires of the reactors 5B and 5C are selected and superposed so that the directions of the currents flowing out from the respective wires are opposite to each other, so that the wire bundle 11BC composed of a pair of wires. And a current detector 12BC is installed at the location of the wiring bundle 11BC. The other current waveform processing unit 13BC includes a low-pass filter 131BC, extracts a DC component from a detected current Id2 indicating a current difference flowing through the wires of the reactors 5B and 5C detected by the current detector 12BC, and outputs a current deviation signal. ΔI2 is output.
Thus, the current deviation signals ΔI1 and ΔI2 generated by the current waveform processing units 13AB and 13BC are both input to the control unit 20.

  Here, the direct current component of the current flowing through the reactor 5A of the chopper device 100A is Ia, the direct current component of the current flowing through the reactor 5B of the chopper device 100B is Ib, and the direct current component Ic of the current flowing through the reactor 5C of the chopper device 100C is, for example, Ia The function of the control unit 20 will be described below taking as an example the case of = 16 amps, Ib = 11 amps, and Ic = 12 amps.

  The switching signal generation unit 21 sets the switching period and the phase difference between the parallel chopper devices, and outputs the switching signals Sa *, Sb *, and Sc * related to the drivers 17A, 17B, and 17C based on the input / output voltage settings. Generate each.

  The switching signal correction unit 22 receives the information that the reactor current of the chopper device 100A is higher by Ia−Ib = 5 amps than the reactor current of the chopper device 100B by inputting the current deviation signal ΔI1 generated by the current waveform processing unit 13AB. obtain. Further, the switching signal correction unit 22 inputs the current deviation signal ΔI2 generated by the current waveform processing unit 13BC, so that the reactor current of the chopper device 100C is Ic−Ib = 1 ampere higher than the reactor current of the chopper device 100B. get information. When the chopper devices 100A, 100B, and 100C are in a current balance state, the direct current components of the currents flowing through the reactors 5A, 5B, and 5C coincide with the average current (Ia + Ib + Ic) / 3 of Ia, Ib, and Ic.

In the fourth embodiment, the wires of the reactors 5A, 5B, and 5C are selected as the same wiring components of the chopper devices 100A, 100B, and 100C. Therefore, when the difference between the value of the current flowing through the reactor wiring and the average value of the current flowing through the reactor wiring is defined as the average current deviation for all the chopper devices, the average current deviation for all the chopper devices is expressed by the following formula ( 1).

  Based on the current deviation signals ΔI1 and ΔI2 generated by the current waveform processing units 13AB and 13BC based on the above formula (1), the switching signal correction unit 22 compares the average current of the chopper devices 100A, 100B, and 100C with each other. Calculate the deviation. In accordance with these calculated average current deviations, the switching signal correction unit 22 switches the switching signal Sa generated by the switching signal generation unit 21 so that the average current deviation is eliminated for all the chopper devices 100A, 100B, and 100C. *, Sb *, and Sc * are all subjected to duty correction.

  As for the above specific example, the switching signal correction unit 22 reduces the current flowing through the reactor 5A of the device 100A by 3 amperes with respect to the switching signal Sa * related to the chopper device 100A generated by the switching signal generation unit 21. Thus, the duty correction is performed on the switching signal Sb * related to the chopper device 100B so that the current flowing through the reactor 5B of the device 100B increases by 2 amperes, and the switching signal Sc related to the chopper device 100C. For *, the duty correction is performed so that the current flowing through the reactor 5C of the apparatus 100C increases by 1 ampere.

  In the configuration shown in FIG. 16, the switching signal correction unit 22 is configured to receive two current deviation signals ΔI1 and ΔI2. Further, although not illustrated, the reactors 5C and 5A of the chopper devices 100C and 100A are not shown. The wiring bundle 11CA is formed so that the direction of the current flowing out from each of the wirings is reversed, and the current detector 12CA is installed at the location of the wiring bundle 11CA, and separately from the current waveform processing units 13AB and 13BC. The current waveform processing unit 13CA having the configuration is provided, and a current deviation signal representing a current deviation between the chopper devices 100A and 100C by extracting a DC component from the detected current Id3 detected by the current detector 12CA by the current waveform processing unit 13CA. ΔI3 is generated, and in addition to the current deviation signals ΔI1 and ΔI2, the current deviation signal ΔI3 is switched on. It may be input to the signal correction unit 22.

  In this way, since the switching signal correction unit 22 inputs more current deviation signals ΔI1 to ΔI3, some current waveform processing units fail and some current deviation signals are interrupted. However, the average current deviation can be calculated from the remaining current deviation signal, which increases the reliability.

  Next, as described in the fourth embodiment, in the multiple chopper device having a multiplexing number of “3” or more, the switching signal correction unit 22 uses the concept of the above-mentioned average current deviation when reducing the current imbalance state. The advantages of performing duty correction will be described.

  Now, the switching signal correction unit 22 simply performs duty correction using only the current deviation signals ΔI1 and ΔI2 generated by the current waveform processing units 13AB and 13BC, and the average current deviation as in the fourth embodiment is corrected. Consider the case where duty correction using the concept is not performed.

  The switching signal correction unit 22 receives the current deviation signal ΔI1 generated by the current waveform processing unit 13AB, and the current flowing through the reactor 5A of the chopper device 100A is greater than the current flowing through the reactor 5B of the chopper device 100B, Ia−Ib = 5 amperes. Get high information. Therefore, the switching signal correction unit 22 reduces the current flowing through the reactor 5A of the chopper device 100A by 2.5 amperes with respect to the switching signal Sa * to the chopper device 100A generated by the switching signal generation unit 21. Make corrections. Further, the switching signal Sb * to the chopper device 100B generated by the switching signal generation unit 21 is tried to be corrected so that the current flowing through the reactor 5B of the chopper device 100B increases by 2.5 amperes.

  In addition, the switching signal correction unit 22 receives the current deviation signal ΔI2 generated by the current waveform processing unit 13BC, and the current flowing through the reactor 5C of the chopper device 100C is greater than the current flowing through the reactor 5B of the chopper device 100B by Ic−Ib = Get information that is one ampere higher. For this reason, the switching signal correction unit 22 increases the current flowing in the reactor 5B of the chopper device 100B by 0.5 amperes with respect to the switching signal Sb * to the chopper device 100B generated by the switching signal generation unit 21. Try to make corrections. Further, the switching signal Sc * to the chopper device 100C generated by the switching signal generation unit 21 is corrected so that the current flowing through the reactor 5C of the chopper device 100C is reduced by 0.5 amperes.

  As a result, the switching signal correction unit 22 has a current flowing through the reactor 5B of the chopper device 100B of 3 amperes (= 2.2) with respect to the switching signal Sb * to the chopper device 100B generated by the switching signal generation unit 21. 5 + 0.5) Correction that increases is performed. As described above, the current unbalance between the chopper devices 100A, 100B, and 100C is gradually reduced over time without fluctuation in the total output current to the load 2 of the chopper devices 100A, 100B, and 100C. It takes time for the balance to be reduced.

  That is, paying attention to the case of correcting the current imbalance with respect to the current flowing through the reactor 5C of the chopper device 100C, when the average current deviation based on the equation (1) is not calculated, the switching signal correction unit 22 The switching signal Sc * generated by the generation unit 21 is corrected so that the current flowing through the reactor 5C of the chopper device 100C is once reduced by 0.5 amperes. On the other hand, in the fourth embodiment, since the average current deviation is calculated, the switching signal correction unit 22 causes the current flowing through the reactor 5C of the chopper device 100C to be 1 at a time with respect to the switching signal Sc *. Make corrections to increase amperes. For this reason, the current unbalanced state between the chopper devices 100A, 100B, and 100C can be reduced in a short time without the total output current to the load 2 of the chopper devices 100A, 100B, and 100C changing.

  As described above, in the fourth embodiment, when the current unbalance state is reduced in the multiple chopper device having a multiplexing number of “3” or more, the switching signal correction unit 22 uses the concept of the above average current deviation. Since the duty correction is performed, the current imbalance between the chopper devices 100A, 100B, and 100C can be quickly reduced without changing the total output current to the loads of the chopper devices 100A, 100B, and 100C.

  The following various modifications can also be made to the configuration of the fourth embodiment shown in FIG.

  That is, various modifications similar to those of Modifications 2 to 7 pointed out in the first embodiment can be applied to the configuration shown in FIG. In the fourth embodiment, the multiplexing chopper device having a multiplexing number of “3” has been described. However, the present invention is not limited to this, and the present invention can be applied to a multiplexing chopper device having a multiplexing number of “4” or more. In the fourth embodiment of the present invention, the step-up type multiple chopper device that boosts DC power from the low-voltage side battery 1 to the high-voltage side load 2 has been described. The present invention can also be applied to a step-down chopper device that steps down DC power to a load on the low-voltage side. Furthermore, the present invention can also be applied to a bidirectional multiple chopper device that converts DC power by bidirectionally passing between the low voltage side and the high voltage side using the switching elements of the upper arm and the lower arm. The present invention can also be applied to a synchronous rectification multiple chopper device that performs synchronous rectification using a current switch.

100A, 100B, 100C Chopper device, 2 loads, 3 smoothing capacitors,
5A, 5B, 5C reactor,
6A, 6B, 6C switching element, 7A, 7B, 7C switching element,
8A, 8B, 8C diode, 9A, 9B, 9C diode,
11, 11AB, 11BC, 11CA wiring bundle,
12A, 12B, 12AB, 12BC, 12CA Current detector,
13, 13AB, 13BC, 13CA Current waveform processing unit,
16A, 16B, 17A, 17B, 17C driver, 20 control unit,
21 switching signal generation unit, 22 switching signal correction unit,
23 Upper and lower arm signal generator,
131, 131AB, 131BC low-pass filter, 132 calculator.

The multi-chopper device according to the present invention connects N chopper devices (N is an integer of 2 or more) in parallel with a reactor connected to the low-voltage side, a switching element connected to the reactor, and a diode, and each of the above-mentioned chopper devices. A multi-chopper device that performs DC conversion between the low-voltage side and the high-voltage side by turning on and off the switching elements of the chopper device with a phase difference between each other,
The arrangement position of the same wiring parts constituting each of the chopper device is provided with a current detector for detecting a difference between the current flowing through the same wiring part in sharing the DC conversion at each of the chopper device A switching signal generation unit that generates a switching signal for driving the device for each of the chopper devices, and a current waveform detected by the current detector to represent a current deviation between the chopper devices. A switching signal generated by the switching signal generator so as to reduce a current deviation between the chopper devices based on a current deviation signal generated by the current waveform processor generated by the current waveform processor generated by the current deviation signal And a switching signal correction unit for performing duty correction.

The multi-chopper device according to the present invention connects N chopper devices (N is an integer of 2 or more) in parallel with a reactor connected to the low-voltage side, a switching element connected to the reactor, and a diode, and each of the above-mentioned chopper devices. A multi-chopper device that performs DC conversion between the low-voltage side and the high-voltage side by turning on and off the switching elements of the chopper device with a phase difference between each other,
A current detector for detecting a difference in current flowing in the same wiring component when the DC conversion is shared by each of the chopper devices is provided at an arrangement position of the same wiring component constituting each of the chopper devices. A switching signal generation unit that generates a switching signal for driving the device for each of the chopper devices, and a current waveform detected by the current detector to represent a current deviation between the chopper devices. A switching signal generated by the switching signal generator so as to reduce a current deviation between the chopper devices based on a current deviation signal generated by the current waveform processor generated by the current waveform processor generated by the current deviation signal a switching signal correction unit that performs the duty correction, switching signal to the switching signal correction unit is subjected to duty correction Receiving and has and a driver for driving the switching element.

Claims (13)

N reactors connected to the low voltage side, switching devices connected to the reactor, and chopper devices composed of diodes are connected in parallel (N is an integer of 2 or more) in parallel, and the switching devices of the above chopper devices have a phase difference from each other. A multiple chopper device that performs direct current conversion between the low pressure side and the high pressure side by turning on and off.
In the location of the same wiring component constituting each of the chopper devices, a current detector for detecting a difference in current flowing in the same wiring component when sharing the DC conversion in each chopper device is provided,
A switching signal generator for generating a switching signal for driving the device for each of the chopper devices;
A current waveform processing unit that processes a current waveform detected by the current detector and generates a current deviation signal that represents a current deviation between the chopper devices;
A switching signal correction unit that corrects the switching signal generated by the switching signal generation unit so as to reduce the current deviation between the chopper devices based on the current deviation signal generated by the current waveform processing unit;
A multiple chopper device comprising: Each of the above chopper devices has an upper arm switching element and a lower arm switching element, and the switching elements belonging to the same arm are turned on with a dead time in which both the upper arm and lower arm switching elements are turned off. Switching off, the switching elements between the chopper devices are turned on and off with a phase difference between each other,
The switching signal generator generates a switching signal for each switching element of the upper arm and the lower arm of each chopper device,
The switching signal correction unit corrects each switching signal generated by the switching signal generation unit so that the current deviation between the chopper devices is reduced based on the current deviation signal generated by the current waveform processing unit. The multiple chopper device according to claim 1. Each of the above chopper devices has an upper arm switching element and a lower arm switching element, and the switching elements belonging to the same arm are turned on with a dead time in which both the upper arm and lower arm switching elements are turned off. Switching off, the switching elements between the chopper devices are turned on and off with a phase difference between each other,
The switching signal generation unit generates a switching signal for one of the switching elements of the upper arm and the lower arm of each chopper device,
The switching signal correction unit corrects each switching signal generated by the switching signal generation unit so that the current deviation between the chopper devices is reduced based on the current deviation signal generated by the current waveform processing unit. Yes,
Further, based on the switching signals corrected by the switching signal correction unit, the upper and lower arms generate a pair of two switching signals having a dead time in which the switching elements of the upper arm and the lower arm are both turned off. The multiple chopper device according to claim 1 provided with a signal generation part.   When two of the above chopper devices are combined into one set, the wiring components are overlapped so that the direction of the current flowing out from the same wiring component of each of the two chopper devices is opposite. A pair of wiring bundles are formed, and the current detector is arranged at a place where the wiring bundle is formed to detect a current difference between a pair of arranged parts flowing through the wiring bundle, and the current waveform processing unit 4. A low-pass filter that extracts a DC component from a current waveform detected by a detector and generates the current deviation signal representing a current deviation between a pair of chopper devices. The multiple chopper device according to item.   While selecting any one of the input wiring, the output wiring, the reactor, the switching element, and the diode that constitute each of the chopper devices as the same wiring component where the current deviation occurs, the wiring While each of the chopper devices is provided with the current detector that detects a current flowing through a component, the current waveform processing unit is configured to perform the above operation when two of the chopper devices are set as one set. An arithmetic unit that is provided corresponding to each set of chopper devices and extracts a current deviation between two sets of chopper devices, and calculates a difference between current waveforms detected by each of the current detectors. A low-pass filter that extracts a DC component from the outputs of the detector and the arithmetic unit, or a low-pass filter that extracts a DC component from the current waveform detected by each of the current detectors and the low-pass filter. Multiple chopper device according to any one of claims 1 to 3 comprising a calculator for calculating the difference between the DC component extracted by the pass filter.   The switching signal correction unit corrects a switching signal for one chopper device among the switching signals generated by the switching signal generation unit based on the current deviation signal generated by the current waveform processing unit. 6. The multiple chopper device according to claim 1, wherein correction is performed so that a current deviation among all the chopper devices is reduced with respect to the switching signals for the remaining chopper devices without performing the operation.   The switching signal correction unit reduces the current deviation between all the chopper devices based on the current deviation signal generated by the current waveform processing unit, and corrects the output current of all the chopper devices by correcting the switching signal. 6. The multiple chopper device according to claim 1, wherein correction is performed on all of the switching signals generated by the switching signal generation unit for the chopper devices so that the sum does not change.   The switching signal correction unit calculates a difference between the value of the current flowing through the wiring component and the average value of the current flowing through the wiring component for all chopper devices based on the current deviation signal generated by the current waveform processing unit. The multiplex according to claim 7, wherein the switching signal generation unit calculates all of the switching signals so as to eliminate the paired average current deviation for all chopper devices. Chopper device.   The multiple chopper device according to any one of claims 1 to 8, wherein the switching signal correction unit is configured to limit a correction amount when the switching signal generated by the switching signal generation unit is corrected. .   The multiple chopper device according to any one of claims 1 to 9, wherein the switching element is formed of a wide band gap semiconductor.   The multi-chopper device according to claim 10, wherein the wide band gap semiconductor is silicon carbide, a gallium nitride-based material, or diamond.   The multi-chopper device according to any one of claims 1 to 9, wherein the diode is formed of a wide band gap semiconductor.   The multi-chopper device according to claim 10, wherein the wide band gap semiconductor is silicon carbide, a gallium nitride-based material, or diamond.

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