JPH11121690A - Power circuit module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power circuit module for electric vehicles, which has a reduced total wt. and space and is superior in cooling, reliability and replacement properties. SOLUTION: This module comprises a first and second circuits 6, 2 formed as separate module units to which high currents are fed separately from a high-voltage battery. The first circuit module 6 has a cooling board (heat sink and heat-conducting member) 602 laminated on and integrated with a cooling board 201 of the second circuit module 2, thereby minimizing the thermal conductivity resistance between both the cooling boards 602, 201, one of which functions as an additional cooling board for suppressing the temp. rise, when one cooling board is more energized than the other board.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a power circuit module, and more particularly to a power circuit module applied to an electric vehicle.

[0002]

2. Description of the Related Art In a conventional hybrid electric vehicle in which power is supplied from a generator driven by an internal combustion engine to a high-voltage (for example, 300 V) main battery and a running motor, an engine starting motor supplied from the main battery supplies power. The internal combustion engine is started, and the above generator or the like can be used as a motor for starting the internal combustion engine.

Japanese Patent Application Laid-Open No. Sho 62-173901 discloses a DC-DC converter for supplying power to an auxiliary machine (hereinafter referred to as a DC-DC converter).
(Also referred to as a module) to supply power to an auxiliary battery dedicated to driving the auxiliary machine. By providing the auxiliary battery in this way, it is possible to supply a high voltage to the traveling motor as compared with an auxiliary device which is normally supplied at a low voltage, so that effects such as loss reduction and downsizing of the device can be realized. There is a benefit that a power supply voltage with small voltage fluctuation can be applied to the auxiliary equipment.

FIG. 7 shows a conventional example of a power circuit for an electric vehicle employing this type of auxiliary battery charging system. 1 is a main battery, 260 is a DC-DC converter and DC-AC
An all-in-one module incorporating an inverter, 3 is an auxiliary battery, 4 is an auxiliary machine, 5 is an auxiliary battery charge command switch, and 7 is a running motor.

In FIG. 7, a high-voltage main battery 1 is supplied with power by an all-in-one module 260 through power cables 800 and 900 with insulating coating. Another conventional example is shown in FIG.
1 is a main battery, 200 is a DC-DC converter module, 3 is an auxiliary battery, 4 is an auxiliary machine, 5 is an auxiliary battery charging command switch, 600 is a DC-AC inverter module, and 7 is a running battery. It is a motor.

In FIG. 8, a high-voltage main battery 1 and DC-A
Terminal blocks 1000 and 110 in the middle of the insulated power cables 800 and 900 connecting the C inverter module 600.
0 from the terminal block.
0 and 1300 are branched to supply power to the DC-DC converter module 200. FIG. 9 shows another conventional example.

This conventional example is different from the conventional example shown in FIG. 8 in that the terminal blocks 1000 and 1100 are omitted, and the DC-DC converter module 200 is directly supplied with power from both ends of the main battery 1 by means of insulated power cables 1200 and 1300. Have been.

[0008]

[Problems to be solved by the invention] However, in each of the conventional electric vehicle power circuits described above, the main battery 1
Due to the fact that the amount of current supplied to the auxiliary battery 3 and the traveling motor 7 is extremely large, the following problem arises. In the all-in-one module shown in FIG.
Since both the DC-DC converter and the DC-AC inverter for supplying power to the auxiliary battery 3 are mounted on the insulating substrate on the cooling substrate (heat sink), the overall shape, particularly the planar shape, becomes flat and large, and is mounted on the vehicle. In addition, even if one of the DC-DC converter and the DC-AC inverter breaks down, the all-in-one module 260 is removed and repaired and reinstalled. This has the disadvantage that the entire unit has to be replaced and the trouble and cost of repair are increased.

Therefore, the present inventors mount a DC-AC inverter on the bottom of an aluminum protective case having a heat sink, and mount a DC-DC converter on the inner surface of a cover plate to form a two-story structure. By doing so, we considered reducing the required area. Also, in this case, the DC-DC
It is possible that the converter can be replaced and the DC-AC inverter can be replaced by replacing the box side. However, in such an internal two-story structure, the input line (power supply line) and the output line must be made redundant so that the lid can be removed from the box. It was found that each line had to be accommodated, and a large increase in case volume and weight rather occurred.

Next, the conventional example shown in FIG. 8 requires extra insulation-coated power cables 1200 and 1300 as compared with the all-in-one module shown in FIG. 7, and the weight, cost and resistance loss are correspondingly large. Problem, DC-DC
Since the internal heat generation of the converter module 200 and the DC-AC inverter module 600 is large, there is a serious problem that their cooling systems are complicated and large. In addition, a terminal box has to be separately provided at a position where the terminal blocks 1000 and 1100 are provided, and the required space, the weight and the cost for the installation of the terminal box, and the trouble of wiring connection are increased.

[0011] Next, in the conventional example shown in FIG. 9, compared with the conventional example shown in FIG.
The terminal 0 is connected to the terminals of both ends of the main battery 1 at the same time as the terminals of the insulated power cables 800 and 900, so that there is an advantage that the terminal box can be omitted. It has to be extended, causing a problem that the weight, wiring space and cost are greatly increased.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a power circuit module that can reduce the overall weight and space, and is excellent in cooling performance, reliability, and exchangeability. Since the present invention is particularly suitable for a power circuit module used as a DC-AC inverter and a DC-DC converter for an electric vehicle, the present invention can reduce the total weight and space, and can provide cooling performance. Another object of the present invention is to provide a power circuit module for an electric vehicle having excellent reliability and exchangeability.

[0013]

According to the configuration of the power circuit module of the present invention, the first circuit section and the second circuit section each supplied with a high voltage and large current from the high voltage battery are separately modularized. You. In this configuration, in particular, the cooling board (heat sink and heat transfer member) of the first circuit unit module
And the cooling board (heat sink and heat transfer member) of the second circuit unit module are integrally joined in a state of being superposed.

With this arrangement, the heat transfer resistance between the two cooling boards is minimized, and when one of the heat generation is more dominant than that of the other, the other cooling board is provided with an additional circuit for the heat generation dominant circuit portion. Function as a cooling substrate, and its temperature rise can be suppressed. In addition, when a special forced cooling structure such as water cooling or forced air is provided on one of the cooling boards, this can be achieved only by natural cooling without providing a special forced cooling structure on the other cooling board. Cooling can be made much better.

Further, since these two modules for supplying power to different loads can be separated from each other, attachment / detachment or replacement for repair is greatly simplified as compared with the all-in-one module. Furthermore, in the power circuit module of the present configuration, the through-type connection conductor is provided in the communication hole provided in each of the two cooling boards which are in close contact with each other so as to be electrically insulated from the cooling board. As compared with the conventional example described above, the configuration is simplified, and the power supply line wiring length can be reduced and the resistance loss can be reduced.

This will be described in more detail. First, if the internal power supply lines (usually busbars) of both modules are connected to each other using the above-mentioned through-type connection conductor, the insulation-covered power cable may be such that the high-voltage battery is supplied to one of the modules by the insulation-covered power cable. In addition, the cost of an insulated power cable can be reduced. That is, in the conventional configuration shown in FIGS. 7 and 8, a pair of power terminals and terminal blocks 1000 and 11 of the insulated power cables 1200 and 1300 and the DC-DC converter module 200 are provided.
00 can be omitted, and weight, space, and cost can be saved. Of course, in the present configuration, a penetrating connection conductor is required as an alternative to the above omission, but it can also be configured by simply extending the bus bar, for example, since it penetrates both cooling substrates that are the contact portions of both. The length is also extremely short, so that the routing of the insulated power cable is not a problem.

Further, since the communication hole in this configuration can be cut off and separated from the outside substantially, it is not necessary to add a pipe or the like, and it is easy to improve the waterproofness as compared with the conventional drawing of the insulation-coated power cable. Can be realized.
According to the second aspect of the present invention, the power circuit module according to the first aspect further includes an electrically insulating penetrating terminal block fixed to the cooling board on the first circuit portion side and penetrating the communication hole, The penetrating connection conductor is surrounded and supported by the penetrating terminal block with both ends exposed to both internal spaces of the case, and one end is connected to a power supply line (for example, a bus bar) of the first circuit portion and the other end is connected to the power supply line. It is connected to a power supply line (for example, bus bar) of the second circuit section. That is, the through-type terminal block with the through-type connection conductor has a unique terminal block structure having a required number of connection terminals short-circuited by the internal through-type connection conductor at both ends. This makes it easy to support, assemble, and separate the through connection conductor.

According to a third aspect of the present invention, in the power circuit module according to the second aspect, the case on the second circuit portion side (the case on which the through-type terminal block is not fixed) is further provided.
An outer peripheral wall surrounding the communication hole, the through terminal block and the insulating substrate;
The communication terminal includes a partition wall that separates the communication hole and the through-type terminal block from the insulating substrate, a first lid plate that seals the through-type terminal block, and a second lid plate that seals the insulating substrate.

With this configuration, when the two circuit modules are separated from each other, the opening of the case of the second circuit section is entirely opened without exposing the inside of the second circuit section.
Since only the small first cover plate needs to be removed, both modules can be separated, so that there is an effect that the work safety and the environmental resistance are particularly excellent. According to the configuration described in claim 4, in the power circuit module according to any one of claims 1 to 3, the case on the first circuit portion side is further liquid-cooled, and the case on the second circuit portion side is not liquid-cooled. . In this way, both modules can be cooled well without having to attach a liquid cooling structure to each module, and the second circuit module having no liquid cooling structure can be easily attached and detached. The effect of being excellent in exchangeability can be obtained.

According to a fifth aspect of the present invention, in the power circuit module according to any one of the first to fourth aspects, further formed between the communication hole and the through-type terminal block to communicate the internal space of both cases. With a breathing hole. In this way, even if the air temperature in one case changes more significantly than the air temperature in the other case and expands or contracts more remarkably, the internal spaces of both cases communicate with each other. The air expanded in the internal space of the will flow through the breathing hole into the other relatively cool internal space and will be cooled,
Eventually, it can be seen that the pressure change in both internal spaces is reduced by the presence of the breathing hole.

When the power supply cable has a communication hole or a screw hole, it is difficult to make the internal space of the case highly airtight. Therefore, when the internal pressure changes, the internal space changes accordingly. Air movement (breathing) occurs between the air and the outside air, and moisture, moisture, corrosive gas, and the like enter the internal space from the outside. This problem is counteracted by maintaining the breathing hole.

According to a sixth aspect of the present invention, in the power circuit module according to any one of the first to fifth aspects, the first circuit portion further includes a driving motor driving D for an electric vehicle.
The second circuit unit comprises a DC-DC converter module for charging an auxiliary battery for an electric vehicle. The main battery of an electric vehicle is
The auxiliary battery is charged through the DC-DC converter module, and the driving motor is controlled through a DC-AC inverter module separate from the DC-DC converter module.

[0023] Both of these modules do not generate heat at the same time, so that one of the two can act as a mere heat sink and radiator, which is very advantageous. According to the configuration described in claim 7, in the power circuit module according to any one of claims 1 to 6, the communication hole is further sealed by an O-ring interposed between the two cooling boards. -Effect can be achieved.

According to an eighth aspect of the present invention, in the power circuit module according to any one of the first to seventh aspects, both cooling boards also serve as low-voltage side internal power supply lines, so that the configuration is simplified. Can be. According to a ninth aspect of the present invention, in the power circuit module according to the fourth aspect, the case on the first circuit portion side is located at a portion in contact with the case on the second circuit portion side to form a coolant passage. Have.

With this arrangement, the heat transfer resistance from the coolant passage to the case on the side of the second circuit portion is reduced.
This is effective in suppressing the temperature rise of the second circuit portion where the liquid is not liquid cooled.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the following examples.

[0027]

Embodiment 1 An embodiment in which the power converter of the present invention is applied to a drive circuit of an electric vehicle will be described with reference to the drawings. (Explanation of Drive Circuit of Electric Vehicle) The circuit of the electric vehicle of this embodiment will be described with reference to the block diagram shown in FIG.

The main battery 1 supplies power to a DC-DC converter 2 and a DC-AC inverter module 6 which constitute a power converter of the present embodiment, respectively.
The converter 2 supplies a low-voltage DC power supply voltage to the auxiliary battery 3 and the various auxiliary machines 4 for a vehicle. Reference numeral 5 denotes a manual switch for instructing the DC-DC converter module 2 to perform an auxiliary battery charging operation, and a DC-AC inverter module.
The motor 6 supplies power to a three-phase AC motor 7 for running the vehicle.

(DC-DC Converter 2) The DC-DC converter 2 will be described with reference to a circuit diagram shown in FIG. Reference numeral 5 denotes a charge command switch for applying the voltage from the auxiliary battery 3 to the DC-DC converter module 2. The H-bridge circuit 3A includes N-channel MOSFET high-side switches 31, 32 and N-channel MOSFETs.
Low-side switches 33 and 34 and diodes D connected in anti-parallel to these switches 31 to 34 individually.
Consists of

The high-side switch 31 and the low-side switch 33 connected in series constitute a first phase switch circuit, and the high-side switch 32 and the low-side switch 34 connected in series constitute a second phase switch circuit. These two-phase switch circuits convert DC power supplied from the main battery 1 into single-phase AC power.
The output terminal of the first phase switch circuit, which is the connection point between the high side switch 31 and the low side switch 33, and the output terminal of the second phase switch circuit, which is the connection point between the high side switch 32 and the low side switch 34, Connected to the primary coil of the transformer 22 for the
The voltage of the secondary coil of No. 2 is rectified by diodes 23 and 24 and then smoothed by a smoothing circuit including a reactor 25 and a capacitor 26 to charge the auxiliary battery 3.

Reference numeral 27 denotes a current sensor for detecting a primary current of the transformer 22, and the detected current is used as the control circuit 2
8 is output. The control circuit 28 is operated by being supplied with a constant power supply voltage from a constant voltage power supply 29 supplied from the main battery 1, and based on the voltage of the auxiliary battery 3 and the primary current of the transformer 22, the control circuit 28 has a predetermined value. Thus, the MOSFETs 31 to 34 are intermittently controlled through the drive circuit 30.

Reference numerals 40 and 41 denote a pair of DC input terminals (power supply terminals) of the DC-DC converter module 2 connected to both ends of the main battery 1. DC input terminals 40 and 41 are internal busbars 42 and 41, respectively. Power is supplied to the above-described H-bridge circuit 3A through 43. Reference numeral 44 denotes a capacitor for removing ripples, and reference numerals 45 and 46 denote terminals for outputting low-voltage DC power to the auxiliary battery 3.

(DC-AC inverter module 6) D
The C-AC inverter module 6 will be described with reference to the circuit diagram shown in FIG. 61 to 66 are IGBTs,
63 is a high side switch, and 64 to 66 are low side switches. The high-side switch 61 and the low-side switch 64 connected in series constitute a first phase switch circuit, the high-side switch 62 and the low-side switch 65 connected in series constitute a second phase switch circuit, The high-side switch 63 and the low-side switch 66 connected in series constitute a third phase switch circuit, and each phase switch circuit is connected to the main battery 1.
Powered by D is a flywheel diode connected in parallel with the IGBTs 36 to 41, for supplying a return current to the three-phase AC motor 7, which is an inductive load. The output terminal of each phase switch circuit is individually connected to each terminal of the three-phase AC motor 7.

Reference numerals 67 and 68 denote current sensors for detecting the first and second output currents. A controller 69 controls the IGBTs 61 to 66 on and off based on these output currents and the motor control signal received from the accelerator sensor 50. Then, the three-phase AC motor 7 is rotated at the commanded rotation speed. (DC-DC converter module 2 and DC-AC
Structure of Inverter Module 6) DC-DC Converter Module 2 and DC-AC Inverter Module 6
Will be described with reference to FIG.

Both ends of the main battery 1 are connected to DC input terminals (power terminals) 16, 1 of the DC-AC inverter module 6.
7 are individually connected to branch terminals 70 and 71 of terminals of bus bars 8 and 9 disposed inside the DC-AC inverter module 6. The bus bars 8 and 9 supply power to a DC-AC inverter circuit (not shown in FIG. 1), and the branch terminals 70 and 71 thereof are connected to the DC-DC converter module 2 through the through connection conductors 14 and 15 of the through terminal block. Are connected to DC input terminals (power supply terminals) 16 and 17 comprising terminals of busbars 42 and 43 disposed inside.

FIG. 4 is a longitudinal sectional view of both modules 2 and 6. The DC-DC converter module 2 has a case 201 having an upper end opening.
a, an outer peripheral wall 201b, and a partition 201c. The upper end opening of the case 201 has a first lid plate 202 and a second lid plate 2 each made of an aluminum plate.
03 is shielded.

The partition 201c divides the internal space of the case 201 into a circuit room 204 and a connection room 205, and the first cover plate 202 seals the connection room 205 and the second cover plate 2
Numeral 03 seals the circuit room 204. The bottom plate part 201a has a through hole 206 communicating with the connection chamber 205. An insulating substrate 207 is joined to the bottom plate 201a facing the circuit chamber 204, and a circuit element 208 forming a DC-DC converter shown in FIG. 2 is mounted on the insulating substrate 207.

The DC-AC inverter module 6 has a case 601 having an upper end opening, and the case 601 is formed of an aluminum molded product having a bottom plate 601a and an outer peripheral wall 601b. The upper end opening of the case 601 is shielded by fastening a lid plate 602, which is an aluminum plate, so that the case 6
01 is shielded from the internal space s. The cover plate 602 has a through hole 606 communicating with the connection chamber 205 of the module 2. An insulating substrate 607 is joined to the cover plate 602, and a circuit element 608 forming a DC-AC inverter shown in FIG. 3 is mounted on the insulating substrate 607.

Numeral 609 denotes a cooling water passage having openings at both ends formed in the bottom plate portion 601a. Both ends of the cooling water passage 609 are connected to a hose 611 by a connector pipe 610, and the cooling water circulates. I have. 700 is the case 201
And a bolt 701 for fastening the cover plate 602 to the case 601, and a bolt 701 for fastening the cover plates 202 and 203 to the case 201.

A bolt 702 is provided on the inner surface of the lid plate 602.
The through-type terminal block is an electrically-insulating resin molded product, and the through-type terminal block 800 has through-type connecting conductors 14 and 15 formed of a pair of copper plates vertically embedded therein. Through-type connecting conductor 1 exposed from upper and lower end surfaces of through-type terminal block 800
Screw holes are formed in the upper and lower ends of 4 and 15, and busbars 8, 9 and 42 and 43 are fastened to these screw holes.

FIG. 5 is an enlarged partial perspective view of the vicinity of the connection chamber 205. However, the first cover plate 202 is omitted. The assembly of this device is described below. Decomposition may be performed in the reverse order. First, the circuit element 208 and the bus bars 42 and 43 are mounted on the case 201, and the penetrating terminal block 800, the circuit element 608 and the bus bar 8 are mounted on the cover plate 602.
9 are mounted, and the bus bars 8 and 9 are fastened to the through connection conductors 801 and 802 of the through terminal block 800. Further, the second cover plate 203 is fastened to the case 201.

Next, after the cover plate 602 and the case 201 are fastened to the case 601 with the bolt 700, the busbar-4
2, 43 are the through connection conductors 80 of the through terminal block 800
1, 802, and then the first cover plate 202 is fastened to the case 201. When the cooling water flows through the cooling water passage 609, the cooling water is entirely made of aluminum.
02, the circuit element 208 is cooled well through the case 201. 900 is a breathing hole. Reference numeral 901 denotes an O-ring for sealing the communication hole. (Modification 1) In the above embodiment, the penetrating terminal block 800 has the pair of penetrating connection conductors 801 and 802.
It is also possible to omit the through-type connection conductor 802 while leaving only the through-type connection conductor 801 on the positive potential side. That is, instead of the through-type connection conductor 802 on the negative side, the case 2
01 and the cover plate 602 can be used. (Modification 2) Another modification will be described with reference to FIG. However, components having the same main functions as those of the above embodiment are denoted by the same reference numerals.

In this modification, the case 601 of the module 6 is opened at the lower end, and the internal space s is closed by the lower cover plate 6020. A groove 609 having an upper opening is formed in the bottom plate 601a on the upper side of the case 601.
The groove 609 is shielded by fastening the cover plate 602, and the groove 609 is used as a cooling water passage. This facilitates the formation of a complicated curved pipe-shaped cooling water passage, and improves the cooling performance of the module 2 by the cooling water passage 609.

Note that the cover plate 602 is omitted and the case 20 is omitted.
The groove 609 may be shielded by 1 to form a cooling water passage.

[Brief description of the drawings]

FIG. 1 is a DC-AC inverter module and a DC-DC for an electric vehicle which constitute a power circuit module of the present invention.
FIG. 3 is a circuit diagram showing a converter module.

FIG. 2 is a circuit diagram of the DC-DC converter module 2 of FIG.

FIG. 3 is a circuit diagram of the DC-AC inverter module of FIG.

FIG. 4 is a longitudinal sectional view of the power circuit module of FIG. 1;

FIG. 5 is an enlarged partial perspective view in the vicinity of a connection chamber 205 in FIG.

FIG. 6 is a longitudinal sectional view showing a modification of the power circuit module of FIG. 1;

FIG. 7 is a circuit diagram showing a DC-AC inverter module and a DC-DC converter module for an electric vehicle, which constitute conventional power circuit modules.

FIG. 8 is a circuit diagram showing a DC-AC inverter module and a DC-DC converter module for an electric vehicle, which constitute conventional power circuit modules.

FIG. 9 is a circuit diagram showing a DC-AC inverter module and a DC-DC converter module for an electric vehicle which constitute conventional power circuit modules.

[Explanation of symbols]

1 is a main battery (high voltage battery), 2 is a DC-DC converter module (first circuit section), 6 is a DC-AC inverter module (second circuit section), 201 is a case (cooling board), 202 Is a second lid plate, 203 is a second lid plate,
601 is a case, 602 is a lid plate (cooling substrate), 207,
607 is an insulating substrate, 8, 9, 42 and 43 are busbars (internal power supply lines), 206 and 606 are communication holes, 800 is a through terminal block, 801 and 802 are through connection conductors, 900
Is a breathing hole, and 901 is an O-ring.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Nobuyuki Taki 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (9)

[Claims] 1. A first circuit section and a second circuit section which are supplied in parallel from a large-capacity high-voltage battery and output to different power devices, wherein both circuit sections are each formed of a metal cooling board at least one surface. Case and
A power circuit module including an insulating substrate mounted with a circuit element and joined to an inner surface of the cooling substrate, and a pair of power supply lines housed in the case and supplying power to the circuit element, wherein the outer surfaces are separated from each other. A through hole that penetrates through the two cooling boards and is connected to the internal space of the two cases, and a through-type connection that connects the internal power supply lines of the two circuit portions through the through hole; A power circuit module comprising: a conductor. 2. The power circuit module according to claim 1, further comprising an electrically insulating penetrating terminal block fixed to the cooling board on the first circuit portion side and penetrating the communication hole. The conductor is surrounded and supported by the penetrating terminal block with both ends exposed to both internal spaces of the case, and one end is connected to the internal power supply line of the first circuit portion and the other end is connected to the second circuit. A power circuit module connected to an internal power supply line of the unit. 3. The power circuit module according to claim 2, wherein the case on the second circuit portion side includes an outer peripheral wall surrounding the penetrating terminal block and the insulating substrate, and the penetrating terminal block and the insulating substrate. And a first partition for sealing the through-type terminal block.
A power circuit module, comprising: a lid plate described above; and a second lid plate that seals the insulating substrate. 4. The power circuit module according to claim 1, wherein the case on the first circuit part side is liquid-cooled, and the case on the second circuit part side is not liquid-cooled. Power circuit module. 5. The power circuit module according to claim 1, further comprising a breathing hole formed between the communication hole and the penetrating terminal block and communicating the internal spaces of the two cases. A power circuit module, comprising: 6. A power circuit module according to claim 1, wherein said first circuit portion is a drive motor for driving an electric vehicle.
A power circuit module comprising a C-AC inverter module, wherein the second circuit section comprises a DC-DC converter module for charging an auxiliary battery for an electric vehicle. 7. The power circuit according to claim 1, wherein the communication hole is sealed by an O-ring interposed between the cooling boards. module. 8. The power circuit module according to claim 1, wherein the two cooling boards are in contact with each other so as to be electrically conductive, and a low-voltage side internal power supply line of the two internal power supply lines is connected to the cooling board. A power circuit module, which also serves as a power circuit module. 9. The power circuit module according to claim 4, wherein the case on the first circuit portion side has a coolant passage located at a portion in contact with the case on the second circuit portion side. Characteristic power circuit module.