JP2013005498A - Electric power conversion apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric power conversion apparatus which suppresses the temperature rise while taking measures for noise and serge.SOLUTION: A power module 4 is mounted on a first surface S1 of a substrate 20, and a gate drive circuit 6, multiple electrolytic capacitors C1, and components of a snubber circuit 8 are mounted on a second surface S2 of the substrate 20. The multiple electrolytic capacitors C1 are disposed at two regions 23, 25 so as to be separated from each other and form a clearance 21 at the center of the substrate 20. The components of the snubber circuit are disposed in a region 29 enclosed by the multiple electrolytic capacitors C1.

Description

  The present invention relates to a power conversion device.

FIG. 1 is a diagram illustrating a configuration of a power conversion device including an inverter. Power converter 2 of FIG. 1 is a converter of three phases, U-phase, V-phase, and the power transistor _M1 U _{to M1 W,} M2 U -M2 power module _{4 W} is built of W-phase, the power transistor M1 comprising a _{U ~M1 W, M2 U ~M2} gate drive circuit 6 for driving the _W, the smoothing capacitor C1 and the snubber circuit 8 is an electrolytic capacitor. In FIG. 1, only the U phase is shown, and the V phase and the W phase are omitted.

Japanese Patent Laid-Open No. 7-241087

Upper power supply line LP and lower power supply line LN are connected to the anode and cathode of power supply 5, respectively. The power module 4 includes, for each phase, a high-side transistor M1 and a low-side transistor M2 that are sequentially provided in series between the upper power supply line LP and the lower power supply line LN. Focusing on the U phase, when the high side transistor M1 _U is on, the U phase output OUTU is at a high level, and when the low side transistor M2 _U is on, the U phase output OUTU is at a low level.

  If noise is superimposed on the control signals G1 and G2 for the power transistors M1 and M2 generated by the gate drive circuit 6, the power transistors M1 and M2 may operate unintentionally. As a countermeasure against this, it is desirable that the smoothing capacitor C1 and the snubber circuit 8 are arranged in the immediate vicinity of the power module 4.

  On the other hand, the power module 4 and the smoothing capacitor C <b> 1 that is an electrolytic capacitor generate heat in the operating state of the power converter 2. Therefore, if they are arranged close to each other, they may affect each other thermally and cause the temperature of both to rise. Excessive temperature rise is undesirable because it affects the life of electrolytic capacitors and power modules.

  The present invention has been made in view of such problems, and one of the exemplary purposes of an aspect thereof is to provide a power conversion device capable of suppressing temperature rise while taking measures against noise and surge.

  An embodiment of the present invention relates to a power conversion device that supplies power to a load. The power converter includes an upper power line and a lower power line, a plurality of electrolytic capacitors provided in parallel between the upper power line and the lower power line, and an upper power line and a lower power line, respectively. A power module that has an upper power supply terminal and a lower power supply terminal that are electrically connected to each other, and that includes at least one power transistor provided between the upper power supply terminal and the lower power supply terminal, and at least one power transistor Drive circuit, a snubber circuit electrically connected to the upper power supply line and the lower power supply line, a power module mounted on the first surface, a gate drive circuit on the second surface, and a plurality of electrolysis And a substrate on which components of a capacitor and a snubber circuit are mounted. The plurality of electrolytic capacitors are arranged in at least two regions so as to have a clearance in the center of the substrate, and the components of the snubber circuit are arranged in a region surrounded by the plurality of electrolytic capacitors.

  According to this aspect, the thermal interaction between the electrolytic capacitor and the power module can be reduced by arranging the plurality of electrolytic capacitors so as to avoid the center of the substrate where the heat concentration of the power module occurs. In addition, by arranging the snubber circuit components that are lower in height than the electrolytic capacitors in the area surrounded by the electrolytic capacitors, the upper part of the snubber circuit components can be used as an air flow path. Capacitor heat can be effectively released. Accordingly, it is possible to prevent the temperature of the electrolytic capacitor and the power module from rising excessively while maintaining countermeasures against noise and surge caused by the electrolytic capacitor and the snubber circuit.

The substrate forms a plane perpendicular to the ground in actual use, and the clearance may be provided along a direction perpendicular to the ground.
Heated air flows from low to high. Therefore, by providing the clearance in the direction perpendicular to the ground, the air heated along the clearance can be efficiently exhausted.

Each electrolytic capacitor may be arranged such that another electrolytic capacitor is not adjacent in at least one of the four directions.
As a result, heat concentration on a certain electrolytic capacitor can be prevented.

In each region, the electrolytic capacitors may be arranged in a line on a straight line. Further, the plurality of electrolytic capacitors may be arranged along the direction perpendicular to the ground in the actual use state.
As a result, a clearance is generated on both sides of the row of electrolytic capacitors, and the heat of the electrolytic capacitors can be released from the clearance on both sides.

  Another aspect of the present invention is also a power converter. The power converter includes an upper power line and a lower power line, a plurality of electrolytic capacitors provided in parallel between the upper power line and the lower power line, and an upper power line and a lower power line, respectively. A power module that has an upper power supply terminal and a lower power supply terminal that are electrically connected to each other, and that includes at least one power transistor provided between the upper power supply terminal and the lower power supply terminal, and at least one power transistor Drive circuit, a snubber circuit electrically connected to the upper power supply line and the lower power supply line, a power module mounted on the first surface, a gate drive circuit on the second surface, and a plurality of electrolysis And a substrate on which components of a capacitor and a snubber circuit are mounted. The plurality of electrolytic capacitors are arranged in a staggered manner, and the components of the snubber circuit are arranged in a region surrounded by the plurality of electrolytic capacitors.

  According to this aspect, since each electrolytic capacitor is not adjacent to another capacitor, heat concentration can be prevented. In addition, by arranging the snubber circuit components that are lower in height than the electrolytic capacitor in the area surrounded by the electrolytic capacitors, the upper part of the snubber circuit components can be used as an air flow path. Can effectively release the heat. Accordingly, it is possible to prevent the temperature of the electrolytic capacitor and the power module from rising excessively while maintaining countermeasures against noise and surge caused by the electrolytic capacitor and the snubber circuit.

  Note that any combination of the above-described constituent elements and the constituent elements and expressions of the present invention replaced with each other among methods, apparatuses, systems, and the like are also effective as an aspect of the present invention.

  According to the present invention, it is possible to suppress an increase in temperature while taking measures against noise and surge.

It is a figure which shows the structure of power converters including an inverter. 2A and 2B are diagrams illustrating a configuration of the power conversion device according to the embodiment. FIGS. 3A and 3B are diagrams illustrating the configuration of the power conversion device according to the first modification. 4A and 4B are diagrams illustrating a configuration of a power conversion device according to a second modification.

  2A and 2B are diagrams illustrating a configuration of the power conversion device 2 according to the embodiment. 2A is a perspective view of the power converter 2, and FIG. 2B is a side view of the power converter 2. FIG.

  The power converter 2 supplies power to a load (not shown). An equivalent circuit diagram of the power conversion device 2 is, for example, as described in FIG.

  The power conversion device 2 includes an upper power supply line LP, a lower power supply line LN, a smoothing electrolytic capacitor C1, a power module 4, a gate drive circuit 6, a snubber circuit 8, and a substrate 20. First, the electrical connection relationship of each member will be described with reference to FIG.

  As shown in FIG. 1, the upper power supply voltage LP and the lower power supply voltage VSS are supplied from the power supply 5 to the upper power supply line LP and the lower power supply line LN. The smoothing capacitor C1 is electrically connected between the upper power supply line LP and the lower power supply line LN. The smoothing capacitor C1 realizes a large capacity by connecting a plurality of electrolytic capacitors C1 in parallel.

  The power module 4 has an upper power supply terminal P electrically connected to the upper power supply line LP, a lower power supply terminal N electrically connected to the lower power supply line LN, and the upper power supply terminal P and the lower power supply. At least one power transistor M1, M2 provided between the terminals N is incorporated. The power module 4 may be single-phase or multi-phase, and the number of phases is not limited.

  The gate drive circuit 6 drives the power transistors M1 and M2 constituting the power module 4. The snubber circuit 8 is a protection circuit that absorbs a transient high voltage generated when the power transistors M1 and M2 are switched, and is electrically connected to the upper power supply line LP, the lower power supply line LN, and the output terminal OUT. . For example, in the configuration example of FIG. 1, the capacitor C2 forms a C snubber, and the resistors R1, R2, capacitors C3, C4, and diodes D1, D2 form an RCD snubber. The configuration of the snubber circuit 8 is not particularly limited and may be an arbitrary configuration. The snubber circuit 8 is provided for each phase.

  Next, with reference to FIGS. 2A and 2B, the electrical and mechanical connection relationships of the respective members will be described. 2A and 2B, the upper power supply line LP and the lower power supply line LN are omitted.

  The power module 4 is mounted on the first surface S1 of the substrate 20, and the components C2 to C4, R1, R2, D1, D2 of the gate drive circuit 6, the snubber circuit 8 and a plurality of components are mounted on the second surface S2 opposite thereto. The electrolytic capacitor C1 is mounted. A heat sink 10 is attached to the surface of the power module 4.

  The plurality of electrolytic capacitors C <b> 1 are arranged with at least two regions 23 and 25 so as to have a clearance 21 at the center of the substrate 20. The board | substrate 20 is arrange | positioned so that the plane perpendicular | vertical to the ground may be made | formed in the actual use state of the power converter device 2. FIG. The clearance 21 is provided along the direction perpendicular to the ground.

  Each electrolytic capacitor is arranged such that another electrolytic capacitor is not adjacent in at least one of the four directions (up and down, left and right). This is to prevent heat concentration by surrounding the four sides with another electrolytic capacitor. In the power conversion device 2 of FIG. 2A, the electrolytic capacitors C1a and C1b are in contact with another electrolytic capacitor in three directions, but the other electrolytic capacitors are adjacent to another electrolytic capacitor in only one direction. Three directions are open.

Component _C2 U snubber circuit _{8, V, W ~C4 U,} V, W, R1 U, V, W, R2 U, V, W, D1 U, V, W, D2 U, V, W , a plurality It is arranged in a region 29 of a one-dot chain line surrounded by the electrolytic capacitor C1. For example, capacitors C2 and C3 and resistors R1 and R2 are DIP (Dual Inline Package) components, and diodes D1 and D2 are chip components.

The power module 4 has U, V, and W phase output terminals OUTU, OUTV, and OUTW, respectively. Among the components of the RCD snubber circuit 8, U-phase components R1 _U , R2 _U , C3 _U , C4 _U , D1 _U , D2 _U are located above the output terminal OUTU and V-phase components R1 _V , R2 _V , C3 _V , C4 _V , D1 _V , D2 _V are provided above the output terminal OUTV, and W-phase components R1 _W , R2 _W , C3 _W , C4 _W , D1 _W , D2 _W are provided above the output terminal OUTW. It is done.

  In each phase, the diodes D1 and D2 are closest to the output terminal OUT, followed by the capacitors C2 and C3. Even if the resistors R1 and R2 are arranged far away, the increase in the resistance component due to the wiring can be ignored, and the increase in the resistance value does not affect the operation of the snubber circuit. It was.

The above is the configuration of the power conversion device 2.
In the operating state of the power converter 2, the electrolytic capacitor C1 and the power module 4 generate heat. Since the temperature of the center of the power module 4 is highest, the temperature of the center of the substrate 20 tends to increase due to the influence of the power module 4. On the other hand, according to the power conversion device 2 of FIGS. 2A and 2B, by disposing the plurality of electrolytic capacitors C1 around the center of the substrate 20 where the heat concentration of the power module 4 occurs, The thermal interaction between the electrolytic capacitor C1 and the power module 4 can be reduced.

  Further, since the components of the snubber circuit 8 having a height lower than that of the electrolytic capacitor C1 are arranged in the region surrounded by the electrolytic capacitor C1, the upper part of the components of the snubber circuit 8 is used as an air flow path. The heat of the electrolytic capacitor C1 can be effectively released. As a result, while the noise and surge countermeasures by the electrolytic capacitor C1 and the snubber circuit 8 are maintained, the temperature of the electrolytic capacitor C1 and the power module 4 can be prevented from excessively rising, and the power module 4 and the electrolytic capacitor C1 can be used. The life of the parts can be extended.

  The air heated by the power module 4 and the electrolytic capacitor C1 flows from low to high. In the present embodiment, since the clearance 21 is provided in the direction perpendicular to the ground, there is an advantage that the heated air can be efficiently exhausted upward along the clearance 21.

  FIGS. 3A and 3B are diagrams showing the configuration of the power conversion device 2a according to the first modification. Fig.3 (a) is a perspective view of the power converter device 2a, FIG.3 (b) is a side view of the power converter device 2a.

  Similar to the power conversion device 2 in FIGS. 2A and 2B, the power conversion device 2a has the power module 4 mounted on the first surface S1 of the substrate 20, and the gate drive circuit 6 on the second surface S2. Components of the electrolytic capacitor C1 and the snubber circuit 8 are mounted.

  Further, in the power conversion device 2a, the plurality of electrolytic capacitors C1 are arranged with two regions 23 and 25 so as to have a clearance 21 in the center of the substrate 20. Further, the clearance 21 is provided along the direction perpendicular to the ground in the actual use state.

  Further, each electrolytic capacitor C1 is arranged so that another electrolytic capacitor is not adjacent in at least one of the four directions (up and down, left and right). In the power converter 2a, the electrolytic capacitors C1 are arranged in a line on a straight line in each region.

  The components of the snubber circuit 8 are arranged in a hatched region 27 surrounded by a plurality of electrolytic capacitors C1. The arrangement of the components of the snubber circuit 8 in the region 27 may be the same as that shown in FIG.

  According to the power conversion device 2a according to the modification shown in FIGS. 3A and 3B, the same effects as those of the power conversion device 2 in FIGS. 2A and 2B can be obtained. Note that FIG. 3 illustrates the case where the plurality of electrolytic capacitors C1 are arranged in two rows with the clearance 21 therebetween, but may be arranged in three or more rows.

  FIGS. 4A and 4B are diagrams illustrating the configuration of the power conversion device 2b according to the second modification. Fig.4 (a) is a perspective view of the power converter device 2b, FIG.4 (b) is a side view of the power converter device 2b.

  Similar to the power conversion device 2 of FIGS. 2A and 2B or the power conversion device 2a of FIGS. 3A and 3B, the power conversion device 2b has a power module on the first surface S1 of the substrate 20. 4 is mounted, and components of the gate drive circuit 6, the electrolytic capacitor C1, and the snubber circuit 8 are mounted on the second surface S2.

  In the power conversion device 2b, the plurality of electrolytic capacitors C1 are arranged in a staggered manner. The components of the snubber circuit 8 are arranged in a region 27 surrounded by the electrolytic capacitor C1.

  Looking carefully at FIG. 4A, the plurality of electrolytic capacitors C <b> 1 are arranged in two regions 23 and 25 so as to have a clearance 21 a at the center of the substrate 20. The region 23 is divided into two regions 23a and 23b by the clearance 21b, and the region 25 is divided into two regions 25a and 25b by the clearance 21c. In this modification, it can be said that the clearances 21a to 21c are provided in an oblique direction. Further, in the regions 23a and 25a, the plurality of electrolytic capacitors C1 are common to the power conversion device 2a of FIG. 3A in that they are arranged in a line along the clearance.

  The components of the snubber circuit 8 are arranged in a hatched region 27 surrounded by a plurality of electrolytic capacitors C1.

  The effects similar to those of the power conversion device 2 shown in FIGS. 2A and 2B can be obtained by the power conversion device 2b shown in FIGS. 4A and 4B.

  In the above, this invention was demonstrated based on the Example. It will be understood by those skilled in the art that the present invention is not limited to the above-described embodiment, and various design changes are possible, various modifications are possible, and such modifications are within the scope of the present invention. By the way.

2 ... Power converter, M1, M2 ... Power transistor, 4 ... Power module, 6 ... Gate drive circuit, 8 ... Snubber circuit, 10 ... Heat sink, LP ... Upper power line, LN ... Lower power line, 20 ... Substrate, 21 ... Clearance, C1 ... Electrolytic capacitor, S1 ... First surface, S2 ... Second surface.

Claims (5)

A power converter for supplying power to a load,
An upper power line and a lower power line;
A plurality of electrolytic capacitors provided in parallel between the upper power line and the lower power line,
At least one power provided between the upper power supply terminal and the lower power supply terminal, and having an upper power supply terminal and a lower power supply terminal electrically connected to the upper power supply line and the lower power supply line, respectively. A power module with a built-in transistor;
A gate drive circuit for driving the at least one power transistor;
A snubber circuit electrically connected to the upper power line and the lower power line;
A substrate on which the power module is mounted on the first surface and the gate drive circuit, the plurality of electrolytic capacitors, and the components of the snubber circuit are mounted on the second surface;
With
The plurality of electrolytic capacitors are arranged in at least two regions so as to have a clearance at the center of the substrate,
The power conversion device, wherein the snubber circuit components are arranged in a region surrounded by the plurality of electrolytic capacitors. The substrate forms a plane perpendicular to the ground in actual use,
The power converter according to claim 1, wherein the clearance is provided along a direction perpendicular to the ground.   3. The power conversion device according to claim 1, wherein each electrolytic capacitor is arranged so that another electrolytic capacitor is not adjacent in at least one of the four directions. 4.   4. The power conversion device according to claim 1, wherein the electrolytic capacitors are arranged in a straight line in each region. 5. A power converter for supplying power to a load,
An upper power line and a lower power line;
A plurality of electrolytic capacitors provided in parallel between the upper power line and the lower power line,
At least one power provided between the upper power supply terminal and the lower power supply terminal, and having an upper power supply terminal and a lower power supply terminal electrically connected to the upper power supply line and the lower power supply line, respectively. A power module with a built-in transistor;
A gate drive circuit for driving the at least one power transistor;
A snubber circuit electrically connected to the upper power line and the lower power line;
A substrate on which the power module is mounted on the first surface and the gate drive circuit, the plurality of electrolytic capacitors, and the components of the snubber circuit are mounted on the second surface;
With
Arranging the plurality of electrolytic capacitors in a staggered manner,
The power conversion device, wherein the snubber circuit components are arranged in a region surrounded by the plurality of electrolytic capacitors.

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