JP6219442B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device used for converting DC power to AC power, or for converting AC power to DC power, and more particularly, to efficiently generate heat generated inside a casing that houses electrical components of the power conversion device. The present invention relates to a power converter that can dissipate heat well.

  Generally, a power conversion device includes a smoothing capacitor module that receives DC power from a DC power source, an inverter circuit that receives DC power from the capacitor module and generates AC power, and a control circuit for controlling the inverter circuit. .

  AC power obtained by the power converter is supplied to an electric motor (for example, a three-phase synchronous motor), and the electric motor generates rotational torque in accordance with the supplied AC power. Moreover, the electric motor generally has a function as a generator, and a rotational force is supplied from the outside to the electric motor to generate AC power.

  As described above, the power conversion device often has a function of converting AC power into DC power, and the AC power generated by the electric motor is converted into DC power. Conversion from DC power to AC power or conversion from AC power to DC power is controlled by a control device.

  For example, when the electric motor is a synchronous motor, control related to power conversion can be performed by controlling the phase of the rotating magnetic field generated by the stator with respect to the magnetic pole position of the rotor of the synchronous motor. An example of a power converter is disclosed in Japanese Patent Application Laid-Open No. 2011-217548 (Patent Document 1).

  The power conversion device is mounted on, for example, a hybrid vehicle, and generates AC power to be supplied to an electric motor that receives DC power from a secondary battery mounted on the vehicle and generates rotational torque for traveling. Further, during regenerative braking operation such as deceleration operation of an automobile, the electric motor is rotated by the rotation of wheels to generate AC power in order to generate braking force, and the generated AC power is converted into DC power by a power converter. It is stored in the next battery and used again as electric power for traveling.

JP 2011-217548 A

  Many electronic components, for example, insulated gate bipolar transistors with a large amount of heat generation, are used inside the casing of the power converter as described above, and the phenomenon that the inside of the casing becomes a high temperature environment due to the heat generated from these electronic components. is there. Furthermore, the power converter is connected to a conductive wire that is electrically connected to the motor and has good heat transfer, and the heat of the motor enters the bus bar of the power converter through this conductive wire, and this heat is transferred to the inverter circuit unit. In some cases, there is a phenomenon in which the temperature inside the casing of the power conversion device is increased by entering the capacitor module.

When connecting the power module and the capacitor module, which are the main components, with a metal conductor, it is common to use a copper bus bar because of the electrical thermal resistance. The bus bar is preferably shorter from the viewpoint of low inductance. On the other hand, when the bus bar is short, the heat transfer path between the power module and the capacitor module is shortened, and the heat of the power module is easily transferred to the capacitor module, which may reduce the reliability of the capacitor module.

An object of the present invention is to provide a power converter having a low inductance and a high cooling, which is compatible with a trade-off between a low inductance and a thermal effect reduction.

The feature of the present invention resides in that a capacitor board that protrudes from the opening of the capacitor module is arranged toward the power module side so as to shorten the electrical wiring , and a cooling board that dissipates heat from the power module terminal is provided.

According to the present invention, it is possible to realize a power converter having low inductance and high cooling.

1 is a system diagram showing a system of a hybrid vehicle. It is a circuit diagram which shows the structure of the electric circuit shown in FIG. It is an external appearance perspective view which shows the external structure of the power converter device in one Example of this invention. It is the disassembled perspective view which decomposed | disassembled the component of the power converter device shown in FIG. 3, and was seen from the outside. FIG. 4 is an external perspective view of the power converter shown in FIG. 3 with an upper cover and a driver circuit board removed. It is an external appearance perspective view of the newly developed capacitor module used for one Example of this invention. It is the figure which showed the newly developed cooling board used for one Example of this invention, (a) is the external appearance perspective view seen from upper part diagonal, (b) is the front view, (c) is the front It is AA sectional drawing of a figure. It is the external appearance perspective view which looked at the cooling plate shown in FIG. 7 from upper part diagonally. It is the external appearance perspective view which looked at the back surface of the newly developed cooling board used for one Example of this invention from upper part diagonally. It is a front view of the state which removed the upper cover and driver circuit board of the power converter device which become one Example of this invention. It is a surface view of the state which removed the cooling board with the power converter device shown in FIG. It is sectional drawing which showed the BB cross section of the power converter device shown in FIG.

  Next, an embodiment according to the present invention will be described with reference to the drawings. FIG. 1 illustrates a power conversion apparatus targeted by the present invention for a so-called hybrid type vehicle that travels using both an internal combustion engine and an electric motor. It is a system diagram at the time of applying.

  The power conversion device according to the present invention can be applied not only to a hybrid vehicle but also to a so-called electric vehicle that runs only by an electric motor, and power conversion for driving an electric motor used in a general industrial machine. Although it can be used as a device, a power conversion device applied to a hybrid vehicle will be described as a representative example.

  FIG. 1 is a diagram showing a control block of a hybrid vehicle, and an internal combustion engine EGN and a motor generator MG are power sources that generate driving torque of the vehicle. Motor generator MG not only generates rotational torque, but also has a function of converting mechanical energy (rotational force) applied to motor generator MG from the outside into electric power.

  The motor generator MG is, for example, a synchronous motor / generator or an induction motor / generator, and operates as a motor or a generator depending on the operation method as described above. When the motor generator MG is mounted on an automobile, it is desirable to obtain a small and high output, and a permanent magnet type synchronous motor using a magnet such as neodymium is suitable. In addition, the permanent magnet type synchronous motor generates less heat from the rotor than the induction motor, and is excellent for automobiles from this viewpoint.

  The output side of the internal combustion engine EGN is transmitted to the motor generator MG via the power distribution mechanism TSM, and the rotation torque from the power distribution mechanism TSM or the rotation torque generated by the motor generator MG is transmitted to the wheels via the transmission TM and the differential gear DEF. Is transmitted to.

  On the other hand, during regenerative braking operation, rotational torque is transmitted from the wheels to motor generator MG, and AC power is generated based on the transmitted rotational torque. The generated AC power is converted into DC power by the power conversion device 200 as described later, and the high-voltage battery 136 is charged. The charged power is used again as travel energy.

  Next, the power conversion device 200 will be described. The inverter circuit unit 140 is electrically connected to the battery 136 via a DC connector 138, and power is exchanged between the battery 136 and the inverter circuit unit 140.

  When motor generator MG is operated as an electric motor, inverter circuit section 140 generates AC power based on DC power supplied from battery 136 via DC connector 138, and supplies it to motor generator MG via AC terminal 188. To do. The configuration including motor generator MG and inverter circuit unit 140 operates as an electric / power generation unit.

  The electric / power generation unit may be operated as an electric motor or a generator according to an operation state, or may be operated by using them properly. In the present embodiment, the vehicle can be driven only by the power of the motor generator MG by operating the electric / power generation unit as an electric unit by the electric power of the battery 136. Furthermore, in the present embodiment, the battery 136 can be charged by operating the electric / power generation unit as the power generation unit by the power of the internal combustion engine EGN or the power from the wheels to generate power.

  The power conversion device 200 includes a capacitor module 500 for smoothing DC power supplied to the inverter circuit unit 140.

  The power conversion device 200 includes a communication connector 21 for receiving a command from a host control device or transmitting data representing a state to the host control device. A control circuit unit 172 calculates a control amount of the motor generator MG based on a command input from the connector 21.

  Further, whether to operate as an electric motor or a generator is calculated, a control pulse is generated based on the calculation result, and the control pulse is supplied to the driver circuit 174. Based on this control pulse, the driver circuit 174 generates a drive pulse for controlling the inverter circuit unit 140.

  The inverter circuit unit 140, the control circuit unit 172, the driver circuit 174, the capacitor module 500, and the like constituting the power conversion device 200 are housed in an aluminum alloy casing as will be described later, and by a cooling medium (for example, cooling water). It is configured to be cooled.

  Next, the circuit configuration of the inverter circuit unit 140 will be described with reference to FIG. 2. An insulated gate bipolar transistor is used as a semiconductor element, which is hereinafter abbreviated as IGBT.

  The inverter circuit unit 140 includes U-phase and V-phase of AC power to be output from the power module 150 of the upper and lower arms including the IGBT 328 and the diode 156 that operate as the upper arm, and the IGBT 330 and the diode 166 that operate as the lower arm. , Corresponding to three phases consisting of W phases.

  In this embodiment, these three phases correspond to the three-phase windings of the armature winding of motor generator MG. The power module 150 of the upper and lower arms of each of the three phases outputs an alternating current from an intermediate electrode 169 that is a middle point portion of the IGBT 328 and the IGBT 330 of the power module 150, and this alternating current passes through the alternating current terminal 159 and the alternating current connector 188. It is connected to an AC bus bar which is an AC power line to generator MG.

  The collector electrode 153 of the IGBT 328 in the upper arm is connected to the capacitor terminal 506 on the positive electrode side of the capacitor module 500 through the positive electrode terminal 157, and the emitter electrode of the IGBT 330 in the lower arm is connected to the capacitor terminal on the negative electrode side of the capacitor module 500 through the negative electrode terminal 158. 504 are electrically connected to each other.

  As described above, the control circuit unit 172 receives a control command from the host control device via the connector 21, and configures the upper arm or the lower arm of each phase power module 150 constituting the inverter circuit unit 140 based on the control command. A control pulse that is a control signal for controlling the IGBT 328 and the IGBT 330 is generated and supplied to the driver circuit 174.

  Based on the control pulse, the driver circuit 174 supplies a drive pulse for controlling the IGBT 328 and the IGBT 330 constituting the upper arm or the lower arm of the power module 150 of each phase to the IGBT 328 and IGBT 330 of each phase.

  The IGBT 328 and the IGBT 330 perform conduction or cutoff operation based on the drive pulse from the driver circuit 174, convert the DC power supplied from the battery 136 into three-phase AC power, and the converted power is supplied to the motor generator MG1. The

  The IGBT 328 includes a collector electrode 153, a signal emitter electrode 155, and a gate electrode 154. The IGBT 330 includes a collector electrode 163, a signal emitter electrode 165, and a gate electrode 164.

  A diode 156 is electrically connected between the collector electrode 153 and the emitter electrode. A diode 166 is electrically connected between the collector electrode 163 and the emitter electrode.

  As the switching power semiconductor element, a metal oxide semiconductor field effect transistor (hereinafter abbreviated as MOSFET) may be used. In this case, the diode 156 and the diode 166 are unnecessary. As a switching power semiconductor element, IGBT is suitable when the DC voltage is relatively high, and MOSFET is suitable when the DC voltage is relatively low.

  The capacitor module 500 includes a plurality of positive electrode side capacitor terminals 506, a plurality of negative electrode side capacitor terminals 504, a positive electrode side power supply terminal 509, and a negative electrode side power supply terminal 508. High voltage DC power from the battery 136 is supplied to the positive power supply terminal 509 and the negative power supply terminal 508 via the DC connector 138, and the plurality of positive capacitor terminals 506 and the plurality of negative capacitors on the capacitor module 500 are provided. The voltage is supplied from the terminal 504 to the inverter circuit unit 140.

  On the other hand, the DC power converted from the AC power by the inverter circuit unit 140 is supplied to the capacitor module 500 from the positive capacitor terminal 506 and the negative capacitor terminal 504, and is connected to the DC connector 138 from the positive power terminal 509 and the negative power terminal 508. Is supplied to the battery 136 and stored in the battery 136.

  The control circuit unit 172 includes a microcomputer (hereinafter, referred to as “microcomputer”) for calculating the switching timing of the IGBT 328 and the IGBT 330. Information input to the microcomputer includes a target torque value required for the motor generator MG, a current value supplied from the upper and lower arm power module 150 to the motor generator MG, and a magnetic pole position of the rotor of the motor generator MG1.

  The target torque value is based on a command signal output from a host controller (not shown), and the current value is detected based on a detection signal from a current sensor. The magnetic pole position is detected based on a detection signal output from a rotating magnetic pole sensor (not shown) such as a resolver provided in motor generator MG1.

  In this embodiment, the case where the current sensor detects a current value of three phases is taken as an example. However, a current value for two phases may be detected, and a current for three phases may be obtained by calculation. good.

  The microcomputer in the control circuit unit 172 calculates the d and q axis current command values of the motor generator MG based on the target torque value, the calculated d and q axis current command values, and the detected d, d and q axis voltage command values are calculated based on the difference from the q axis current value, and the calculated d and q axis voltage command values are calculated based on the detected magnetic pole position. , Converted to W-phase voltage command value.

  The microcomputer generates a pulse-like modulated wave based on a comparison between the fundamental wave (sine wave) and the carrier wave (triangular wave) based on the U-phase, V-phase, and W-phase voltage command values, and the generated modulated wave Is output to the driver circuit 174 as a PWM (pulse width modulation) signal.

  When driving the lower arm, the driver circuit 174 outputs a drive signal obtained by amplifying the PWM signal to the gate electrode of the corresponding IGBT 330 of the lower arm. Further, when driving the upper arm, the driver circuit 174 amplifies the PWM signal after shifting the level of the reference potential of the PWM signal to the level of the reference potential of the upper arm and uses this as a drive signal for the IGBT 328 of the corresponding upper arm. Output to each gate electrode.

  In addition, the control circuit unit 172 performs abnormality detection (overcurrent, overvoltage, overtemperature, etc.) and protects the power module 150 of the upper and lower arms. For this reason, sensing information is input to the control circuit unit 172. For example, information on the current flowing through the emitter electrodes of the IGBTs 328 and IGBTs 330 is input from the signal emitter electrode 155 and the signal emitter electrode 165 of each arm to a corresponding overcurrent detection unit (not shown).

  Thereby, each overcurrent detection part performs an overcurrent detection, and when an overcurrent is detected, the switching operation of the corresponding IGBT 328 and IGBT 330 is stopped, and the corresponding IGBT 328 and IGBT 330 are protected from the overcurrent.

  Information on the temperature of the power module 150 of the upper and lower arms is input to the microcomputer from a temperature sensor (not shown) provided in the power module 150 of the upper and lower arms. In addition, voltage information on the DC positive side of the power module 150 of the upper and lower arms is input to the microcomputer. The microcomputer performs over-temperature detection and over-voltage detection based on the information, and stops switching operations of all the IGBTs 328 and IGBTs 330 when an over-temperature or over-voltage is detected.

  In the power conversion device 200 having such a configuration, as described above, many electronic components, for example, an IGBT having a large calorific value, are often used inside the housing, and the interior of the housing is heated to a high temperature due to heat generated from these electronic components. There is a phenomenon that becomes an environment. Furthermore, a conductive wire that is electrically connected to the electric motor and has good heat transfer is connected, and the heat of the electric motor enters the bus bar of the power conversion device through this conductive wire, and this heat is transmitted to the inverter circuit section and in some cases. There is a phenomenon in which the temperature inside the casing of the power converter is increased as a result of entering the capacitor module.

  As described above, in such a power conversion device, cooling of the power conversion device is extremely important in order to improve power conversion performance. In particular, the DC smoothing capacitor module housed in the casing of the power converter is thermally weak, and in order to ensure its performance, it is required to cool the capacitor module efficiently, and it enters from the outside. It is required to reduce the heat to be generated as much as possible.

  The present invention proposes a technique that meets the demands of either or both of efficiently performing cooling of the capacitor module and minimizing heat entering from the outside.

  Next, the cooling structure and cooling method of the power conversion device, which is a feature of the present invention, will be specifically described with reference to the drawings.

FIG. 3 is an external view of the power conversion device 200. A casing 400 made of metal, for example, an aluminum alloy, is formed of a box-shaped rectangular parallelepiped having a pair of short side walls and long side walls, and has one side surface. A DC connection port 410 for storing a DC terminal and an AC connection port 409 for storing an AC terminal are formed.

A lower cover 404 is fixed to the bottom of the housing 400, and a pipe 406 through which a cooling medium flows in / out is provided in the lower cover 404. The casing 400 houses the capacitor module 500, the inverter circuit unit 140, the control circuit unit 172, the driver circuit 174, and the like.

  4 is an overall configuration diagram in which the power conversion device 200 shown in FIG. 3 is disassembled for each component and shown as a perspective view. FIG. 5 is a diagram when the upper cover and the driver circuit board shown in FIG. 4 are removed. It is a perspective view of this power converter device.

  Then, based on FIG.4 and FIG.5, schematic structure of the power converter device 200 which becomes one Example of this invention is demonstrated, and the cooling structure and cooling method of the power converter device which are the characteristics of this invention are demonstrated in detail after that. .

  4 and 5, reference numeral 400 is a metal (for example, aluminum alloy) housing that houses the components of the power conversion device 200, and a pair of long side walls having a bottom wall portion that is open at the top in the vertical direction. It is formed in a rectangular box shape having a portion 400A and a pair of short side wall portions 400B. The housing 400 is formed with a storage portion 402 for storing the capacitor module 500, a storage portion 403 for storing the power module 150, and the like.

A lower cover 404 is firmly fixed to the lower portion of the bottom wall portion 400C of the casing 400 by a fixing screw 405, and a pipe 406 through which a cooling medium flows in and out is provided in the lower cover 404.

Therefore, the cooling medium flows through the cooling passage formed in the space between the lower cover 404 and the bottom wall portion 400C to cool the inside of the casing 400.

In a position between between one short-side wall portion 400B and the pair of long sides side wall 400A of the housing 400, the bottom wall of the accommodating portion 402 formed therein via a heat dissipation sheet 40 1 capacitor A module 500 is placed. The heat dissipation sheet 40 1 is provided with a heat dissipation function and the insulating function to release the heat of the capacitor module 500 to the bottom wall of the housing 400.

  Next to the capacitor module 500, three storage portions 403 that individually store the three power modules 150 are formed, and the storage portions 403 are opened to a cooling passage between the lower covers 404.

  Therefore, the power module 150 has a liquid-tight configuration by itself, and is specifically sealed with a seal packing or the like between the power module 150 and the storage unit 403. Therefore, the power module 150 is configured to be cooled by directly contacting the cooling medium. Such a configuration is slightly different, but is already known from the above-mentioned Patent Document 1 and the like filed by the present applicant.

  The storage portions 403 of the three power modules 150 are arranged side by side so as to face the other short side wall portion 400B of the casing 400 on the side opposite to the capacitor module 500. Accordingly, the AC terminal 407 and the DC terminal 408 can be accommodated from the same surface on the short side wall portion 400B side.

  The short side wall portion 400B is formed with an AC side storage port 409 in which three AC terminals 407 are stored and a DC side storage port 410 to which one DC terminal 408 is connected. The AC terminal 407 and the power module 150 are connected by a plate-like AC connection bus bar 416. As will be described later, heat entering from the outside through the AC connection bus bar 416 through the conductor is released to the housing 400 side. The configuration is adopted.

  A current sensor 411 and a laminated conductor plate 412 are disposed in a space between the power module 150 and the short side wall portion 400B of the casing 400.

  On top of the capacitor module 500, the power module 150, the current sensor 411, the laminated conductor plate 412, and the like, a cooling board 413, which is a characteristic component of the present invention, is disposed so as to cover them.

  The cooling board 413 is placed on the long and short side wall portions 400 </ b> A and 400 </ b> B of the housing 400 and is firmly fixed to the housing 400 by fixing screws 414. By firmly fixing the casing 400, heat from the capacitor module 500 and heat from the AC connection bus bar 416 are released to the casing 400.

  A heat radiation sheet 415 is interposed between the capacitor module 500 and the cooling board 413 so that the heat of the capacitor module 500 is released to the cooling board 413.

The power between the AC connection bus bar 416 and the cooling board 413 of the module 150 is interposed heat dissipation sheet 417, the AC terminal 40 7 AC connecting motor heat coming flows from the bus bar 416 and the heat radiating sheet 417, Through the cooling board 413.

  Further, the heat from the AC connection bus bar 416 is released to the housing 400 by being firmly fixed to the housing 400 by the fixing screw 414.

  A driver circuit board 418 on which a driver circuit 174 for driving the power module 150 is mounted is disposed on the cooling board 413, and an upper cover 419 formed of an aluminum alloy on the upper portion of the cooling circuit board 413 closes the upper opening of the housing 400. As described above, the housing 400 is firmly fixed by the fixing screw 420.

  Further, a control circuit unit substrate 421 on which a control circuit unit 172 for controlling the driver circuit 174 is mounted is disposed on the long side wall portion 400A of the housing 400, and a side cover 422 formed of an aluminum alloy is further provided on the control circuit unit substrate 421. The casing 400 is firmly fixed to the long side wall portion 400 </ b> A of the casing 400 by a fixing screw 423.

  The above is the schematic configuration of the power conversion device 200 according to an embodiment of the present invention. Next, details of characteristic components will be described.

  FIG. 6 shows a capacitor module 500 newly developed in accordance with the present embodiment. The capacitor module 500 includes a plurality (three) of positive side capacitor terminals 506, a plurality (three) of negative side capacitor terminals 504, and a positive electrode. A side power supply terminal 509 and a negative power supply terminal 508 are provided.

DC high voltage power from the battery 136 is supplied through the DC terminal 408 to the positive power supply terminal 509 and the negative electrode side power supply terminal 508, U plurality of positive electrode side capacitor terminals 506 and a plurality of negative electrode side of the capacitor module 500 capacitor The terminal 504 is connected to the power module 150.

  The capacitor module 500 has one side surface portion 500A, specifically, the side surface portion 500A in the direction in which the power module 150 is installed as shown in FIG. The negative-side capacitor terminal 504, the positive-side power terminal 509, and the negative-side power terminal 508 protrude.

  Thus, by arranging all the terminals on one side surface portion 500A, the interphase current is reduced between the phases (U phase, V phase, W phase), and as a result, the heat generated by the interphase current is reduced. It can be expected to suppress the phenomenon that heat is accumulated in the capacitor module 500. Further, the connection structure with the power module 150 can be simplified, and the distance of the connection wiring can be shortened.

  On the side surface portion 500A of the capacitor module 500, a positive electrode side capacitor terminal 506, a negative electrode side capacitor terminal 504, a positive electrode side power supply terminal 509, and a negative electrode side power supply terminal 508 are arranged in this order from the upper side. The conductor surface 506A of 506 is configured to be substantially flush with the upper surface portion 500B of the capacitor module 500. Therefore, this positive electrode side capacitor terminal 506 constitutes a part of the heat radiation path to the cooling board 413.

  In the present embodiment, the negative electrode side conductor plate, the positive electrode conductor plate, and the positive electrode side capacitor terminal 506, the negative electrode side capacitor terminal 504, the positive electrode side power supply terminal 509, and the negative electrode side power supply terminal 508 are integrally formed. It consists of a metal plate such as copper.

  The capacitor module 500 includes a capacitor element, a case 550 that stores the capacitor element, and a resin sealing material 551 that fills the storage space of the case 550. The exposed surface 552 is a surface of the resin sealing material 551 exposed from the case 550. The case 550 is disposed on the side of the power module 150 so that the exposed surface 552 and the power module 150 face each other. The positive-side capacitor terminal 506 and the negative-side capacitor terminal 504 are required to suppress an increase in bending portion from the viewpoint of improving productivity. Further, the positive-side capacitor terminal 506 and the negative-side capacitor terminal 504 are required to suppress an increase in the length of the capacitor terminal from the viewpoint of reducing inductance. Therefore, the positive electrode side capacitor terminal 506 and the negative electrode side capacitor terminal 504 protrude from the exposed surface 552 in parallel with the cooling surface of the cooling board 413 with the positive electrode side capacitor terminal 506 and are connected to the power module 150. Moreover, it can suppress that the contact area of a cooling board and a capacitor terminal becomes small by suppressing the increase in the bending part of a capacitor terminal.

  7A and 7B show the configuration of the cooling board 413. FIG. 7A is an overall perspective view of the cooling board, FIG. 7B is a front view seen from above, and FIG. As can be seen from these drawings, the cooling board 413 is formed with openings 413A for accommodating the upper portion of the capacitor module 500 and openings 413B and 413C through which connection terminals of electronic components such as the power module 150 pass. The cooling board 413 is entirely formed of a synthetic resin 413D, and two cooling plates 424 and 425 are embedded therein by insert molding.

  The reason why the cooling plate 424 and the cooling plate 425 are insert-molded by molding with the synthetic resin 413D is to insulate the cooling plate 424 and the cooling plate 425 from the electronic components and connection wiring arranged in the housing 400. .

  The cooling plate 424 is a cooling plate for releasing heat from the capacitor module 500, and the cooling plate 425 is a cooling plate for releasing heat from the AC connection bus bar 416. The cooling plate 425 also has a function of releasing heat generated in the power module 150 when the power module 150 is further heated.

  The cooling plate 424 and the cooling plate 425 are entirely covered with the synthetic resin 413A as described above, but only the bottom surface side is exposed so that heat can enter. Further, the cooling plate 424 and the cooling plate 425 are formed with a mounting portion 424A and a mounting portion 425A protruding from the synthetic resin portion 413D of the cooling board 413, and a hole through which a fixing screw for mounting is inserted is formed inside. Has been.

Accordingly, the heat entering from the exposed bottom surface of the cooling plate 424 and the cooling plate 425 embedded in the cooling board 413 is attached to the mounting portion 424A and the mounting portion 425 of the cooling plate 424 and the cooling plate 425.
It escapes from A to the housing 400.

  FIG. 8 is an external perspective view showing details of the cooling plate 424 and the cooling plate 425. The cooling plate 424 on the capacitor module 500 side has an opening at the center, and a plurality of positive electrode sides of the capacitor module 500 are surrounded by the opening. The heat receiving portion 424B receives heat from the capacitor terminal 506 side, the heat transfer portion 424C, and a mounting portion 424A that is a heat radiating portion.

  The cooling plate 425 on the AC connection bus bar 416 side is formed in a straight plate shape, and includes a heat receiving part 425B that receives heat from the AC connection bus bar 416 side, a heat transfer part 425C, and a mounting part 425A that is a heat dissipation part. .

  The cooling plate 424 and the cooling plate 425 are formed of a high heat transfer member having excellent heat transfer properties. In this embodiment, aluminum having a plate thickness of 2 mm is used. It is also possible to use a copper material if further heat extraction (high thermal conductivity) is required.

  In addition, the cooling plate 424 and the cooling plate 425 are separated and integrated with the synthetic resin 413D, but the cooling plate 424 and the cooling plate 425 are integrally punched with a punching machine, and this is insert-molded together with the synthetic resin 413D. You may make it do.

  The above metal materials have been proposed as materials that can be insert-molded into synthetic resin, but in addition to this, when using non-metallic materials with high heat transfer properties, the cooling board 413 is configured by affixing or fixing screws instead of insert molding. You may make it do. In this case, the cooling plate 424 and the cooling plate 425 may have the same shape as that shown in FIG.

  FIGS. 9A and 9B are external perspective views of the cooling board 413 as viewed from the back side, in which FIG. 9A shows a state where a heat dissipation sheet is attached, and FIG. 9B shows a state where the heat dissipation sheet is disassembled.

  In FIG. 9, the heat dissipation sheet 415 on the capacitor module 500 side is an insulating sheet portion 415 </ b> A formed in a shape slightly larger than the shape of the heat receiving portion 424 </ b> B of the cooling plate 424. It is composed of a composite sheet formed from a heat dissipation sheet portion 415B formed in a slightly larger shape, and an insulating sheet portion 415A is positioned on the heat receiving portion 424B side and a heat dissipation sheet portion 415B is positioned on the positive electrode side capacitor terminal 506 side It has become.

  As the material of the heat dissipation sheet 415, the insulating sheet portion 415A is made of PET (polyethylene terephthalate), and its thickness is made as thin as possible in order to improve heat dissipation, and the thickness is 0.1 mm. Yes. The heat radiation sheet portion 415B is made of a silicon-based resin material and has a thickness of 1.0 mm.

  Further, the heat dissipation sheet 417 on the AC connection bus bar 416 side is an insulating sheet portion 417A formed in a shape slightly larger than the shape of the heat receiving portion 425B of the cooling plate 425, and similarly, this is also slightly smaller than the shape of the heat receiving portion 425B of the cooling plate 425. It is composed of a composite sheet formed from a heat radiating sheet portion 417B formed in a large shape. The insulating sheet portion 415A is located on the heat receiving portion 425B side, and the heat radiating sheet portion 417B is located on the AC connection bus bar 416 side. ing.

  As a material of the heat radiation sheet 417, the insulating sheet portion 417A is made of PET (polyethylene terephthalate), and its thickness is made as thin as possible to improve heat radiation, and the thickness is 0.1 mm. Yes. The heat-dissipating sheet portion 417B is made of a silicon-based resin material and has a thickness of 1.0 mm.

  These heat radiation sheet 415 and heat radiation sheet 417 have flexibility as their characteristics, and due to this flexibility, the heat receiving portions 424B and 425B of the cooling plates 424 and 425, the positive side capacitor terminal 506, the AC connection bus bar 416, It is trying to adhere closely. As a result, the heat transfer efficiency is improved.

  The heat dissipation sheet 415 and the heat dissipation sheet 417 are not limited to the materials and thicknesses described, and other materials and specifications may be selected and adopted as appropriate. This is desirable from the standpoint of actual use.

  Note that the heat radiation sheet 415 and the heat radiation sheet 417 can be expected to be attached quickly to the cooling board 413 in advance before the cooling board 413 is incorporated into the housing 400.

  Next, a state where the newly developed capacitor module 500 and the cooling board 413 described above are incorporated in the housing 400 will be described.

  10 is a front view of the power conversion apparatus with the top cover 419 and the driver circuit board 418 removed, FIG. 11 is a front view of the state with the cooling board 413 removed, and FIG. 12 shows the power shown in FIG. It is sectional drawing which showed the BB cross section of the converter.

  In FIG. 10, a cooling board 413 is firmly fixed to the casing 400 of the power converter by a fixing screw 414 via an attachment portion 424A of the cooling plate 424 and an attachment portion 425A of the cooling plate 425.

  As shown in FIG. 11, the heat receiving portion 424 </ b> B of the cooling plate 424 is positioned so as to come into contact with the positive electrode side capacitor terminal 506 and the conductor surface 506 </ b> A of the capacitor module 500 via the heat radiation sheet 415.

  Similarly, the three AC connection bus bars 416 connecting the power module 150 and the AC terminal 407 are positioned so that the heat receiving portion 425B of the cooling plate 425 is in contact with the heat dissipation sheet 417. The AC connection bus bar 416 is thickened to increase the heat transfer area, and is in thermal contact with the heat receiving portion 425B via the heat dissipation sheet 417.

  Therefore, as shown in FIG. 12, the heat accumulated in the capacitor module 500 or the heat generated in the capacitor module 500 itself passes through the heat dissipation sheet 415 from the positive-side capacitor terminal 506 and its conductor surface 506A, and the heat receiving portion of the cooling plate 424. 424B, and further flows to the mounting portion 424A through the heat transfer portion 424C and is transmitted to the housing 400.

  The casing 400 is cooled by ambient air and a cooling medium flowing in and out of the pipe 406, so that the temperature is lower than that of the capacitor module 500. Due to this temperature gradient difference, the heat of the capacitor module 500 is transferred to the casing 400. It will flow efficiently.

  Further, the flow path forming body 470 forms a flow path through which the cooling refrigerant flows. The capacitor module 500 is disposed between the cooling board 413 and the flow path forming body 470. Thereby, the heat of the power module 150 transmitted through the positive capacitor terminal 506 and the negative capacitor terminal 504 is transmitted to the cooling board 413 and a flow path is formed on the opposite side of the cooling board 413 through the capacitor module 500. By providing the body 470, the cooling performance of the capacitor module 500 is further improved.

  In addition, the pipe 406 is disposed to face the capacitor module 500 with the flow path of the flow path forming body 470 interposed therebetween. The cooling refrigerant flowing from the inlet side pipe 406 is sufficiently cooled. Therefore, since the capacitor module 500 is cooled by the cooling refrigerant, the cooling performance is further improved.

  Here, the positive electrode side capacitor terminal 506 and the conductor surface 506A of the capacitor module 500 are in thermal contact with the cooling plate 424, but the polarity of the capacitor terminal is reversed and the heat of the capacitor module 500 from the cooling plate 424 is reversed. You may make it escape.

  Similarly, heat from the outside (for example, heat from the electric motor) flowing into the AC connection bus bar 416 from the AC terminal 407 is transmitted to the heat receiving unit 425B of the cooling plate 425 through the heat radiating sheet 417, and further to the heat transfer unit 425C. And flows to the mounting portion 425A and is transmitted to the housing 400. The casing 400 is cooled by the ambient air and the cooling medium flowing in and out of the pipe 406, so that the temperature is lower than that of the AC connection bus bar 416. Due to this temperature gradient difference, the heat of the AC connection bus bar 416 is 400 will flow efficiently.

  As described above, in the power conversion device, cooling of the power conversion device is extremely important in order to improve the power conversion performance. In particular, the DC smoothing capacitor module housed in the casing of the power conversion device is In order to ensure its performance, it is required to cool the capacitor module efficiently and to reduce the heat entering from the outside as much as possible.

  In order to meet such a demand, in the present invention, the heat of the capacitor module is released to the casing by the cooling plate provided on the cooling board, and the heat entering from the outside is released to the casing by the cooling plate provided on the cooling board. By doing so, it is possible to efficiently improve the thermal environment in the housing.

  Furthermore, according to the present embodiment, since the cooling board is only fixed to the casing, the apparatus is increased in size, the structure is complicated, the mold is greatly modified, and a new passage for the cooling medium is added. There is no need. Therefore, for example, when employed in an automobile as a power conversion device, an increase in the size of the housing can be avoided, the mountability can be improved, and the manufacturing cost can be reduced, and the economic effect is great. .

DESCRIPTION OF SYMBOLS 140 ... Inverter circuit part, 150 ... Power module, 172 ... Control circuit part, 174 ... Driver circuit, 200 ... Power converter, 400 ... Housing, 400A ... Long side wall part, 400B ... Short side wall part, 402 ... Storage part 403: Storage unit 404: Lower cover 405 Fixing screw 40 1 Heat dissipation sheet 407 AC terminal 408 DC terminal 409 AC side connection port 410 DC side connection port 413 Cooling board 414 ... Fixing screw, 415 ... Heat radiation sheet, 415A ... Insulation sheet part, 415B ... Heat radiation sheet part, 416 ... AC connection bus bar, 417 ... Heat radiation sheet, 417A ... Insulation sheet part, 417B ... Heat radiation sheet part, 418 ... Top cover , 420 ... Fixing screw, 421 ... Control circuit board, 422 ... Side cover, 424 ... Cooling plate, 424A ... Attaching part, 424B ... Heat receiving part, 424C ... Heat transfer part, 425 ... Cooling plate, 425A ... Mounting part, 425B ... Heat receiving part, 425C ... Heat transfer part, 500 ... Capacitor module, 500A ... Side face part, 506 ... Positive side capacitor Terminals 504... Negative side capacitor terminals 508. Negative side power terminals 509. Positive side power terminals

Claims (4)

A power module with a main electrode terminal;
A capacitor module;
A cooling board, and
The capacitor module includes a capacitor element, a capacitor terminal connected to the main electrode terminal, a case for forming an opening for storing the capacitor element and drawing out the capacitor terminal, and a resin filled in a storage space of the case And a sealing material ,
The resin sealing material has an exposed surface exposed from the opening of the case,
The capacitor module is arranged such that the exposed surface of the resin sealing material is along a direction in which the main electrode terminal of the power module protrudes,
The power module is disposed such that the main electrode terminal is positioned opposite the exposed surface of the resin sealing material,
The capacitor terminals, as mentioned above into contact with the cooling board, the power conversion apparatus according to claim <br/> that is pull out from the exposed surface of the resin encapsulant. The power conversion device according to claim 1,
A plurality of the power modules are provided,
A plurality of the capacitor terminals are provided corresponding to each of the plurality of power modules,
The cooling board is in contact with the plurality of capacitor terminals so as to straddle along the arrangement direction of the plurality of capacitor terminals.
The power converter characterized by the above-mentioned . The power conversion device according to claim 1 or 2,
The cooling board is in contact with the capacitor terminal via an insulating sheet having electrical insulation.
The power converter characterized by the above-mentioned . In the power converter device according to any one of claims 1 to 3,
The cooling board is thermally connected to a flow path forming body through which a coolant for cooling the power module flows.
The power converter characterized by the above-mentioned .

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