JP2015076990A - Power conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power conversion device that reduces an effect of heating of a power wiring pattern on a power supply circuit.SOLUTION: A power conversion device 1 includes: a power semiconductor element 328; a heat radiation member 26 for radiating heat from the power semiconductor element 328; a power board 24 mounted with the power semiconductor element 328 and formed with power wiring patterns 29U-29W; a control board 20 provided separately from the power board 24 and mounted with a drive control circuit 172 and a power supply circuit 30; and a wiring member 25 connected to both the boards 20, 24 like a bridge therebetween to transmit a control signal from the drive control circuit 172 to the power semiconductor element 328. The power semiconductor element 328 and the drive control circuit 172 are arranged in respective opposite positions with the wiring member 25 in between.

Description

  The present invention relates to a power converter for driving a motor.

  Power converters for driving motors such as air conditioner compressors and oil pumps mounted on vehicles have power semiconductor elements and power modules that supply three-phase power to the motors, and output drive control signals to the power modules And a power supply circuit for supplying power to the drive control circuit. These components are mounted on the same printed circuit board and connected by a wiring pattern (see, for example, Patent Document 1). The invention described in Patent Document 1 describes a configuration in which heat generated by a switching operation of a power semiconductor element is radiated by a heat radiating member.

JP 2007-214414 A

  By the way, in the power converter described above, heat is also generated when a large current flows through the power wiring pattern of the printed circuit board. The heat generated in the power wiring pattern is also transferred to the power supply circuit mounted on the board via the printed board. That is, the temperature rise of the electronic component provided in the power supply circuit due to heat generation of the power wiring pattern becomes a problem.

  A power conversion device according to a first aspect of the present invention includes a power semiconductor element that converts DC power to AC power, a heat dissipation member that dissipates heat from the power semiconductor element, and a power semiconductor element. A first substrate on which a power wiring pattern through which a current flows is formed, a drive control circuit that is provided separately from the first substrate and controls driving of the power semiconductor element, and a power source that supplies power to the drive control circuit And a wiring for transmitting a control signal from the drive control circuit to the power semiconductor element. The wiring is connected to each of the second board on which the circuit is mounted and the first board and the second board. The member, the power semiconductor element, and the drive control circuit are respectively disposed at positions facing each other with the wiring member interposed therebetween.

  According to the present invention, the influence of heat generation of the power wiring pattern on the power supply circuit can be reduced.

FIG. 1 is a perspective view showing an embodiment of a power converter according to the present invention. FIG. 2 is a circuit block diagram of the power conversion device 1. FIG. 3 is a diagram illustrating a state in which the control board 20 and the power board 24 are fixed to the heat dissipation member 26. It is a figure which shows the power converter device 1 of the state fixed to the heat radiating member 26. FIG. FIG. 4 is a diagram showing an example of the arrangement of the power supply circuit 30 on the control board 20 and the arrangement of the power wiring pattern on the power board 24. FIG. 5 is a diagram illustrating another example of the arrangement of the power supply circuit 30 on the control board 20 and the arrangement of the power wiring pattern on the power board 24. FIG. 6 is a diagram illustrating another example of a configuration in which the control board 20 and the power board 24 are connected by the wiring member 25. FIG. 7 is a diagram for explaining the influence of the magnetic field when the control board 20 and the power board 24 are arranged in a planar shape. FIG. 8 is a diagram for explaining the influence of the magnetic field when the control board 20 is disposed at an angle.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a power converter 1 according to the present invention. FIG. 2 is a circuit block diagram of the power conversion apparatus 1. In addition, the power converter device of this invention is applicable not only to the power converter device of motors, such as the oil pump mentioned above, but the compressor of an air-conditioner, but the power converter device which drives the motor of various uses.

  The power conversion apparatus 1 includes a power board 24 on which a power module 329 and a current sensor 180 are mounted, and a control board 20 on which a drive control circuit 172 and a power supply circuit 30 are mounted. The power board 24 and the control board 20 are electrically connected by a wiring member 25.

  First, the circuit configuration of the power conversion device 1 will be described with reference to FIG. The power module 329 includes six power semiconductor elements 328 constituting a three-phase bridge circuit. Each power semiconductor element 328 that is a semiconductor switching element is connected in parallel with a diode 327 for circulation. The collector electrode of the power semiconductor element 328 on the upper arm side is connected to the positive side P of the DC power supply, and the emitter electrode of the power semiconductor element 328 on the lower arm side is connected to the negative side N of the DC power supply.

  A U-phase power wiring pattern 29U is connected to the middle point (emitter-collector connection point) of the U-phase upper and lower arms. A V-phase power wiring pattern 29V is connected to the middle point (emitter-collector connection point) of the V-phase upper and lower arms. A W-phase power wiring pattern 29 </ b> W is connected to the middle point (emitter-collector connection point) of the W-phase upper and lower arms. Current sensors 180 are provided in the power wiring patterns 29U and 29V, respectively.

  A gate drive signal is input from the drive control circuit 172 to the gate electrode of each power semiconductor element 328. The drive control circuit 172 performs on / off control of each power semiconductor element 328 based on a PWM control signal input from a control device (not shown). The PWM control signal is input via a connector 21 mounted on the control board 20. The drive control circuit 172 operates with DC power supplied from the power supply circuit 30.

  As shown in FIG. 1, the power module 329 provided with the power semiconductor element 328 and the current sensor 180 are mounted on the back side of the power board 24. In FIG. 1, the power board 24 is indicated by a two-dot chain line so that the component arrangement can be easily understood. A plurality of terminals (AC output terminal, DC input terminal, control terminal, etc.) 190 protrude from the power module 329, and these terminals 190 are connected to the power board 24. The power wiring pattern for the U-phase, V-phase, and W-phase described above is formed on the power substrate 24, the U-phase terminal of the AC output terminal is connected to the U-phase power wiring pattern 29U, and the V-phase terminal is The V-phase power wiring pattern 29V is connected, and the W-phase terminal is connected to the W-phase power wiring pattern 29W. On the bottom surface side of the power module 329 (surface opposite to the surface on which the terminal 190 is provided), the heat dissipation member 26 is provided in close contact. In addition, in FIG. 1, the heat radiating member 26 is shown typically.

  A power supply circuit 30, a drive control circuit 172, and a connector 21 are mounted on the control board 20. In FIG. 1, detailed component configurations of the drive control circuit 172 and the power supply circuit 30 are omitted, and the drive control circuit 172 and the power supply circuit are disposed on both sides of a rectangular area (indicated by reference numerals 172 and 30) surrounded by a broken line. Electronic components constituting 30 are mounted. The connector 21 is fixed to the back side of the area indicated by the symbol A. The wiring member 25 that connects the power board 24 and the control board 20 transmits the gate drive signal generated by the drive control circuit 172 to the power module 329. The configuration of the wiring member 25 is not limited. For example, a printed board such as a flexible printed board or a rigid printed board may be used, or a wiring member such as a flat cable may be used. Also good.

  FIG. 3 is a diagram illustrating a state where the power conversion device 1 illustrated in FIG. 1 is fixed to the heat radiating member 26, and is a diagram of the power conversion device 1 viewed from the side. In addition, about the power module 329, a part was made into the torn surface. In the example shown in FIG. 3, the control board 20 and the power board 24 are connected by the wiring member 25 so that their board surfaces are substantially on the same plane. For example, the wiring member 25 is formed of a printed board, and the through hole of the printed board and the through hole of the control board 20 are connected by connection pins. The power board 24 is also connected to the wiring member 25 by the same method.

  When the control board 20 and the power board 24 are screw-fixed to the column 26a erected on the heat radiation member 26, the bottom surface of the power module 329 mounted on the back surface side of the power board 24 comes into contact with the upper surface of the heat radiation member. The power semiconductor element 328 provided in the power module 329 is fixed to the metal base plate 11 disposed on the bottom surface of the power module 329 via an insulating layer. Therefore, the rear surface of the metal base plate 11 is in close contact with the upper surface of the heat radiating member 26, and the heat generated in the power semiconductor element 328 is efficiently radiated to the heat radiating member 26 through the metal base plate 11. The heat radiating member 26 functioning as a heat sink radiates heat by water cooling or air cooling. The structure of the heat radiating member 26 is not limited to the structure shown in FIG. 3. For example, a structure in which an air-cooled heat sink on which heat radiating fins are formed is fixed to the bottom surface (heat radiating surface) of the power module 329.

  In FIG. 1, illustration of circuit components mounted on the control board 20 is omitted, but in the example illustrated in FIG. 3, a transformer 182 that is a component of the power supply circuit 30 and a power semiconductor that is a component of the drive control circuit 172. A driving IC 181 is shown. The transformer 182 and the connector 21 described above are mounted on the back side of the control board 20, and the power semiconductor drive IC 181 is mounted on the front side of the control board 20. The power semiconductor drive IC 181 is an IC that drives the power semiconductor element 328, and generates the gate drive signal described above.

  4 and 5 are diagrams illustrating the arrangement of the power supply circuit 30 on the control board 20 and the power wiring pattern on the power board 24. FIG. In the present embodiment, a board on which circuit components are mounted is configured by a first board (power board 24) and a second board (control board 20) separated from the first board. , 24 are electrically connected by a wiring member 25. The power board 24 is provided with a power module 329 having a power semiconductor element 328 having a large calorific value, and a power wiring pattern 29 (29U to 29W) that generates heat when a main current flows. On the other hand, a power supply circuit 30 and a drive control circuit 172 are mounted on the control board 20. The wiring member 25 transmits a control signal (gate drive signal) from the drive control circuit 172 mounted on the control board 20 to the power semiconductor element 328 provided on the power board 24.

  4 and 5, the wiring member 25 is connected to the connection region 20 a provided in the peripheral portion of the control board 20 and the connection region 24 a provided in the peripheral portion of the power board 24. In addition, the power module 329 is disposed adjacent to the connection region 24a, and the drive control circuit 172 is disposed adjacent to the connection region 20a. That is, the wiring members 25 are connected to each other so as to be bridged between the control board 20 and the power board 24, and transmit a control signal from the drive control circuit 172 to the power semiconductor element 328. The power semiconductor element 328 and the drive control circuit 172 are disposed at positions facing each other with the wiring member 25 interposed therebetween.

  Incidentally, the heat generated in the power module 329 can be radiated through the heat radiating member 26, but the heat radiating path of the heat generated in the power wiring pattern 29 is only the substrate. Therefore, when the power supply circuit 30, the drive control circuit 172, the power module 329, and the power wiring pattern 29 are arranged on a single board as in the prior art, the heat generated in the power wiring pattern 29 is transmitted via the board to the power supply circuit. 30 and the drive control circuit 172, and the temperature rises. The temperature rise is not preferable for circuit components, and the switching FET constituting the power supply circuit 30 has a lower allowable temperature (temperature rating) than other components. is there.

  On the other hand, in the present embodiment, the substrate is separated into the control substrate 20 and the power substrate 24, and the power semiconductor element 328 and the drive control circuit 172 are opposed to each other with the wiring member 25 interposed therebetween, as shown in FIGS. Therefore, the heat transfer path from the power wiring pattern 29 to the power supply circuit 30 can be made longer than before, and heat transfer from the power wiring pattern 29 to the power supply circuit 30 can be reduced.

  Further, the wiring distance between the power semiconductor element 328 provided in the power module 329 and the drive control circuit 172 that transmits a gate drive signal to the power semiconductor element 328 is preferably as short as possible from the viewpoint of power supply and signal waveform quality. In the example shown in FIGS. 4 and 5, the drive control circuit 172 and the power module 329 are arranged at positions facing each other with the wiring member 25 interposed therebetween, so that the drive control circuit 172 and the power module 329 are connected with the shortest distance. be able to.

  Further, in the configuration shown in FIG. 4, the boards 20 and 24 connected via the wiring member 25 are arranged so that one side 20 b of the control board 20 and one side 24 b of the power board 24 face each other, and the power module 329 The power wiring pattern 29 is arranged in parallel in the extending direction of the one side 24 b (the left-right direction in the figure), and the power supply circuit 30 and the drive control circuit 172 are arranged on one side of the control board 20 so that the power supply circuit 30 faces the power wiring pattern 29. 20b is arranged in parallel in the extending direction (the left-right direction in the figure).

  With such an arrangement, heat transfer from the power wiring pattern 29 to the power supply circuit 30 can be reduced as described above, the drive control circuit 172 and the power module 329 are connected in the shortest distance, and the control board The arrangement space of the entire board composed of 20 and the power board 24 can be kept small. For example, when the power supply circuit 30 and the power wiring pattern 29 are arranged as shown in FIG. 5, the arrangement space in the left-right direction in the figure is larger than that in the case of FIG.

  FIG. 6 is a diagram illustrating another example of a configuration in which the control board 20 and the power board 24 are connected by the wiring member 25. In FIG. 6, the substrate surface of the control board 20 extends in a direction substantially perpendicular to the board surface of the power board 24 by forming the wiring member 25 into a shape bent into an L shape. As shown in FIG. 4, the control board 20 indicated by a two-dot chain line shows a case where the boards 20 and 24 are arranged on substantially the same plane, and the arrangement space in the horizontal direction in the drawing is d2. On the other hand, when it arrange | positions at L shape like FIG. 6, the arrangement space of the illustration left-right direction becomes small like d1. Thus, by connecting the substrates 20 and 24 with the wiring member 25 so that the substrate surface of the control substrate 20 is inclined with respect to the substrate surface of the power substrate 24, the arrangement space of the substrates 20 and 24 can be reduced. it can. In the example shown in FIG. 6, the angle formed between the control board 20 and the power board 24 is approximately 90 degrees, but is not limited to 90 degrees, and may be larger than 90 degrees, for example.

  In addition, as shown in FIG. 6, when the control board 20 is inclined and bent so as to be bent in the direction of the power board 24, a tall component (high height) among a plurality of circuit components mounted on the control board 20 is used. Back component), for example, the transformer 182 included in the connector 21 or the power supply circuit 30 is preferably mounted on the surface opposite to the power substrate 24 side, that is, on the back surface side (the left surface in the drawing) of the control substrate 20. . As shown in FIG. 6, when the power module 329 is mounted on the power board 24, solder connection is performed from the surface (upper surface in the drawing) side of the power board 24. In that case, if the high-profile parts are mounted on the surface side of the control board 20, when the soldering operation is performed with a soldering device (soldering iron or robotic solder), the high-profile parts interfere with each other. It becomes difficult. Therefore, as described above, it is preferable to mount the high-profile component on the back surface side (the surface opposite to the power substrate 24 side) of the control board, so that the soldering work can be performed efficiently.

  7 and 8 are diagrams for explaining the influence of the magnetic field generated by the power supply circuit 30 on the current sensor 180. FIG. FIG. 7 shows a case where the control board 20 and the power board 24 are arranged in a plane as shown in FIGS. The current sensor 180 is a current sensor of a type that measures a current value by detecting a component in a direction (normal direction) perpendicular to the power substrate 24 in a magnetic field formed by a current flowing through the power wiring pattern 29. That is, the arrow 31 indicates the magnetic field detection direction of the current sensor 180.

  A broken line indicated by reference numeral 34 schematically shows a magnetic field that affects the current sensor 180 in the magnetic field generated by the power supply circuit 30. The power supply circuit 30 is a switching power supply, and a large current flows or stops with switching, and a magnetic field is generated accordingly. Among these magnetic fields, the magnetic field 34 shown in FIG. 7 coincides with the magnetic field detection direction of the current sensor 180. Such a magnetic field is formed by a current component that flows in a straight direction on the paper surface. Since the direction of the magnetic field 34 is perpendicular to the power substrate 24 in the vicinity of the current sensor 180, the current value detection value of the current sensor 180 is affected.

  On the other hand, as shown in FIG. 8, when the control board 20 is inclined with respect to the power board 24, the direction of the magnetic field 34 in the vicinity of the current sensor 180 is inclined with respect to the vertical direction of the power board 24. As a result, the influence on the current value detection of the current sensor 180 can be reduced. FIG. 8 shows the case where the inclination of the control board 20 with respect to the power board 24 is approximately 90 degrees, but the reduction effect can be obtained even with an inclination other than 90 degrees.

  Note that the present invention is not limited to the above embodiment as long as the characteristics of the present invention are not impaired. Moreover, you may use each embodiment mentioned above individually or in combination. This is because the effects of the respective embodiments can be achieved independently or synergistically.

  1: power converter, 20: control board, 21: connector, 24: power board, 29, 29U, 29V, 29W: power wiring pattern, 30: power supply circuit, 172: drive control circuit, 180: current sensor, 328: Power semiconductor element, 329: Power module

Claims (5)

A power semiconductor element that converts DC power to AC power;
A heat dissipating member that dissipates heat of the power semiconductor element;
A first substrate on which the power semiconductor element is mounted and a power wiring pattern through which a main current from the power semiconductor element flows is formed;
A second substrate provided separately from the first substrate and mounted with a drive control circuit for driving and controlling the power semiconductor element and a power supply circuit for supplying power to the drive control circuit;
A wiring member connected to each of the first substrate and the second substrate so as to be bridged between the first substrate and the second substrate, and transmitting a control signal from the drive control circuit to the power semiconductor element;
The power conversion device, wherein the power semiconductor element and the drive control circuit are respectively disposed at positions facing each other with the wiring member interposed therebetween. The power conversion device according to claim 1,
The first and second substrates connected via the wiring member are arranged so that one side of the first substrate and one side of the second substrate face each other.
The power semiconductor element and the power wiring pattern provided on the first substrate are juxtaposed in the extending direction of one side of the first substrate,
The power supply circuit and the drive control circuit provided on the second substrate are juxtaposed in the extending direction of one side of the second substrate so that the power supply circuit faces the power wiring pattern. Power conversion device. In the power converter device according to claim 1 or 2,
The power conversion device, wherein the first and second substrates are connected by the wiring member such that the substrate surface of the second substrate is inclined with respect to the substrate surface of the first substrate. The power conversion device according to claim 3,
Power conversion comprising a current sensor mounted on the first substrate and detecting a component of a magnetic field formed by a current flowing through the power wiring pattern perpendicular to the substrate surface of the first substrate to measure a current apparatus. The power conversion device according to claim 3,
The high-profile components included in the plurality of circuit components mounted on the second substrate are mounted on the substrate surface opposite to the first substrate side of the second substrate disposed at an angle. The power converter.

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