Power conversion device

Abstract

The object of this invention is to reduce resonance between power modules even when switching timing deviations occur between multiple power modules connected in parallel. The power conversion device (90) of this invention includes a main circuit (91) with multiple power modules (1a, 1b) connected in parallel, and a drive circuit (92) driving the main circuit (91). The drive circuit (92) includes: a driver circuit (2) that generates control signals input to the respective control terminals (31a, 31b) of the multiple power modules (1a, 1b); and a filter (93) connected between the driver circuit (2) and the multiple control terminals (31a, 31b), and having a peak shape that increases impedance in a predetermined specific frequency band for each module group consisting of two modules (1a, 1b). The filter (93) has a coupling element (10) for each module group, which includes a capacitor (6) connected between two control terminals (31a, 31b).

Description

Technical Field

[0001] This application relates to power conversion devices. Background Technology

[0002] In recent years, power conversion devices used in electric powertrains such as hybrid vehicles and electric vehicles have increased power capacity by connecting multiple power modules with semiconductor switching elements such as IGBT (Insulated Gate Bipolar Transistor) and MOSFET (Metal Oxide Semiconductor Field Effect Transistor) in parallel and simultaneously switching and driving these power modules to perform processing (e.g., Patent Document 1).

[0003] The power conversion device in Patent Document 1 includes a gate drive circuit that simultaneously drives multiple power modules (semiconductor modules) connected in parallel, and a main circuit having multiple power modules connected in parallel. Like the power conversion device in Patent Document 1, in a power conversion device with multiple power modules connected in parallel, the timing of the switching actions of the power modules may sometimes differ due to differences in the characteristics of the semiconductor switching elements within the power modules, inductance deviations within the main circuit, and inductance deviations between the main circuit and the gate drive circuit.

[0004] When the switching timings of the power modules are different, current imbalance occurs between the power modules, for example, the current concentrates in the power module that turns on earliest. Therefore, if the current concentrates in one power module, the losses will increase, potentially exceeding the module's allowable limits. Furthermore, this current concentration problem, as described in Patent Document 2, can lead to resonance phenomena, for example, between two power modules connected in parallel.

[0005] The resonance phenomenon between power modules generates a voltage difference between them, caused by the inductance between the modules and the parasitic capacitance of the semiconductor switching elements within the modules. If the voltage amplitude caused by resonance overlaps with the surge peak voltage Vsp generated on the drain-source voltage Vds, the voltage applied between the drain and source, i.e., the drain-source voltage Vds, becomes larger, potentially exceeding the permissible limit of the power module. This is a particularly significant problem when switching is performed at high di / dt to reduce power module losses.

[0006] To address this resonance phenomenon, three methods can be considered, for example. The first method is to reduce the switching deviation between power modules. This requires reducing the deviation in component characteristics within the power modules and adjusting the trace lengths of the drain and source. The second method is to design with a low-speed di / dt instead of a high-speed di / dt, allowing for higher losses. In this case, if the power module losses increase, larger semiconductor switching elements and high-performance components are needed to accommodate this. The third method is to allow for resonance by selecting components with larger voltage ratings. In this case, such components generally have higher resistance during conduction, resulting in higher losses. Existing technical documents Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-156304 ( Figure 1 , Figure 4 ) Patent Document 2: Japanese Patent Application Publication No. 2021-44996 ( Figure 3 A, Figure 3 B) Summary of the Invention The technical problem that the invention aims to solve

[0008] In Patent Document 1, to eliminate current imbalance during the turn-off operation of multiple parallel-connected power modules, power modules with lower gate threshold voltages (i.e., slower turn-off) are connected to gate wiring with lower impedance, while power modules with higher gate threshold voltages (i.e., faster turn-off) are connected to gate wiring with higher impedance. Furthermore, to eliminate current imbalance during the turn-on operation of multiple parallel-connected power modules, power modules with lower gate threshold voltages (i.e., faster turn-on) are connected to gate wiring with higher impedance, while power modules with higher gate threshold voltages (i.e., slower turn-on) are connected to gate wiring with lower impedance. For this purpose, each power module has a conducting gate wiring with a diode and a turn-off gate wiring with a diode. To switch between the conducting gate wiring and the turn-off gate wiring, the diodes between the conducting gate wiring and the power module are oriented in opposite directions to those between the turn-off gate wiring and the power module. Thus, the power conversion device of Patent Document 1 can reduce current imbalance among multiple parallel-connected power modules.

[0009] If the current imbalance suppression method of the power conversion device in Patent Document 1 is adopted, the switching timing deviation between power modules can be reduced, thus preventing resonance between power modules. However, the characteristics of the power modules need to be selected to ensure consistent switching timing between them, and the gate wiring must be installed in the power conversion device in a way that matches the characteristics of the power modules, thereby complicating the manufacturing process of the power conversion device. Furthermore, the increased complexity of the manufacturing process leads to a deterioration in yield.

[0010] The purpose of the technology disclosed in this application is to reduce resonance between power modules even when switching timing deviations occur between multiple power modules connected in parallel. Technical means for solving technical problems

[0011] An example power conversion device disclosed in this application converts input power by controlling the conduction period of multiple main circuits having power modules, comprising: a main circuit with multiple power modules connected in parallel; and a drive circuit for driving the main circuit. The power modules include semiconductor switching elements. Two power modules are grouped together as a module group. The drive circuit includes a driver circuit that generates control signals input to the respective module control terminals of the multiple power modules. The drive circuit also includes a filter connected between the driver circuit and the multiple module control terminals, and has an impedance characteristic for each module group that results in a peak shape with increasing impedance in a pre-defined specific frequency band. The filter has a coupling element for each module group, the coupling element comprising a capacitor connected between the two module control terminals. Invention Effects

[0012] In one example of the power conversion device disclosed in this application, the drive circuit of the main drive circuit includes a filter that, for each module group, has a coupling element containing a capacitor connected between the control terminals of the two modules, thus reducing resonance between the power modules even if switching timing deviations occur between multiple power modules connected in parallel. Attached Figure Description

[0013] Figure 1 This is a diagram showing the structure of the first basic circuit of Embodiment 1. Figure 2 This is a diagram showing the structure of the power conversion device according to Embodiment 1. Figure 3 It is shown Figure 1 The diagram shows the equivalent circuit of the filter. Figure 4 It is shown Figure 1 The diagram shows the equivalent circuit of the filter. Figure 5 It is shown Figure 1 The diagram shows the equivalent circuit of the filter and the main circuit. Figure 6 It is shown Figure 5 The diagram of the resonant path loop. Figure 7 It is shown Figure 1 The diagram shows the equivalent circuit of the filter. Figure 8 It is shown Figure 1 The impedance characteristics of the filter are shown in the figure. Figure 9 This is a diagram showing an example of the output voltage of the main circuit in Embodiment 1. Figure 10 It is shown Figure 9 The diagram of the resonant components. Figure 11 This is a diagram showing an example of the output voltage of the main circuit in a comparative example. Figure 12 It is shown Figure 11 The diagram of the resonant components. Figure 13 It is shown Figure 1 A diagram showing an example of the configuration of resistors and coupling elements. Figure 14 This is a diagram showing the structure of the second basic circuit of Embodiment 1. Figure 15 This is a diagram showing the structure of the third basic circuit of Embodiment 1. Figure 16 It is shown Figure 15 The diagram shows the equivalent circuit of the filter. Figure 17 It is shown Figure 15 The diagram shows the equivalent circuit of the filter and the main circuit. Figure 18 This is a diagram showing the structure of the basic circuit involved in Embodiment 2. Figure 19 It is shown Figure 18 The diagram shows the equivalent circuit of the filter and the main circuit. Figure 20 This is a diagram illustrating an example of capacitor connection in Embodiment 1. Figure 21 This is a diagram illustrating an example of capacitor connection in Embodiment 2. Figure 22 This is a diagram illustrating another example of capacitor connection in Embodiment 2. Detailed Implementation

[0014] Implementation method 1. Figure 1This is a diagram showing the structure of the first basic circuit according to Embodiment 1. Figure 2 This is a diagram showing the structure of the power conversion device according to Embodiment 1. Figure 3 , Figure 4 It is shown Figure 1 The diagram shows the equivalent circuit of the filter. Figure 5 It is shown Figure 1 The equivalent circuit diagram of the filter and the main circuit. Figure 6 It is shown Figure 5 The diagram of the resonant path loop. Figure 7 , Figure 8 It is shown Figure 1 The impedance characteristics of the filter are shown in the figure. Figure 9 This is a diagram showing an example of the output voltage of the main circuit in Embodiment 1. Figure 10 It is shown Figure 9 The diagram of the resonant components. Figure 11 This is a diagram showing an example of the output voltage of the main circuit in the comparative example. Figure 12 It is shown Figure 11 The diagram of the resonant components. Figure 13 It is shown Figure 1 A diagram showing an example of the configuration of resistors and coupling elements. Figure 14 This is a diagram showing the structure of the second basic circuit according to Embodiment 1. Figure 15 This is a diagram showing the structure of the third basic circuit involved in Embodiment 1. Figure 16 It is shown Figure 15 The equivalent circuit diagram of the filter is shown. Figure 17 It is shown Figure 15 The diagram shows the equivalent circuit of the filter and the main circuit. Figure 2 An example of a power conversion device 90 is shown in the figure. Figure 1 The diagram shows the basic circuit 94 of a power conversion device 90. The power conversion device 90 performs power conversion on input power by controlling the conduction periods of multiple main circuits 91a, 91b, 91c, and 91d, each having multiple power modules 1a and 1b. The power conversion device 90 is, for example, a single-phase inverter comprising four basic circuits 94a, 94b, 94c, and 94d. Each of the basic circuits 94a, 94b, 94c, and 94d is configured as follows: Figure 1 The basic circuit 94 shown is illustrated.

[0015] Figure 2The power conversion device 90 shown converts the input power (DC) from the DC circuit 81 into AC power and outputs the converted AC power to the AC circuit 82. The power conversion device 90 controls the conduction periods of the main circuits 91a, 91b, 91c, and 91d of each basic circuit 94a, 94b, 94c, and 94d based on the drive circuit control signal sig1 output by the control circuit 83. Basic circuit 94a includes main circuit 91a and drive circuit 92a that drives main circuit 91a based on drive circuit control signal sig1. Similarly, basic circuits 94b, 94c, and 94d include main circuits 91b, 91c, and 91d, and drive circuits 92b, 92c, and 92d that drive main circuits 91b, 91c, and 91d based on drive circuit control signal sig1. The main circuits are uniformly labeled 91, but 91a, 91b, 91c, and 91d are used for distinction. The drive circuits are uniformly labeled with 92, and distinguished by 92a, 92b, 92c, and 92d. The basic circuits are uniformly labeled with 94, and distinguished by 94a, 94b, 94c, and 94d. Furthermore, the drive circuit control signal sig1 input to each drive circuit 92a, 92b, 92c, and 92d is an independent signal corresponding to the operation of the power conversion device 90, but... Figure 2 The Chinese version uniformly records sig1.

[0016] In the main circuit 91, multiple power modules 1a and 1b are connected in parallel. Power modules 1a and 1b include transistors Tr as semiconductor switching elements. Power modules 1a and 1b each have a transistor Tr as a MOSFET and a diode Di connected in reverse parallel to the source s and drain d of transistor Tr. The gates g of the two transistors Tr, which serve as control terminals, are connected to module control terminals 31a and 31b, respectively. The drains d of the two transistors Tr are connected to the first power terminals 32a and 32b of the module, respectively. The sources s of the two transistors Tr are connected to the second power terminals 33a and 33b of the module, respectively. The first power terminals 32a and 32b are terminals through which a power greater than the control signal input to the module control terminals 31a and 31b flows, and the second power terminals 33a and 33b are terminals that generate a potential as a voltage reference for the control signal.

[0017] Power module 1a's first power terminal 32a is connected to the main circuit's first power terminal 34 of the main circuit 91, and power module 1b's first power terminal 32b is connected to the main circuit's first power terminal 34 of the main circuit 91 via inductor 4. Inductor 4 is the inductance of the wiring connecting the first power terminals 32a and 32b. Power module 1a's second power terminal 33a and power module 1b's second power terminal 33b are connected to the main circuit's second power terminal 35 of the main circuit 91 via reference wiring 14. Reference wiring 14 is connected to the driver circuit 2's reference terminal 42 via the driver circuit 92's reference terminal 38. Power module 1a's control terminal 31a is connected to the driver circuit 92's control terminal 36a, and power module 1b's control terminal 31b is connected to the driver circuit 92's control terminal 36b. Power module 1a is turned on and off according to the control signal output from the driver circuit 92's control terminal 36a, thereby controlling the on-time of power module 1a. The power module 1b is turned on and off according to the control signal output from the control terminal 36b of the drive circuit 92, thereby controlling the on-time of the power module 1b.

[0018] Main circuits 91a, 91b, 91c, and 91d constitute a full-bridge circuit. Main circuits 91a and 91c are located on the upper arm side, and main circuits 91b and 91d are located on the lower arm side. The main circuits on the upper arm side and the lower arm side are connected in series. Specifically, the second power terminal 35 of the main circuit 91a and the first power terminal 34 of the main circuit 91b are connected in series, thus forming a series circuit. The second power terminal 35 of the main circuit 91c and the first power terminal 34 of the main circuit 91d are connected in series, thus forming a series circuit. The first power terminal 34 of the main circuits 91a and 91c is connected to the high-potential side bus 86p connected to the DC terminal 84p, and the second power terminal 35 of the main circuits 91b and 91d is connected to the low-potential side bus 86s connected to the DC terminal 84s. The DC terminal 84p is connected to the high-potential side of the DC circuit 81, and the DC terminal 84s is connected to the low-potential side of the DC circuit 81. Connection point n1 between main circuits 91a and 91b is connected to AC terminal 85a, and connection point n2 between main circuits 91c and 91d is connected to AC terminal 85b. AC power is output from AC wiring 87a connected to AC terminal 85a and AC wiring 87b connected to AC terminal 85b to AC circuit 82.

[0019] The drive circuit 92 includes: a driver circuit 2 that generates control signals input to the respective module control terminals 31a, 31b of the plurality of power modules 1a, 1b; and a filter 93 connected between the driver circuit 2 and the plurality of module control terminals 31a, 31b, and having impedance characteristics 22, 23 for each module group, the impedance characteristics 22, 23 having a peak shape of increased impedance in a pre-set specific frequency band. A module group is a group of two power modules among the plurality of power modules. Furthermore, in Embodiment 1, the number of module groups is one. Embodiment 2 will describe an example with three or more module groups.

[0020] The filter 93 includes: control signal wirings 11a and 11b for transmitting control signals from the output terminal 41 of the driver circuit 2 to the module control terminals 31a and 31b of each power module 1a and 1b; and a coupling element 10 comprising a capacitor 6 connected between the module control terminals 31a and 31b. The control signal wirings 11a and 11b are connected at connection point N1, which is a driver-side connection point on the output terminal 41 side of the driver circuit 2. The coupling element 10 is connected at connection points N2 and N3 on the module control terminals 31a and 31b side of the control signal wirings 11a and 11b. An inductance 5a is present in the control signal wiring 11a, and an inductance 5b is present in the control signal wiring 11b. One end of the capacitor 6 is connected to the control signal wiring 11a at connection point N2 via capacitor wiring 13a, and the other end of the capacitor 6 is connected to the control signal wiring 11b at connection point N3 via capacitor wiring 13b. Typically, the inductance 7a of the wiring is present in the capacitor wiring 13a, and the inductance 7b of the wiring is present in the capacitor wiring 13b. In the coupling element 10, the inductance 7a, the capacitor 6, and the inductance 7b are connected in series. Figure 1 The diagram shows a single driver circuit 2, with resistor 3a connected to control signal wiring 11a and resistor 3b connected to control signal wiring 11b in a first basic circuit 94. Control signals output from the output terminal 41 of the driver circuit 2 are input to the module control terminal 31a of the power module 1a via control signal wiring 11a and control terminal 36a. Control signals output from the output terminal 41 of the driver circuit 2 are input to the module control terminal 31b of the power module 1b via control signal wiring 11b and control terminal 36b.

[0021] exist Figure 1In the first basic circuit 94 shown, multiple power modules 1a and 1b connected in parallel share a single driver circuit 2, instead of each having an independent driver circuit 2. Therefore, the control signals, i.e., the on / off signals, between the driver circuits 2 when two driver circuits exist independently will not deviate, thereby reducing switching timing deviation. Since the first basic circuit 94 only requires one driver circuit 2, the number of components can be reduced, thus lowering costs. Figure 15 As shown, multiple power modules 1a and 1b connected in parallel can each include independent driver circuits 2a and 2b. Even if a switching timing deviation occurs between driver circuit 2a and driver circuit 2b, the resonance between power modules 1a and 1b can be reduced by filter 93. Figure 15 The drive circuit 92 in the third basic circuit 94 shown includes two driver circuits 2a and 2b and a filter 93. A control signal output from the output terminal 41a of driver circuit 2a is input to the module control terminal 31a of power module 1a via control signal wiring 11a and control terminal 36a. A control signal output from the output terminal 41b of driver circuit 2b is input to the module control terminal 31b of power module 1b via control signal wiring 11b and control terminal 36b. Reference wiring 14 is connected to the reference terminal 42a of driver circuit 2a and the reference terminal 42b of driver circuit 2b via the reference terminal 38 of drive circuit 92.

[0022] like Figure 3 As shown in the equivalent circuit, filter 93 has an LC parallel circuit consisting of a series inductor 27 and a coupling element 10. The series inductor 27 is obtained by connecting in series with inductor 5b via connection point N1 through inductor 5a. Filter 93 has an LC parallel circuit between the module control terminal 31a of power module 1a and the module control terminal 31b of power module 1b, and has an impedance characteristic 22 or impedance characteristic 23, which has a peak shape in which the impedance increases in a predetermined specific frequency band. Figure 7 The impedance characteristic shown in 22 is for the case where inductors 7a and 7b are at 0H. Figure 4 The equivalent circuit shown is as follows. Figure 8 The impedance characteristic shown in 23 is for the case where inductances 7a and 7b are greater than 0H. Figure 3 The equivalent circuit shown is as follows. Figure 3 In the equivalent circuit shown, the coupling element 10 has the structure of an LC series circuit. Figure 7 , Figure 8 In the diagram, the horizontal axis represents frequency [MHz], and the vertical axis represents impedance [au (any unit)].

[0023] like Figure 7As shown, impedance characteristic 22 is the characteristic that the impedance has a peak value at a specific frequency; that is, impedance characteristic 22 has a peak shape in which the impedance increases at the peak frequency fp. The specific frequency band including the peak frequency fp is, for example, a frequency band with an impedance more than 10 times that of the minimum impedance Z1 located at a lower frequency side than the peak frequency fp. The voltage amplitude component of the specific frequency band in the control signal attenuates as it propagates between power modules 1a and 1b through the control signal wiring 11a and 11b.

[0024] The method for setting the peak frequency fp is explained. Figure 5 The equivalent circuit is shown when a voltage difference is generated in the inputs of power modules 1a and 1b due to the switching timing deviation between them. Figure 5 In the filter 93, a main circuit impedance 28 is formed between module control terminals 31a and 31b, serving as the impedance of the main circuit 91. The main circuit impedance 28 is formed by connecting in series a first module capacitor Cdg1 between the first power terminal 32a and module control terminal 31a in one power module 1a, an inductor 4a between the first power terminal 32a of one power module 1a and the first power terminal 32b of another power module 1b, and a second module capacitor Cdg2 between the first power terminal 32b and module control terminal 31b in another power module 1b. In the filter 93, within ±25% of the resonant frequency fc of the loop path 29 formed by the two control signal wirings 11a and 11b including the series inductor 27 and the main circuit impedance 28, the peak frequency fp at which the impedance in the impedance characteristics 22 and 23 of the LC parallel circuit composed of the series inductor 27 and the coupling element 10 reaches its peak value is set.

[0025] use Figures 9-12 This illustrates that even if switching timing deviations occur between multiple power modules connected in parallel, resonance between the power modules can be reduced. Figure 9 It shows the result from Figure 1 The example shown illustrates the output voltage of the main circuit 91 driven by the control signal output from the drive circuit 92. The drive circuit in the comparative example is... Figure 1 The driving circuit 92 is not connected to the coupling element 10. The main circuit of the comparative example is the same as the main circuit 91. Figure 9 , Figure 11 The output voltages of the main circuit 91 in Embodiment 1 and the main circuit 91 in the Comparative Example are respectively represented. Figure 10 This illustrates the resonant component in the output voltage of the main circuit 91 in Embodiment 1. Figure 12 The resonant component in the output voltage of the main circuit 91 of the comparative example is shown. Figures 9-12 The horizontal axis represents time. Figure 9 , Figure 11The vertical axis represents the drain-source voltage Vds, which is the output voltage. Figure 10 , Figure 12 The vertical axis represents the resonant component of the drain-source voltage Vds, which is the output voltage. Figure 9 , Figure 11 The times t0, t1, t2, t3, t4, t5, t6, and t7 recorded in the data are respectively related to... Figure 10 , Figure 12 The times recorded in the data are the same as t0, t1, t2, t3, t4, t5, t6, and t7.

[0026] First, let's explain the comparative example. In the case where there is a timing deviation in the switching between power modules 1a and 1b, such as... Figure 11 and Figure 12 As shown, resonance occurs between power modules 1a and 1b. Voltage characteristic 51a is the voltage characteristic of the first power module 1a when it is turned off. Voltage characteristic 51b is the voltage characteristic of the second power module 1b when it is turned off after a delay deviation time ΔTs. Vdc is the bus voltage of the power conversion device, Vsp is the surge peak voltage, and ΔVp is the superimposed peak voltage on the surge peak voltage Vsp. Voltage characteristic 52 is the resonant component in voltage characteristic 51a. Figure 11 The maximum peak voltage Vb in voltage characteristic 51a is shown in the figure. Figure 12 The diagram shows the oscillation voltage Vrb corresponding to the resonant component of the peak voltage Vb. Although Figure 11 The voltage characteristics 51a and 51b are shown when the power module is turned off, but resonance also occurs when the power module is turned on.

[0027] The output voltage and its resonant component of the main circuit 91 in Embodiment 1 will be explained. Voltage characteristic 51a is the voltage characteristic of the first power module 1a when it is turned off. Voltage characteristic 53b is the voltage characteristic of the second power module 1b when it is turned off with a delay deviation time ΔTs. Voltage characteristic 54 is the resonant component in voltage characteristic 53a. For voltage characteristic 53a in Embodiment 1, the peak voltage Vb of the comparative example is reduced to peak voltage Va. For voltage characteristic 54 in Embodiment 1, the vibration voltage Vrb of the comparative example is reduced to vibration voltage Vra.

[0028] In the power conversion device 90 of Embodiment 1, since the filter 93 of the basic circuit 94 has impedance characteristics 22 and 23 with the peak frequency fp set within ±25% of the resonant frequency fc of the loop path 29, it can suppress resonance between power modules 1a and 1b, and suppress resonance such as... Figure 11As shown, the resonant amplitude between power modules 1a and 1b is superimposed on the voltage surge between the first power terminal 32a and the second power terminal 33a of power module 1a, or between the first power terminal 32b and the second power terminal 33b of power module 1b. Therefore, the power conversion device 90 of Embodiment 1 can reduce the peak voltages between the first power terminal 32a and the second power terminal 33a, and between the first power terminal 32b and the second power terminal 33b in the main circuit 91. The drain-source voltage Vds is the output voltage when the transistor Tr of power modules 1a and 1b is a MOSFET.

[0029] For the impedance characteristics 23 when inductors 7a and 7b have values ​​greater than 0H, since coupling element 10 adopts an LC series circuit structure, therefore... Figure 8 As shown, the impedance increases on the high-frequency side at the peak frequency fp, forming a frequency domain with lower impedance and exhibiting bandpass characteristics.

[0030] When the inductances 7a and 7b of capacitor wirings 13a and 13b have values ​​greater than 0H, the inductance values ​​of inductors 7a and 7b are less than half of the inductances 5a and 5b of control signal wirings 11a and 11b. That is, the coupling element 10 has inductances 7a and 7b between one end of a control signal wiring 11a and one end of capacitor 6, and between the other end of capacitor 6 and another control signal wiring 11b, and the values ​​of the inductances 7a and 7b of the coupling element 10 are less than half of the value of the series inductance 27. As a result, the filter 93 has a high impedance at the resonant frequency fc between power modules 1a and 1b, which can separate the bandpass characteristic frequency band from the resonant frequency fc between power modules 1a and 1b by tens of MHz or more, and can cut off the resonant frequency fc between power modules 1a and 1b to reduce the resonant amplitude.

[0031] To ensure that the inductance values ​​of capacitor wirings 13a and 13b (7a and 7b) are less than half of the inductance values ​​of control signal wirings 11a and 11b (5a and 5b), such as... Figure 13 As shown, the coupling element 10, including capacitor 6, can be mounted on the same substrate as the substrate 18 on which resistors 3a and 3b are mounted. Furthermore, the coupling element 10 can be a surface-mount capacitor 17 with a withstand voltage of tens to hundreds of V. When the coupling element 10 is capacitor 17, the inductors 7a and 7b can be 0H or lower than the capacitor wirings 13a and 13b. Figure 13 An example is shown where the driver circuit 2, coupling element 10, and resistors 3a and 3b are mounted on a substrate 18. Resistors 3a and 3b are, for example, surface mount resistors, i.e., chip resistors.

[0032] With resistors 3a and 3b connected to control signal wirings 11a and 11b, the drive circuit 92 has resistors 3a and 3b for each power module 1a and 1b, and outputs control signals to each power module 1a and 1b via resistors 3a and 3b. In this case, even if resonance occurs between the module control terminals 31a and 31b of the power modules 1a and 1b, it can be attenuated by resistors 3a and 3b, thus preventing malfunction. Even if the filter 93 fails, resistors 3a and 3b in the control signal wirings 11a and 11b can maintain their effect of preventing malfunction.

[0033] In the power conversion device 90 of Embodiment 1, since the drive circuit 92 for driving the main circuit 91 has a filter 93, which includes a coupling element 10 comprising a capacitor 6 connected between the two module control terminals 31a and 31b, resonance between the power modules 1a and 1b can be reduced even if switching timing deviations occur between the multiple power modules 1a and 1b connected in parallel. The power conversion device 90 of Embodiment 1 does not require the selection of high-voltage components with high resistance and high losses during conduction to address resonance phenomena, nor does it require a low-speed di / dt design instead of a high-speed di / dt design to allow for higher losses. The power conversion device 90 of Embodiment 1 does not require the use of expensive large-size semiconductor switching elements or costly high-performance components, thus avoiding the cost increases caused by conventional resonance countermeasures.

[0034] Additionally, the power conversion device 90 of Embodiment 1, as shown in the example... Figure 14 As shown in the second basic circuit 94, in addition to resistors 3a and 3b, resistor 39 can also be included in the semiconductor switching elements used in power modules 1a and 1b. Resistor 39 of power module 1a is connected between module control terminal 31a and the gate g of transistor Tr. Similarly, resistor 39 of power module 1b is connected between module control terminal 31b and the gate g of transistor Tr. Because power modules 1a and 1b include resistor 39 in this way, the degree of freedom in setting the values ​​of resistors 3a and 3b is increased, the impedance adjustment range of filter 93 is increased, and the design to match the intensity of the resonant amplitude between power modules 1a and 1b becomes easier.

[0035] Furthermore, when power modules 1a and 1b include resistors 39, resistors 3a and 3b can be simply wiring resistors, rather than being mounted using surface-mount resistors or the like. In this case, since power modules 1a and 1b include resistors 39, it not only prevents damage to power modules 1a and 1b from excessive switching speeds and surge-induced overvoltages, but also reduces the cost of the power conversion device 90 due to fewer mounting components on the substrate 18. Moreover, the reduced number of mounting components on the substrate 18 increases the flexibility in component layout, allowing the filter 93 to be placed in a more appropriate location.

[0036] In basic circuit 94 Figure 15 In the case of the third basic circuit 94 shown, the equivalent circuit of filter 93 is as follows: Figure 16 As shown, the equivalent circuits of filter 93 and main circuit 91 when a voltage difference is generated at the input are as follows: Figure 17 As shown. The equivalent circuit of filter 93 in the third basic circuit 94, the filter 93 under the condition of generating a voltage difference in the input, and the equivalent circuit of main circuit 91 are respectively compared with... Figure 3 , Figure 5 The difference in the equivalent circuit shown is that inductors 5a and 5b are not directly connected. However, since driver circuits 2a and 2b operate through the same driver control signal sig1, even if there is a slight timing deviation between driver circuits 2a and 2b, output terminals 41a and 41b can be considered virtually connected. Therefore, the third basic circuit 94 operates in the same way as the first basic circuit 94. In other words, the filter 93 of the third basic circuit 94 operates in the same way as the filter 93 of the first basic circuit 94.

[0037] The semiconductor switching elements of power modules 1a and 1b are not limited to silicon MOSFETs, but can also be IGBTs. When the semiconductor switching elements of power modules 1a and 1b are IGBTs, the voltage between the first power terminals 32a and 32b and the second power terminals 33a and 33b, i.e., the output voltage, is the collector-emitter voltage. Furthermore, the semiconductor switching elements can be MOSFETs or IGBTs using wide-bandgap semiconductor materials. Power semiconductor switching elements using wide-bandgap semiconductor materials have high withstand voltage, good heat dissipation, and can perform high-speed switching. Semiconductor switching elements using wide-bandgap semiconductor materials include, for example, those using SiC (silicon carbide), GaN (gallium nitride), or diamond-based materials as substrates. Using wide-bandgap semiconductor switching elements can increase switching speed and reduce switching losses. The switching speed of the main circuit 91, including power modules 1a and 1b, i.e., the combined switching speed of power modules 1a and 1b, can be set to a maximum conceivable value that includes the overcurrent protection region and other normal operating range of the main circuit 91, at least 50 kA / μs. Power modules 1a and 1b have semiconductor switching elements using wide-bandgap semiconductor materials. In particular, during high-speed di / dt operation at 50 kA / μs or higher, resonance between power modules 1a and 1b is significant without the filter 93. However, since the power conversion device 90 of Embodiment 1 includes the filter 93, the switching speed of the main circuit 91 is 50 kA / μs or higher, reducing resonance between power modules 1a and 1b even when switching timing deviations occur between multiple power modules 1a and 1b connected in parallel.

[0038] As described above, the power conversion device 90 of Embodiment 1 is a power conversion device that controls the conduction period of multiple main circuits 91 (91a, 91b, 91c, 91d) having power modules 1a and 1b to convert input power. It includes a main circuit 91 having multiple power modules 1a and 1b connected in parallel, and a drive circuit 92 driving the main circuit 91. Power modules 1a and 1b include semiconductor switching elements (transistors Tr). Two power modules 1a and 1b are configured as a module group. The drive circuit 92 includes a driver circuit 2 that generates control signals input to the respective module control terminals 31a and 31b of the multiple power modules 1a and 1b. It also includes a filter 93 connected between the driver circuit 2 and the multiple module control terminals 31a and 31b, and has impedance characteristics 22 and 23 for each module group, the impedance characteristics 22 and 23 having a peak shape where impedance increases in a predetermined specific frequency band. The filter 93 has a coupling element 10 for each module group, which includes a capacitor 6 connected between the two module control terminals 31a, 31b. In the power conversion device 90 of Embodiment 1, according to this structure, since the drive circuit 92 for driving the main circuit 91 has a filter 93, which has a coupling element 10 for each module group, and the coupling element 10 includes a capacitor 6 connected between the two module control terminals 31a, 31b, the resonance between the power modules 1a, 1b can be reduced even if switching timing deviations occur between the multiple power modules 1a, 1b connected in parallel.

[0039] Implementation method 2. Figure 18 This is a diagram showing the structure of the basic circuit of Embodiment 2. Figure 19 It is shown Figure 18 The diagram shows the equivalent circuit of the filter and main circuit. Figure 20 This is a diagram showing an example of capacitor connection in Embodiment 1. Figure 21 This is a diagram showing an example of capacitor connection in Embodiment 2. Figure 22 This diagram illustrates another example of capacitor connection in Embodiment 2. The power conversion device 90 of Embodiment 2 differs from the power conversion device 90 of Embodiment 1 in that the main circuit 91 of the basic circuit 94 has three or more power modules. Hereinafter, the description will focus on the parts that differ from Embodiment 1.

[0040] Figure 18 The basic circuit 94 shown is an example of a main circuit 91 including three power modules 1a, 1b, and 1c. Figure 18In the example, the number of module groups is 3. The first module group is a group of power modules 1a and 1b. The second module group is a group of power modules 1b and 1c, and the third module group is a group of power modules 1a and 1c. Filter 93 has impedance characteristics 22 and 23 for each module group, which have a peak shape in which the impedance increases in a pre-defined specific frequency band.

[0041] In the main circuit 91, multiple power modules 1a, 1b, and 1c are connected in parallel. The gates g of the three transistors Tr, which serve as control terminals, are connected to the module control terminals 31a, 31b, and 31c, respectively. The drains d of the three transistors Tr are connected to the first power terminals 32a, 32b, and 32c, respectively. The sources s of the three transistors Tr are connected to the second power terminals 33a, 33b, and 33c, respectively. The first power terminals 32a, 32b, and 32c are terminals through which power greater than the control signals input to the module control terminals 31a, 31b, and 31c flows, and the second power terminals 33a, 33b, and 33c are terminals that generate potentials that serve as voltage references for the control signals.

[0042] The first power terminal 32a of power module 1a is connected to the first power terminal 34 of the main circuit 91. The first power terminal 32b of power module 1b is connected to the first power terminal 34 of the main circuit 91 via inductor 4a. The first power terminal 32c of power module 1c is connected to the first power terminal 34 of the main circuit 91 via inductors 4a and 4b. Inductor 4a is the inductor of the wiring connecting the first power terminals 32a and 32b. Inductor 4b is the inductor of the wiring connecting the first power terminals 32b and 32c. The second power terminals 33a, 33b, and 33c of power module 1a, power module 1b, and power module 1c are connected to the second power terminal 35 of the main circuit 91 via reference wiring 14. Reference wiring 14 is connected to the reference terminal 42 of the driver circuit 2 via the reference terminal 38 of the driver circuit 92. Power module 1a's module control terminal 31a is connected to drive circuit 92's control terminal 36a, and power module 1b's module control terminal 31b is connected to drive circuit 92's control terminal 36b. Power module 1c's module control terminal 31c is connected to drive circuit 92's control terminal 36c. Power module 1a is turned on and off according to the control signal output from drive circuit 92's control terminal 36a, thereby controlling the on-time of power module 1a. Power module 1b is turned on and off according to the control signal output from drive circuit 92's control terminal 36b, thereby controlling the on-time of power module 1b. Power module 1c is turned on and off according to the control signal output from drive circuit 92's control terminal 36c, thereby controlling the on-time of power module 1c.

[0043] The drive circuit 92 includes: a driver circuit 2 that generates control signals input to the respective module control terminals 31a, 31b, 31c of the plurality of power modules 1a, 1b, 1c; and a filter 93 connected between the driver circuit 2 and the plurality of module control terminals 31a, 31b, 31c, and having impedance characteristics 22, 23 for each module group, the impedance characteristics 22, 23 having a peak shape of increased impedance in a pre-set specific frequency band.

[0044] Filter 93 includes coupling elements comprising control signal wirings 11a, 11b, 11c for transmitting control signals from the output terminal 41 of driver circuit 2 to the module control terminals 31a, 31b, 31c of the respective power modules 1a, 1b, 1c, and capacitors connected between the module control terminals 31a, 31b, 31c. It also includes coupling element 10a, which includes a capacitor 6a connected between the module control terminals 31a, 31b. Coupler 10b includes a capacitor 6b connected between the module control terminals 31b, 31c. Coupler 10c includes a capacitor 6c connected between the module control terminals 31a, 31c. Control signal wirings 11a, 11b, and 11c are connected at connection point N1, which is a driver-side connection point on the output terminal 41 side of driver circuit 2. Coupler 10a is connected at connection points N2 and N3 on the module control terminals 31a and 31b in control signal wiring 11a and 11b. Coupler 10b is connected at connection points N3 and N4 on the module control terminals 31b and 31c in control signal wiring 11b and 11c. Coupler 10c is connected at connection points N5 and N6 on the module control terminals 31a and 31c in control signal wiring 11a and 11c.

[0045] In control signal wirings 11a, 11b, and 11c, inductances 5a, 5b, and 5c are present, respectively. One end of capacitor 6a is connected to control signal wiring 11a at connection point N2 via capacitor wiring 13a, and the other end of capacitor 6a is connected to control signal wiring 11b at connection point N3 via capacitor wiring 13b. One end of capacitor 6b is connected to control signal wiring 11b at connection point N3 via capacitor wiring 13c, and the other end of capacitor 6b is connected to control signal wiring 11c at connection point N4 via capacitor wiring 13d. One end of capacitor 6c is connected to control signal wiring 11a at connection point N5 via capacitor wiring 13e, and the other end of capacitor 6c is connected to control signal wiring 11c at connection point N6 via capacitor wiring 13f. Generally, inductances 7a, 7b, 7c, 7d, 7e, and 7f are present in capacitor wirings 13a, 13b, 13c, 13d, 13e, and 13f, respectively. In coupling element 10a, inductor 7a, capacitor 6a, and inductor 7b are connected in series. In coupling element 10b, inductor 7c, capacitor 6b, and inductor 7d are connected in series. In coupling element 10c, inductor 7e, capacitor 6c, and inductor 7f are connected in series. Figure 18An example of a driver circuit 2 is shown, with resistors 3a, 3b, and 3c connected to control signal wirings 11a, 11b, and 11c, respectively.

[0046] The control signal output from the output terminal 41 of the driver circuit 2 is transmitted in control signal wirings 11a, 11b, and 11c. The control signal transmitted in control signal wiring 11a is input to the module control terminal 31a of the power module 1a via control terminal 36a. The control signal transmitted in control signal wiring 11b is input to the module control terminal 31b of the power module 1b via control terminal 36b, and the control signal transmitted in control signal wiring 11c is input to the module control terminal 31c of the power module 1c via control terminal 36c.

[0047] like Figure 19 As shown in the equivalent circuit when a voltage difference is generated at the input, filter 93 has an LC parallel circuit for each module group, consisting of a series inductor and a coupling element, in which the inductors for the two control signal wirings are connected in series. The LC parallel circuit for filter 93 corresponding to the first module group is a circuit where a series inductor and coupling element 10a are connected in parallel, in which inductor 5a and inductor 5b connected via connection point N1 are connected in series. The LC parallel circuit for filter 93 corresponding to the second module group is a circuit where a series inductor and coupling element 10b are connected in parallel, in which inductor 5b and inductor 5c connected via connection point N1 are connected in series. The LC parallel circuit for filter 93 corresponding to the third module group is a circuit where a series inductor and coupling element 10c are connected in parallel, in which inductor 5a and inductor 5c connected via connection point N1 are connected in series. Each module group's LC parallel circuit has an impedance characteristic 22 or an impedance characteristic 23, which has a peak shape of impedance increase in a predetermined specific frequency band as described in Embodiment 1.

[0048] The main circuit impedance 28 described in Implementation 1 is the impedance when a voltage difference is generated at the input due to the switching timing deviation between the power modules in a module group. Therefore, due to the loop path 29 in the module group that generates a voltage difference at the input (refer to...) Figure 6 The resonance phenomenon occurs in the LC parallel circuit containing the coupling elements of the corresponding module group, so the resonance between the power modules of the corresponding module group can be suppressed. Figure 19The diagram illustrates the main circuit impedances 28a, 28b, and 28c when a voltage difference arises in the inputs of power modules 1a and 1b due to a switching timing deviation between them; 28b and 28c when a voltage difference arises in the inputs of power modules 1b and 1c due to a switching timing deviation between them; and 28c when a voltage difference arises in the inputs of power modules 1a and 1c due to a switching timing deviation between them. When a voltage difference arises in the inputs of multiple power modules, resonance between the power modules in the corresponding module group can be suppressed by an LC parallel circuit including coupling elements for each corresponding module group. The main circuit impedances 28a, 28b, and 28c are the impedances between the control terminals of one module and another module in the module group of the main circuit 91, and therefore can also be referred to as module group impedances.

[0049] The main circuit impedance 28a when a voltage difference is generated between the inputs of the power modules in the first module group is obtained by connecting the first module capacitor Cdg1 between the first power terminal 32a and the module control terminal 31a in one power module 1a, the inductor 4a between the first power terminal 32a of one power module 1a and the first power terminal 32b of another power module 1b, and the second module capacitor Cdg2 between the first power terminal 32b and the module control terminal 31b in another power module 1b in series. Similarly, the main circuit impedance 28b when a voltage difference is generated between the inputs of the power modules in the second module group is obtained by connecting the second module capacitor Cdg2 between the first power terminal 32b and the module control terminal 31b in one power module 1b, the inductor 4b between the first power terminal 32b of one power module 1b and the first power terminal 32c of another power module 1c, and the third module capacitor Cdg3 between the first power terminal 32c and the module control terminal 31c in another power module 1c in series. The main circuit impedance 28c when a voltage difference is generated in the input between the power modules of the third module group is the impedance obtained by connecting the first module capacitor Cdg1 between the first power terminal 32a and the module control terminal 31a in one power module 1a, the inductors 4a and 4b between the first power terminal 32a of one power module 1a and the first power terminal 32c of another power module 1c, and the third module capacitor Cdg3 between the first power terminal 32c and the module control terminal 31c in another power module 1c in series.

[0050] In filter 93, the peak frequency fp of the impedance characteristics 22 and 23 of the LC parallel circuit corresponding to each module group is set within ±25% of the resonant frequency fc of the loop path corresponding to each module group. The loop path of the first module group is formed by two control signal wirings 11a and 11b and the main circuit impedance 28a, which include a series inductor with inductors 5a and 5b connected in series. The loop path of the second module group is formed by two control signal wirings 11b and 11c and the main circuit impedance 28b, which include a series inductor with inductors 5b and 5c connected in series. The loop path of the third module group is formed by two control signal wirings 11a and 11c and the main circuit impedance 28c, which include a series inductor with inductors 5a and 5c connected in series.

[0051] In the power conversion device 90 of Embodiment 2, the filter 93 of the basic circuit 94 has impedance characteristics 22 and 23. These impedance characteristics 22 and 23 have a peak frequency fp within ±25% of the resonant frequency fc of the loop path corresponding to each module group. Therefore, the resonance between the two power modules in each corresponding module group can be suppressed, and the voltage surge between the resonant amplitude of the two power modules can be suppressed from being superimposed on the first power terminal and the second power terminal of the power module. Therefore, the power conversion device 90 of Embodiment 2 can reduce the peak voltage between the first power terminals 32a, 32b, and 32c of the module and the second power terminals 33a, 33b, and 33c of the module in the main circuit 91.

[0052] Even when three or more power modules are connected in parallel to the main circuit 91 of the basic circuit 94, the power conversion device 90 of Embodiment 2 can suppress resonance that may occur between all power modules.

[0053] use Figure 18 and Figure 19 The basic circuit 94 is explained when the number of power modules connected in parallel is 3. Even if the number of power modules is 4 or more, a filter 93 with the same number of coupling elements 10 as the number of module groups can be constructed. Figures 20 to 22 The diagram shows an example of the connection between the power module and the capacitor 6 in the coupling element 10. Figure 20 The diagram shows an example of the connection between two power modules 1a and 1b corresponding to Embodiment 1 and the capacitor 6 in the coupling element 10. In the case of two power modules 1a and 1b, since the number of module groups is 1, there is one capacitor 6.

[0054] Figure 21 The diagram shows the implementation method 2. Figure 18 Example of connection between the three corresponding power modules 1a, 1b, and 1c and the capacitors 6a, 6b, and 6c in the coupling elements 10a, 10b, and 10c. In the case of three power modules 1a, 1b, and 1c, since the number of module groups is 3, there are 3 capacitors. Figure 22 An example connection of four power modules 1a, 1b, 1c, and 1d with capacitors 6a, 6b, 6c, 6d, 6e, and 6f in six coupling elements is shown. In the case of four power modules 1a, 1b, 1c, and 1d, since the number of module groups is six, there are six capacitors. The capacitors in the coupling elements are as follows... Figures 20 to 22 As shown, the number and connection method of the coupling elements 10, including capacitor 6, are as follows: the same number of coupling elements 10 as the number of module groups are connected to each module group. More specifically, based on the number of power modules connected in parallel, capacitors are connected in a complete diagram with the module control terminals of the power modules as vertices. Figure 21 In the diagram, the module control terminals 31a, 31b, and 31c of power modules 1a, 1b, and 1c are vertices of the complete graph. Figure 22 In the diagram, the module control terminals 31a, 31b, 31c, and 31d of power modules 1a, 1b, 1c, and 1d are vertices of the complete graph.

[0055] As described above, the power conversion device 90 of Embodiment 2 is a power conversion device that controls the conduction period of multiple main circuits 91 (91a, 91b, 91c, 91d) having power modules 1a, 1b, and 1c to convert input power. It includes the main circuits 91 connected in parallel with the multiple power modules 1a, 1b, and 1c, and a drive circuit 92 that drives the main circuits 91. The power modules 1a, 1b, and 1c include semiconductor switching elements (transistors Tr). Two power modules 1a, 1b (or 1a, 1c, or 1b, 1c) among the multiple power modules 1a, 1b, and 1c form a module group. The drive circuit 92 includes a driver circuit 2 that generates control signals input to the respective module control terminals 31a, 31b, 31c of the plurality of power modules 1a, 1b, 1c. It also includes a filter 93 connected between the driver circuit 2 and the plurality of module control terminals 31a, 31b, 31c, and having impedance characteristics 22, 23 for each module group, the impedance characteristics 22, 23 having a peak shape with increasing impedance in a pre-defined specific frequency band. For each module group, the filter 93 has coupling elements 10a, 10b, 10c, the coupling elements 10a, 10b, 10c including capacitors 6a, 6b, 6c connected between two module control terminals 31a, 31b, 31c. In the power conversion device 90 of Embodiment 2, according to this structure, the drive circuit 92 of the drive main circuit 91 includes a filter 93. For each module group, the filter 93 has coupling elements 10a, 10b, and 10c. The coupling elements 10a, 10b, and 10c include capacitors 6a, 6b, and 6c connected between two module control terminals 31a and 31b (or 31a and 31c, or 31b and 31c). Therefore, even if a switching timing deviation occurs between multiple power modules 1a, 1b, and 1c connected in parallel, the resonance between the power modules 1a, 1b, and 1c can be reduced.

[0056] Furthermore, as an example of the power conversion device 90, a single-phase inverter for converting DC to AC is described, but it is not limited to this. The power conversion device 90 can be a converter that converts AC to DC, a DC / DC converter that converts DC to DC, or an AC / AC converter that converts AC to AC. Additionally, the power conversion device 90 is not limited to single-phase and can also be a three-phase structure. Furthermore, when the drive circuit 92 and the main circuit 91 are mounted on the same substrate, the control terminals 36a, 36b, 36c, and reference terminal 38 of the drive circuit 92 may be omitted. In this case, the control signal wirings 11a, 11b, and 11c are directly connected to the corresponding module control terminals 31a, 31b, and 31c, and the reference wiring 14 is directly connected to the reference terminal 42 of the main circuit 91 and the driver circuit 2.

[0057] Furthermore, although this application describes various exemplary embodiments and examples, the various features, methods, and functions described in one or more embodiments are not limited to specific embodiments, but can also be applied individually or in various combinations to embodiments. Therefore, it can be considered that numerous modifications not illustrated are also included within the scope of the technology disclosed in this application. For example, this may include modifications, additions, or omissions of at least one structural element, as well as extraction of at least one structural element and combination with structural elements of other embodiments. Label Explanation

[0058] 1a, 1b, 1c, 1d… Power modules; 2, 2a, 2b… Driver circuits; 3a, 3b, 3c… Resistors; 4, 4a, 4b… Inductors; 6, 6a, 6b, 6c, 6d, 6e, 6f… Capacitors; 7a, 7b, 7c, 7d, 7e, 7f… Inductors; 10, 10a, 10b, 10c… Coupling elements; 11a, 11b, 11c… Control signal wiring; 17… Capacitors; 18… Substrate; 22, 23… Impedance characteristics; 27… Series inductors; 28, 28a, 28b, 28c… Main circuit impedance (module group impedance); 29… Loop path; 31a, 31b, 31c, 31d… Module control terminals; 32a, 32… b, 32c… Module first power terminal, 33a, 33b, 33c… Module second power terminal, 39… Resistor, 41, 41a, 41b… Output terminal, 90… Power conversion device, 91, 91a, 91b, 91c, 91d… Main circuit, 92, 92a, 92b, 92c, 92d… Drive circuit, 93… Filter, Cdg1… First module capacitor, Cdg2… Second module capacitor, Cdg3… Third module capacitor, fc… Resonant frequency, fp… Peak frequency, g… Gate (control terminal), N1… Connection point (driver side connection point), N2, N3, N4, N5, N6… Connection point, Tr… Transistor (semiconductor switching element).

Claims

1. A power conversion device, Power conversion of input power is achieved by controlling the conduction period of multiple main circuits with power modules, characterized in that: include: The main circuit in which multiple power modules are connected in parallel; as well as The drive circuit that drives the main circuit The power module includes semiconductor switching elements. Two of the power modules are grouped together as a module group. The driving circuit includes: A driver circuit that generates control signals input to the respective module control terminals of the plurality of power modules; as well as A filter, connected between the driver circuit and the plurality of module control terminals, has an impedance characteristic for each module group that results in a peak shape with increasing impedance in a pre-defined specific frequency band. The filter has a coupling element for each of the module groups, the coupling element comprising a capacitor connected between the control terminals of the two modules.

2. The power conversion device as described in claim 1, characterized in that, The driving circuit includes one of the driver circuits.

3. The power conversion device as described in claim 1, characterized in that, The drive circuit includes the same number of driver circuits as the power module. Each of the power modules is controlled by the control signal of the corresponding driver circuit.

4. The power conversion device as described in claim 1, characterized in that, The driving circuit includes one of the driver circuits. The drive circuit includes control signal wiring that transmits the control signal from the output terminal of the driver circuit to the module control terminal of each of the power modules. For each of the aforementioned module groups The coupling element is connected between the two control signal wires on the control terminal side of the module. The two control signal wirings are connected through the driver-side connection point on the output terminal side of the driver circuit. A series inductor is connected in parallel with the coupling element. This series inductor has an inductance between one connection point of the control signal wiring connected to the coupling element and the driver-side connection point, and another inductance between another connection point of the control signal wiring connected to the coupling element and the driver-side connection point. The filter has an LC parallel circuit consisting of the series inductor and the coupling element for each of the module groups.

5. The power conversion device as described in claim 4, characterized in that, The power module includes a module control terminal, a first module power terminal through which a power greater than the control signal flows, and a second module power terminal that generates a potential as a voltage reference for the control signal. The impedance between one module control terminal and another module control terminal in the module group of the main circuit is taken as the module group impedance. The impedance of the module group is: A first module capacitor between the first power terminal and the control terminal of the power module. The inductance between the first power terminal of one power module and the first power terminal of another power module, and The impedance obtained by connecting the second module capacitor in series between the first power terminal and the control terminal of the other power module. In the filter, For each module group, within ±25% of the resonant frequency of the loop path formed by the two control signal wirings including the series inductor and the impedance of the module group, the peak frequency at which the impedance in the impedance characteristic of the LC parallel circuit corresponding to that module group reaches its peak value is set.

6. The power conversion device as described in claim 4 or 5, characterized in that, The coupling element has inductance between one of the control signal wirings and one end of the capacitor, and between the other end of the capacitor and another of the control signal wirings. The inductance of the coupling element is less than half the value of the series inductance.

7. The power conversion device according to any one of claims 1 to 5, characterized in that, The capacitor of the coupling element is a surface-mount capacitor.

8. The power conversion device according to any one of claims 1 to 7, characterized in that, The drive circuit has a resistor for each of the power modules. The control signal is output to each of the power modules via the resistor.

9. The power conversion device as described in claim 8, characterized in that, The resistor in the driving circuit and the capacitor in the coupling element are mounted on the same substrate.

10. The power conversion device according to any one of claims 1 to 7, characterized in that, In the power module, a resistor is provided between the module control terminal and the control terminal of the semiconductor switching element.

11. The power conversion device according to any one of claims 1 to 10, characterized in that, The semiconductor switching element is a semiconductor switching element that uses a wide-bandgap semiconductor material.

12. The power conversion device according to any one of claims 1 to 11, characterized in that, In the main circuit, the maximum switching speed of multiple power modules reaches over 50kA / μs.

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