JP2019097321A - Power conversion device - Google Patents

Abstract

To provide a power conversion device capable of reducing radiation noise.SOLUTION: A power conversion device comprises, on a multilayer substrate 6, components 4a-4f constituting a diode D1, a diode D2, a switching element Q1, a switching element Q2, a capacitor Cf and a capacitor Cd, and wiring 5 connecting the components 4a-4f with each other. The components 4a-4f are disposed adjacently with each other and disposed in such a manner that a direction of a flowing current becomes substantially opposite at least either between the adjacent components or between a component and the wiring 5 adjacent to the component.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a power converter, and more particularly to a connection point between a first element and a second element formed of a diode or a switching element and a third element and a fourth element formed of a switching element. Power converter provided with a capacitor.

  Conventionally, a power conversion device including a capacitor connected to a connection point of a first element and a second element formed of a diode or a switching element and a connection point of a third element and a fourth element formed of the switching element It is known (for example, refer to patent documents 1).

  Patent Document 1 discloses a DC-DC converter including a switch circuit unit including a first switching element, a second switching element, a third switching element, and a fourth switching element connected in series. In this DC-DC converter, a capacitor (flying capacitor) connected to a connection point of the first switching element and the second switching element and a connection point of the third switching element and the fourth switching element is provided. Further, one end of the chopper reactor is connected between the second switching element and the third switching element. In addition, a smoothing capacitor is connected in parallel to the switch circuit unit.

  In the DC-DC converter described in Patent Document 1, the second switching element and the fourth switching element are turned off, and the first switching element and the third switching element are turned on, whereby the chopper reactor, the third switching A current flows in a path (hereinafter, path 1) via the element, the flying capacitor, and the first switching element. Further, the second switching element and the fourth switching element are turned on, and the first switching element and the third switching element are turned off, whereby the chopper reactor, the second switching element, the flying capacitor, and the fourth switching element A current flows in a path (hereinafter referred to as path 2) via

JP, 2013-192383, A

  However, in the conventional DC-DC converter as described in Patent Document 1, parasitic capacitance may occur in the first switching element and the second switching element which are turned off. In this case, for example, when the first switching element and the third switching element described above are turned on (path 1), a path in which current flows through the parasitic capacitance of the third switching element, the flying capacitor, and the second switching element Hereinafter, route 3) occurs. When the second and fourth switching elements are turned on (path 2), a path through which current flows through the parasitic capacitance of the first switching element, the flying capacitor, the fourth switching element, and the smoothing capacitor (path 2) Hereinafter, the route 4) occurs. And since this path 4 is relatively long (longer than path 3), there is a problem that the radiation noise generated due to the current flowing through this path 4 becomes relatively large.

  The present invention has been made to solve the problems as described above, and one object of the present invention is to provide a power conversion device capable of reducing radiation noise.

  In order to achieve the above object, a power conversion device according to one aspect of the present invention comprises a DC power supply, and a first element, a diode or a switching element, comprising a diode or a switching element connected in series. A switching circuit portion including a second element, a third element formed of a switching element, and a fourth element formed of a switching element, and one end connected to a DC power supply, and connecting the second element and the third element Parallel to the switching circuit part, the first capacitor connected to the reactor whose other end is connected to the point, the connection point of the first element and the second element, and the connection point of the third element and the fourth element Parts constituting each of the second capacitor to be connected, the first element, the second element, the third element, the fourth element, the first capacitor and the second capacitor The components which comprise the wiring to be connected and which constitute each of the second capacitor, the first element, the first capacitor, and the fourth element are arranged adjacent to each other, and between the adjacent components, and the components And at least one of the wirings adjacent to the component, the directions of the flowing current are substantially opposite to each other.

  In the power converter according to one aspect of the present invention, as described above, the components constituting each of the second capacitor, the first element, the first capacitor, and the fourth element are arranged adjacent to each other. In at least one of the adjacent parts and between the part and the wiring adjacent to the part, the directions of the flowing current are substantially opposite to each other. Thus, the radiation noise (magnetic flux) generated by the current flowing in one of the adjacent components (or the wiring adjacent to the component and the component) (current flowing in one direction) and the current flowing in the other (one direction and And the radiation noise (magnetic flux) generated due to the current flowing in the substantially opposite direction mutually cancel each other. As a result, radiation noise can be reduced. As a result, it is possible to suppress the malfunction of the component itself (the second capacitor, the first element, the first capacitor, and the fourth component) and the malfunction of the component (apparatus) disposed around the component.

  In the power converter according to the above aspect, preferably, the components constituting each of the second capacitor, the first element, the first capacitor, and the fourth element are arranged adjacent to each other along a predetermined direction. It is done. According to this structure, all of the components constituting each of the second capacitor, the first element, the first capacitor, and the fourth element are adjacent to each other in a state in which they are arranged along the predetermined direction. The direction of the flowing current can be easily reversed substantially between at least one of the parts and between the parts and the wiring adjacent to the parts.

  In the power converter according to the aforementioned aspect, preferably, the first element, the second element, the third element, the fourth element, the first capacitor, and the second capacitor are provided in the first layer of the multilayer substrate. The wiring is provided in the first layer of the multilayer substrate, and includes a first wiring that connects the second capacitor, the first element, the first capacitor, and the fourth element in this order. According to this structure, the component and the wiring are arranged on the same plane (the first layer of the multilayer substrate), so that the radiation noise (magnetic flux) is canceled on the same plane (the first layer of the multilayer substrate) be able to.

  In this case, preferably, in plan view, the first wiring has a meandering shape, and the parts constituting each of the second capacitor, the first element, the first capacitor, and the fourth element have a meandering shape. It is mutually connected by the 1st wiring. According to this structure, the directions of the current flowing between the adjacent parts in the first wiring having a meandering shape are substantially opposite to each other, so that the wiring adjacent to the parts and between the adjacent parts can be easily made. The direction of the current flowing between and / or may be substantially reversed.

  In the power converter including the second wiring, preferably, the wiring is provided in the second layer of the multilayer substrate so as to overlap the first wiring in plan view, and the fourth element and the second capacitor are electrically connected. And a second wire in which a current flows in a direction substantially opposite to the direction of the current flowing in the first wire. According to this structure, since the direction of the current flowing through the second wiring is substantially opposite to the direction of the current flowing through the first wiring, the radiation noise (magnetic flux) is generated between the first wiring and the second wiring. Can cancel each other out. This can further reduce the radiation noise.

  In this case, preferably, in plan view, the second wiring is provided in the second layer of the multilayer substrate so as to have a path substantially along the path of the first wiring. According to this structure, the radiation noise (magnetic flux) can be effectively canceled out between the first wiring and the second wiring.

  In the power converter according to the aforementioned aspect, preferably, the first capacitors include one side first capacitor and the other side first capacitor connected in parallel with one another, and the second capacitor, the first element, one side first The components constituting each of the first capacitor, the fourth element, the other first side capacitor, the third element and the second element are arranged adjacent to each other, and between adjacent parts, between parts, in parts and parts The direction of the flowing current is arranged to be substantially opposite in at least one of the adjacent wirings. According to this structure, even if the radiation noise generated in the series circuit including the other side first capacitor, the third element and the second element becomes large, the other side first capacitor, the third element and the second element Since at least one of the components constituting each and / or between the component and the wiring adjacent to the component has a substantially opposite direction of flowing current, the radiation noise generated in the series circuit is also reduced. be able to. Further, unlike the case where one relatively large first capacitor is arranged, arrangement of the relatively small one-side first capacitor and the other-side first capacitor divided into two can be easily performed.

  In the power converter according to the aforementioned aspect, preferably, at least one of the first element, the second element, the third element and the fourth element is made of a wide band gap semiconductor. Here, since the wide band gap semiconductor can be switched at high speed (that is, the switching frequency is high), the energy of the radiation noise becomes relatively large. Therefore, in the case where at least one of the first element, the second element, the third element, and the fourth element is made of a wide band gap semiconductor, wiring between adjacent parts and parts and parts adjacent to each other It is particularly effective to reduce the radiation noises by arranging the components so that the directions of the current flowing in at least one of them are opposite to each other. In addition, radiation noise due to a wide band gap semiconductor having a relatively large radiation noise can be reduced without separately providing a component for noise suppression. As a result, it is possible to reduce the radiation noise while suppressing an increase in size of the power converter.

  According to the present invention, as described above, radiation noise can be reduced.

It is a circuit diagram showing the whole power conversion device composition by a 1st embodiment. It is a circuit diagram (1) for demonstrating operation | movement of a power converter device. It is a circuit diagram (2) for demonstrating operation | movement of a power converter device. It is a circuit diagram (3) for demonstrating operation | movement of a power converter device. It is a circuit diagram (4) for demonstrating the operation | movement of a power converter device. It is a figure which shows arrangement | positioning (1st layer of a multilayer substrate) of the components of the power converter device by 1st Embodiment. FIG. 2 is a diagram in which the circuit diagram of FIG. 1 is rewritten along the arrangement of parts. It is a figure which shows the multilayer substrate by 1st Embodiment. It is a figure which shows the 2nd layer of the multilayer substrate by 1st Embodiment. It is a circuit diagram which shows the whole structure of the power converter device by 2nd Embodiment. It is a figure which shows arrangement | positioning (1st layer of a multilayer substrate) of the components of the power converter device by 2nd Embodiment. FIG. 11 is a diagram in which the circuit diagram of FIG. 10 is rewritten along the arrangement of parts. It is a circuit diagram which shows the whole structure of the power converter device by a modification.

  Hereinafter, an embodiment of the present invention will be described based on the drawings.

First Embodiment
The configuration of the power conversion device 100 according to the first embodiment will be described with reference to FIGS. 1 to 9.

(Configuration of power converter)
As shown in FIG. 1, the power conversion device 100 is configured to convert the voltage Vin of the DC power supply 1 and supply the voltage Vin to the load 101. For example, power converter 100 is configured as a so-called boost chopper.

  In addition, reactor 2 (chopper reactor) is provided in power conversion device 100. One end of the reactor 2 is connected to the DC power supply 1. Further, the other end of the reactor 2 is connected to a connection point A1 between a diode D2 described later and the switching element Q1.

  Further, the power conversion apparatus 100 is provided with the switching circuit unit 3. The switching circuit unit 3 includes a diode D1, a diode D2, a switching element Q1, and a switching element Q2. The diode D1, the diode D2, the switching element Q1, and the switching element Q2 are connected in series in this order. Specifically, the source of the switching element Q1 is connected to the drain of the switching element Q2. The anode of the diode D2 is connected to the drain of the switching element Q1. The anode of the diode D1 is connected to the cathode of the diode D2. The diode D1 and the diode D2 are examples of the “first element” and the “second element” in the claims respectively. The switching element Q1 and the switching element Q2 are examples of the “third element” and the “fourth element” in the claims respectively.

  Here, in the first embodiment, the diode D1 and the diode D2 are formed of a Schottky barrier diode formed of a wide band gap semiconductor (for example, SiC).

  Switching element Q1 and switching element Q2 are formed of, for example, a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), or the like. In the first embodiment, the switching element Q1 and the switching element Q2 are made of a wide band gap semiconductor (for example, SiC).

  Further, the power conversion device 100 is provided with a capacitor Cf. The capacitor Cf is connected to a connection point A2 of the diode D1 and the diode D2, and a connection point A3 of the switching element Q1 and the switching element Q2. The capacitor Cf is called a flying capacitor. Further, the capacitor Cf is an example of the “first capacitor” in the claims.

  Further, the power conversion device 100 is provided with a capacitor Cd (direct current capacitor) connected in parallel to the switching circuit unit 3. Specifically, the positive potential side of the capacitor Cd is connected to the cathode of the diode D1, and the negative potential side of the capacitor Cd is connected to the source of the switching element Q2. The reactor 2, the diode D1, the diode D2, the switching element Q1, the switching element Q2, the capacitor Cf, and the capacitor Cd constitute a flying capacitor type chopper. The capacitor Cd is an example of the “second capacitor” in the claims.

(Operation of power converter)
Next, the operation of the power conversion device 100 will be described with reference to FIGS. In the following description, the forward voltage drop of the diode D1, the diode D2, the switching element Q1, the switching element Q2, etc. is ignored. Further, in FIGS. 2 to 5, the voltage of the capacitor Cf is maintained at approximately E / 2 during operation of the power conversion device 100. This makes it possible to suppress the application of an overvoltage to the switching element Q2 when the diode D1 and the diode D2 conduct.

  As shown in FIG. 2, both the switching element Q1 and the switching element Q2 are turned on. As a result, the voltage value of the voltage Vr is substantially zero and no current flows in the capacitor Cf.

  Further, as shown in FIG. 3, the switching element Q1 is turned off and the switching element Q2 is turned on. Thus, the voltage value of the voltage Vr is approximately E / 2 and a current flows in the capacitor Cf. As a result, the capacitor Cf is charged. Here, a parasitic capacitance Cs1 is generated in the diode D1. As a result, a path B1 (see the dotted line in FIG. 3) for charging the parasitic capacitance Cs1 via the diode D1, the capacitor Cf, the switching element Q2 and the capacitor Cd is generated. The length of the path B1 is longer than the path B2 (see the dotted line in FIG. 4) described later. Therefore, when the switching element Q2 is turned on, relatively large radiation noise (magnetic flux) is generated due to the current flowing through the path B1.

  Further, as shown in FIG. 4, the switching element Q1 is turned on and the switching element Q2 is turned off. Thus, the voltage value of the voltage Vr is approximately E / 2, and the capacitor Cf is discharged. The capacitance of the capacitor Cf is assumed to be sufficiently large for one charge and one discharge. In addition, the voltage fluctuation due to charge and discharge is small (for example, 10% or less of E / 2). Here, a parasitic capacitance Cs2 is generated in the diode D2. As a result, a path B2 (see the dotted line in FIG. 4) for charging the parasitic capacitance Cs2 via the diode D2, the switching element Q1 and the capacitor Cf is generated. In addition, since the length of the path B2 is shorter than the path B1 (see the dotted line in FIG. 3), the generated radiation noise (magnetic flux) is relatively small.

  Further, as shown in FIG. 5, the switching element Q1 is turned off and the switching element Q2 is turned off. As a result, the voltage value of the voltage Vr becomes E, and no current flows in the capacitor Cf.

(Specific structure of power converter)
Next, a specific structure of power converter 100 will be described.

  As shown in FIG. 6, in power conversion apparatus 100, components 4 (components 4a to 4f) constituting each of diode D1, diode D2, switching element Q1, switching element Q2, capacitor Cf and capacitor Cd are connected to each other. Wiring 5 is provided. The components 4a to 4f respectively mean the capacitor Cd, the diode D1, the capacitor Cf, the switching element Q2, the diode D2, and the switching element Q1 itself. Moreover, the wiring 5 is comprised by the wiring pattern (The wiring 5 of the flat shape whose width | variety is comparatively wide with respect to thickness). As a result, it is possible to easily overlap (overlap) the first wiring 51 and the second wiring 52 described later in plan view.

  Further, FIG. 7 is a diagram in which the circuit diagram of FIG. 1 is rewritten along the arrangement of the component 4 of FIG. That is, the arrangement of the parts 4 of FIG. 6 and the electrical connection between the parts 4 are the same as the circuit part of FIG.

  Here, in the first embodiment, as shown in FIG. 6, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the component 4a, the component 4b, the component 4c, and the component 4d constituting them) are adjacent to each other It is arranged as. The capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the component 4a, the component 4b, the component 4c, and the component 4d that configure them) are adjacent to the component 4 and the component 4 between adjacent components 4 At least one of the wiring 5 and the wiring 5, the direction of the flowing current is substantially opposite. The details will be described below.

  Specifically, in the first embodiment, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the component 4a, the component 4b, the component 4c, and the component 4d that configure them) are arranged along the X direction. It is arranged to be adjacent to each other. The capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 are disposed in this order from the X1 direction side toward the X2 direction side. The X direction is an example of the “predetermined direction” in the claims. Further, the expression “arranged along the X direction” also includes the case where the capacitor Cd, the diode D1, the capacitor Cf and the switching element Q2 are slightly deviated from each other in the Y direction. Note that the degree to which this deviation is permitted is within a distance where it is possible to mutually cancel radiation noise described later. Further, the diode D2 and the switching element Q1 are respectively shifted in the Y1 direction side and the Y2 direction side with respect to the capacitor Cd, the diode D1, the capacitor Cf and the switching element Q2 arranged along the X direction. It is arranged.

  Further, it is desirable that the distance between the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 adjacent to each other be as small as possible (the shortest distance). As a result, the power converter 100 can be miniaturized, and radiation noise described later can be further reduced.

  In the first embodiment, the diode D1, the diode D2, the switching element Q1, the switching element Q2, the capacitor Cf, and the capacitor Cd are provided in the first layer 6a of the multilayer substrate 6. The wiring 5 is provided in the first layer 6a of the multilayer substrate 6, and includes a first wiring 51 connecting the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 in this order. In addition, in plan view, the first wiring 51 has a meandering shape. The capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the component 4a, the component 4b, the component 4c, and the component 4d constituting them) are connected to each other by the first wiring 51 having a meandering shape.

  Specifically, the negative potential side of the capacitor Cd is connected to the first wiring portion 51a having a substantially linear shape. The positive potential side of the capacitor Cd and the cathode of the diode D1 are connected by a first wiring portion 51b having a substantially U shape. Further, the anode of the diode D1 and the positive potential side of the capacitor Cf are connected by the first wiring portion 51c having a substantially S-shape. Further, the negative potential side of the capacitor Cf and the drain of the switching element Q2 are connected by a first wiring portion 51d having a substantially S shape. The source of the switching element Q2 is connected to a first wiring portion 51e having a substantially linear shape. The diode D2 is electrically connected to the first wiring portion 51c, and the switching element Q1 is electrically connected to the first wiring portion 51d.

  Then, as described above, by providing the capacitor Cd, the diode D1, the capacitor Cf, the switching element Q2, and the first wiring 51, the switching element Q2 is adjacent in the on state (path B1, see FIG. 3). In the capacitor Cd and the diode D1 arranged, the direction of the current flowing in the capacitor Cd is the Y1 direction, while the direction of the current flowing in the diode D1 is the Y2 direction (opposite to the Y1 direction). Further, in the diode D1 and the first wiring portion 51c arranged to be adjacent to each other, the direction of the current flowing in the diode D1 is the Y2 direction, and the direction of the current flowing in the first wiring portion 51c is the Y1 direction is there.

  Further, in the first wiring portion 51c and the capacitor Cf arranged to be adjacent to each other, the direction of the current flowing through the first wiring portion 51c is Y1, while the direction of the current flowing through the capacitor Cf is Y2 is there. Further, in the capacitor Cf and the first wiring portion 51d arranged to be adjacent to each other, the direction of the current flowing through the capacitor Cf is the Y2 direction, and the direction of the current flowing through the first wiring portion 51d is the Y1 direction is there. Further, in the first wiring portion 51d and the switching element Q2 arranged to be adjacent to each other, the direction of the current flowing through the first wiring portion 51d is Y1, while the direction of the current flowing through the switching element Q2 is Y2 It is a direction. Thereby, between the capacitor Cd and the diode D1, between the diode D1 and the first wiring portion 51c, between the first wiring portion 51c and the capacitor Cf, between the capacitor Cf and the first wiring portion 51d, Radiation noise (magnetic flux) is reduced (cancelled) between the wiring portion 51d and the switching element Q2.

  In the first embodiment, as shown in FIGS. 8 and 9, the wiring 5 is provided on the second layer 6b of the multilayer substrate 6 so as to overlap the first wiring 51 in plan view, and the switching element Q2 is formed. And a second wiring 52 electrically connecting the capacitor Cd to the capacitor Cd. Then, as shown in FIG. 9, the second wiring 52 is configured such that the current flows in the direction substantially opposite to the direction of the current flowing through the first wiring 51. Specifically, in plan view, the second wiring 52 is provided in the second layer 6 b of the multilayer substrate 6 so as to have a path substantially along the path of the first wiring 51. That is, like the first wiring 51, the second wiring 52 has a meandering shape.

  Specifically, the second wiring 52 has the same shape as the first wiring portion 51 a to the first wiring portion 51 e of the first wiring 51. Then, in a plan view, the first wiring 51 and the second wiring 52 substantially overlap (overlap). The first wiring 51 and the second wiring 52 are connected by the via 53 (see FIG. 8). The current flowing from the positive potential side of the capacitor Cd flows to the negative potential side of the capacitor Cd via the diode D1, the capacitor Cf, the switching element Q2, the via 53, the second wiring 52, and the via 53. Thereby, the radiation noise (magnetic flux) generated by the current flowing through the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 is reduced (cancelled) by the radiation noise (magnetic flux) generated by the current flowing through the second wiring 52 .

[Effect of First Embodiment]
In the first embodiment, the following effects can be obtained.

  In the first embodiment, as described above, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the component 4a, the component 4b, the component 4c, and the component 4d constituting them) are arranged adjacent to each other In at least one of the parts 4 adjacent to each other and the wiring 5 adjacent to the part 4, the directions of the flowing current are substantially opposite to each other. Thus, the radiation noise (magnetic flux) generated by the current flowing in one of the adjacent components 4 (or the wiring 5 adjacent to the components 4 and 4) (the current flowing in one direction) and the current flowing in the other The radiation noise (magnetic flux) generated by (a current flowing in a direction substantially opposite to the one direction) cancels each other. As a result, radiation noise can be reduced. As a result, it is possible to suppress malfunction of the component 4 itself (the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2) and malfunction of components (devices) arranged around the component 4.

  In the first embodiment, as described above, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 (the components 4a, 4b, 4c, and 4d that configure them) are arranged along the X direction. , Are arranged adjacent to each other. As a result, all of the components 4 constituting each of the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 are adjacent to each other in the state of being arranged along the X direction. In at least one of the part 4 and the wiring 5 adjacent to the part 4, the direction of the flowing current can be easily reversed.

  In the first embodiment, as described above, the wiring 5 is provided in the first layer 6a of the multilayer substrate 6, and the first connecting the capacitor Cd, the diode D1, the capacitor Cf and the switching element Q2 in this order Wiring 51 is included. As a result, the component 4 and the wiring 5 are arranged on the same plane (the first layer 6a of the multilayer substrate 6), so radiation noise (magnetic flux) in the same plane (the first layer 6a of the multilayer substrate 6) We can cancel each other.

  In the first embodiment, as described above, the components 4 constituting each of the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 are connected to each other by the first wiring 51 having a meandering shape in plan view It is done. Thereby, in the first wiring 51 having a meandering shape, the direction of the current flowing to the adjacent components 4 is substantially opposite, so that the adjacent components 4 are easily adjacent to the components 4 and 4. The direction of the current flowing between at least one of the wiring 5 and the wiring 5 can be substantially reversed.

  In the first embodiment, as described above, the wiring 5 is provided in the second layer 6b of the multilayer substrate 6 so as to overlap the first wiring 51 in plan view, and the switching element Q2 and the capacitor Cd are formed. It includes a second wiring 52 which is electrically connected and in which a current flows in a direction substantially opposite to the direction of the current flowing in the first wiring 51. Thus, since the direction of the current flowing through the second wire 52 is substantially opposite to the direction of the current flowing through the first wire 51, the radiation noise (magnetic flux) is generated between the first wire 51 and the second wire 52. Can cancel each other out. This can further reduce the radiation noise.

  In the first embodiment, as described above, the second wiring 52 is provided in the second layer 6 b of the multilayer substrate 6 so as to have a path substantially along the path of the first wiring 51 in plan view. It is done. Thus, radiation noise (magnetic flux) can be effectively canceled out between the first wiring 51 and the second wiring 52.

  In the first embodiment, as described above, the diode D1, the diode D2, the switching element Q1, and the switching element Q2 are formed of wide band gap semiconductors. Here, since the wide band gap semiconductor can be switched at high speed (that is, the switching frequency is high), the energy of the radiation noise becomes relatively large. Therefore, in the case where the diode D1, the diode D2, the switching element Q1 and the switching element Q2 are formed of wide band gap semiconductors, between the parts 4 adjacent to each other and between the parts 4 and the wiring 5 adjacent to the parts 4 Placing the component 4 so that the direction of the current flowing in at least one of the above is substantially opposite is particularly effective in reducing the radiation noise. In addition, radiation noise due to a wide band gap semiconductor having a relatively large radiation noise can be reduced without separately providing a component for noise suppression. As a result, it is possible to reduce the radiation noise while suppressing the power converter 100 from increasing in size.

Second Embodiment
Next, the configuration of the power conversion device 200 according to the second embodiment will be described with reference to FIGS. In the second embodiment, the capacitors Cf1 and Cf2, which are flying capacitors, are connected in parallel with each other. The capacitor Cf1 and the capacitor Cf2 are examples of the "first side first capacitor" and the "other side first capacitor" in the claims, respectively.

  As shown in FIG. 10, in power conversion apparatus 200, capacitor Cf1 and capacitor Cf2 are connected in parallel to each other. In FIG. 10, the configuration on the circuit diagram except that capacitor Cf1 and capacitor Cf2 are connected in parallel to each other is the same as the circuit diagram of power converter 100 of the first embodiment shown in FIG. is there.

  Here, in the second embodiment, as shown in FIGS. 11 and 12, in the power conversion device 200, the capacitor Cd, the diode D1, the capacitor Cf1, the switching element Q2, the capacitor Cf2, the switching element Q1 and the diode D2 The component 4a, the component 4b, the component 41c, the component 4d, the component 42c, the component 4f, and the component 4e) are arranged to be adjacent to each other. In addition, between the parts 4 adjacent to each other, and between the parts 4 and the wiring 105 adjacent to the part 4, the directions of the flowing current are substantially opposite to each other.

  The capacitor Cd, the diode D1, the capacitor Cf1, the switching element Q2, the capacitor Cf2, the switching element Q1 and the diode D2 are connected to each other by a wiring 105 formed of a pattern wiring. Here, the configuration of the capacitor Cd, the diode D1, the capacitor Cf1, and the switching element Q2 is the same as the configuration in which the capacitor Cf of the power conversion device 100 of the first embodiment is replaced with the capacitor Cf1.

  The positive potential side of the capacitor Cf2 and the diode D2 are connected by a first wiring portion 105a having a substantially U shape. The diode D2 and the switching element Q1 are connected by a first wiring portion 105b having a substantially S-shape. The switching element Q1 and the negative potential side of the capacitor Cf2 are connected by the first wiring portion 105c having a substantially U shape. The first wiring portions 105a, 105b and 105c connecting the capacitor Cf2, the switching element Q1 and the diode D2 are provided on the first layer 6a of the multilayer substrate 6, and the second layer 6b is connected to the capacitor Cf2, A wire connecting the switching element Q1 and the diode D2 is not provided.

  And, between the capacitor Cf2 and the switching element Q1 adjacent to each other, the direction of the flowing current is substantially opposite. In addition, the direction of the flowing current is substantially opposite between the diode D2 and the first wiring portion 105b adjacent to each other. In addition, the direction of the flowing current is substantially opposite between the adjacent first wiring portion 105b and the switching element Q1. This makes it possible to reduce (cancel) the radiation noise (magnetic flux) between adjacent components 4 or between the adjacent components 4 and the wiring 105. That is, when the radiation noise in the series circuit (switching element Q1 is on, see FIG. 4) consisting of the switching element Q1, the diode D2 and the capacitor Cf becomes relatively large, the capacitor Cf (first embodiment) By replacing the capacitor Cf2 and the capacitor Cf2 in parallel (second embodiment), it is possible to reduce the radiation noise of the above-described series circuit.

[Effect of Second Embodiment]
In the second embodiment, the following effects can be obtained.

  In the second embodiment, as described above, the capacitor Cd, the diode D1, the capacitor Cf1, the switching element Q2, the capacitor Cf2, the switching element Q1 and the diode D2 (the components 4a, 4b, 41c, 4d The component 42c, the component 4f, and the component 4e) are arranged adjacent to each other, and at least one of between the adjacent components 4 and between the component 4 and the wiring 105 adjacent to the component 4 , And the directions of the flowing current are substantially opposite to each other. Thereby, even if the radiation noise generated in the series circuit including capacitor Cf2, switching element Q1 and diode D2 becomes large, between components 4 constituting each of capacitor Cf2, switching element Q1 and diode D2, and Since at least one of the part 4 and the wiring 105 adjacent to the part 4 has the current flowing in substantially the opposite direction, radiation noise generated in the series circuit can also be reduced. Further, unlike the case where one relatively large capacitor Cf is arranged, arrangement of relatively small capacitors Cf1 and Cf2 divided into two can be easily performed.

[Modification]
It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is indicated not by the description of the embodiments described above but by the claims, and further includes all modifications (modifications) within the meaning and scope equivalent to the claims.

  For example, in the first and second embodiments, an example is shown in which the directions of the flowing current are substantially opposite in both between adjacent parts and between the part and the wiring adjacent to the part. The present invention is not limited to this. For example, the direction of the flowing current may be substantially opposite between only one of the adjacent parts and between the part and the wiring adjacent to the part. That is, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 may be disposed adjacent to each other such that the directions of the current flowing between adjacent parts are substantially opposite.

  In the first and second embodiments described above, the present invention is applied to a power conversion device in which the diode D1, the diode D2, the switching element Q1, and the switching element Q2 are connected in series. It is not restricted to this. For example, as shown in FIG. 13, the present invention can also be applied to a power conversion device 300 according to a modification in which switching element Q11 and switching element Q12 are provided instead of diode D1 and diode D2.

  In the first and second embodiments, the capacitor Cd, the diode D1, the capacitor Cf, and the switching element Q2 are arranged along the X direction, but the present invention is not limited to this. . For example, capacitor Cd and diode D1 are arranged along the X direction so that the directions of flowing current are opposite to each other, and capacitor Cf and switching element Q2 are along the Y direction so that the directions of flowing current are opposite to each other It may be arranged as follows.

  Further, in the first and second embodiments, an example is shown in which the wiring includes the first wiring provided in the first layer of the multilayer substrate and the second wiring provided in the second layer of the multilayer substrate. The present invention is not limited to this. For example, the wiring may be constituted only by the first wiring provided in the first layer of the multilayer substrate.

  In the first and second embodiments described above, the second wiring has a meandering shape like the first wiring. However, the present invention is not limited to this. For example, the second wiring may be configured to linearly connect the switching element Q2 and the negative potential side of the capacitor Cd.

  In the first and second embodiments, the example in which all of the diode D1, the diode D2, the switching element Q1 and the switching element Q2 are formed of wide band gap semiconductors is shown, but the present invention is limited to this. Absent. For example, only one of the diode D1, the diode D2, the switching element Q1, and the switching element Q2 may be made of a wide band gap semiconductor.

REFERENCE SIGNS LIST 1 DC power supply 2 reactor 4, 4 a to 4 f, 41 c, 42 c parts 5, 105 wiring 6 multilayer substrate 6 a first layer 6 b second layer 51 first wiring 52 second wiring 100, 200, 300 power converter A 1, A2, A3 Connection point Cd capacitor (second capacitor)
Cf capacitor (first capacitor)
Cf1 capacitor (one side first capacitor)
Cf2 capacitor (other side first capacitor)
D1 diode (first element)
D2 diode (second element)
Q1 switching element (third element)
Q2 switching element (fourth element)

Claims (8)

DC power supply,
A first element composed of a diode or a switching element, a second element composed of the diode or the switching element, a third element composed of the switching element, and the switching element connected in series with each other A switching circuit unit including a fourth element,
A reactor having one end connected to the DC power supply and the other end connected to a connection point between the second element and the third element;
A first capacitor connected to a connection point of the first element and the second element, and a connection point of the third element and the fourth element;
A second capacitor connected in parallel to the switching circuit unit;
And a wire connecting parts constituting each of the first element, the second element, the third element, the fourth element, the first capacitor, and the second capacitor,
The parts constituting each of the second capacitor, the first element, the first capacitor, and the fourth element are arranged adjacent to each other, and between the adjacent parts and the parts And at least one of the wiring adjacent to the component and the wiring adjacent to the component, wherein the direction of the flowing current is substantially opposite.   The parts constituting each of the second capacitor, the first element, the first capacitor and the fourth element are disposed adjacent to each other along a predetermined direction. Power converter as described. The first element, the second element, the third element, the fourth element, the first capacitor, and the second capacitor are provided in a first layer of a multilayer substrate,
The wiring is provided in the first layer of the multilayer substrate, and includes a first wiring that connects the second capacitor, the first element, the first capacitor, and the fourth element in this order. The power converter device according to 1 or 2. In plan view, the first wiring has a meandering shape,
The said components which comprise each of a said 2nd capacitor | condenser, a said 1st element, a said 1st capacitor | condenser, and a 4th element are mutually connected by the said 1st wiring which has a meandering shape. Power converter.   The wiring is provided in the second layer of the multilayer substrate so as to overlap the first wiring in a plan view, and electrically connects the fourth element and the second capacitor to the first wiring. The power conversion device according to claim 3, further comprising a second wire through which current flows in a direction substantially opposite to the direction of the flowing current.   The power conversion device according to claim 5, wherein the second wiring is provided in the second layer of the multilayer substrate so as to have a path substantially along a path of the first wiring in a plan view. . The first capacitors include one side first capacitor and the other side first capacitor connected in parallel with each other,
The parts constituting each of the second capacitor, the first element, the one side first capacitor, the fourth element, the other side first capacitor, the third element and the second element are adjacent to each other And at least one of between the adjacent parts and between the part and the wiring adjacent to the part, the direction of the flowing current is substantially opposite. The power converter device according to any one of claims 1 to 6.   The power according to any one of claims 1 to 7, wherein at least one of the first element, the second element, the third element and the fourth element is made of a wide band gap semiconductor. Converter.

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