JP2010084669A - Inverter-integrated electric compressor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverter-integrated electric compressor capable of reducing noise from bypassing a noise filter caused by parasitic capacity coupling and sufficiently exhibiting a noise removal effect of the noise filter connected to a low voltage cable. <P>SOLUTION: This inverter-integrated electric compressor includes: an inverter device 20 having a power substrate 210 for converting DC power supplied from a high voltage power source into AC power and applying the AC power to an electric motor, and a control board 211 for controlling the application of the AC power to the electric motor; and a low voltage noise filter substrate 30 disposed between a low voltage cable 31 for supplying power fed from a low voltage power source to the control board 211 and the control board 211. By providing the low voltage noise filter substrate 30 separate from the control board 211, the parasitic capacity coupling is reduced, and the noise removal effect is sufficiently exhibited. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric motor that drives a compression mechanism, and an inverter-integrated electric compressor in which an inverter control device that controls the electric motor is integrated with the compression mechanism.

  An on-vehicle air conditioner in an electric vehicle, a fuel cell vehicle, or the like that is not equipped with an engine has a compressor that incorporates an electric motor as a power source for compressing and circulating the refrigerant. This compressor includes an inverter device that converts DC power supplied from a battery, which is a vehicle-mounted power source, into three-phase AC power and supplies it to an electric motor. From the request of space saving, an integrated electric compressor in which an inverter device is incorporated in a single housing together with a compression mechanism and an electric motor is known (for example, Patent Document 1 and Patent Document 2).

  The inverter device includes a power board on which a plurality of semiconductor switching elements (for example, an IGBT (Insulated Gate Bipolar Transistor) and an FET (Field Effect Transistor)) for converting DC power into three-layer AC power, And a control board on which a control communication circuit having elements operating with voltage is mounted.

JP 2004-190525 A JP 2004-190547 A

The inverter-integrated electric compressor prevents communication of noise from the outside into the inverter device and prevents the noise generated by the inverter device from leaking to the outside. Hereinafter, a noise filter is provided between the low voltage cable) and the control board. This noise filter includes a common mode choke coil, a normal mode choke coil, and a smoothing capacitor. Until now, a noise filter composed of these components has been mounted on a control board.
However, when the noise filter is mounted on the control board, the part where the low voltage cable is connected to the control board and the main circuit part such as the CPU of the control board are too close to each other. The effect cannot be fully enjoyed. Here, “close” means not only spatial proximity but also electrical proximity due to parasitic capacitive coupling. In other words, since noise can pass through the parasitic capacitance coupling component, external noise bypasses the noise filter and flows into the inverter device, or noise from the inverter device bypasses the noise filter and leaks outside. End up.

In order to avoid the noise bypassing the noise filter, it is necessary to eliminate the conductive pattern directly under the noise filter, but this detracts from the freedom of circuit design. Further, when the control board is composed of a plurality of layers, there is a restriction that the interior conductive pattern cannot be provided immediately below the noise filter.
Further, in order to mount the noise filter, a space is required on the control board, and the area of the control board increases accordingly. In particular, in order to reduce parasitic capacitance coupling, it is necessary to provide a distance between the noise filter and the conductive pattern, and space is required in addition to mounting the noise filter.
The present invention has been made on the basis of such a technical problem, and is an inverter-integrated electric motor capable of reducing noise bypass due to parasitic capacitance coupling and sufficiently exhibiting the noise removal effect of a noise filter connected to a low-voltage cable. An object is to provide a compressor.

  The present inventor has conceived of mounting the noise filter that has been mounted on the control board until now on a board separate from the control board. Since the separate substrate can have fewer conductive patterns that cause parasitic capacitance coupling than the control substrate, noise bypass due to parasitic capacitance coupling can be minimized. On the other hand, providing the filter board separately from the control board requires more space, but even with the same housing as before, there is room to provide the filter board above or on the side of the control board. There is. Therefore, even if the noise filter is mounted on a board separate from the control board, it is not necessary to enlarge the housing.

  The inverter-integrated electric compressor of the present invention based on the above examination results is obtained by using a compression mechanism that sucks in, compresses and discharges refrigerant, an electric motor that drives the compression mechanism, and direct-current power supplied from a high-voltage power supply. A power board that converts the power into the electric motor and a control board that controls the application of AC power to the electric motor, and an inverter control device that controls the driving of the electric motor, and power that is supplied from the low-voltage power supply A low voltage noise filter board disposed between the control board and a low voltage cable that supplies the control board to the control board, and a housing that houses the compression mechanism, the electric motor, the inverter control device, and the low voltage noise filter board. It is characterized by providing.

  In the inverter-integrated electric compressor according to the present invention, the housing includes an inverter accommodating portion that accommodates the modularized inverter control device, and the low-voltage noise filter substrate is controlled above the control substrate in a gap in the inverter accommodating portion. It can be arranged parallel to the substrate or beside the control substrate and perpendicular to the control substrate.

  In the inverter-integrated electric compressor of the present invention, the low voltage noise filter board and the control board are connected by wiring, and the connection portion between the wiring and the control board is separated from the arrangement position of the low voltage noise filter board. Even so, the wiring can be traversed on the control board. Since the noise is removed by the low voltage noise filter substrate, the noise does not enter the inverter device even if the wiring is routed on the control substrate.

  According to the present invention, there is provided an inverter-integrated electric compressor capable of reducing noise bypass due to parasitic capacitance coupling and sufficiently exhibiting a noise removal effect of a noise filter connected to a low voltage cable.

Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings.
FIG. 1 is a plan view showing a state in which the lid of the inverter accommodating portion 9 of the inverter-integrated electric compressor 1 according to the present embodiment is removed. FIG. 2 is a plan view in a state where the inverter module 21 is further removed. These are the longitudinal cross-sectional views of the state of FIG.
The inverter-integrated electric compressor 1 has a substantially cylindrical housing 2 that forms an outer shell thereof. The housing 2 is configured by integrally fastening and fixing a motor housing 4 in which the electric motor 3 is accommodated and a compressor housing 5 in which a compression mechanism (not shown) is accommodated with bolts 6. The housings 4 and 5 are made by die casting an aluminum alloy. Here, mainly the motor housing 4 side of the inverter-integrated electric compressor 1 is shown.

  An electric motor 3 and a compression mechanism (not shown) built in the housing 2 are connected via a motor shaft 7 and are configured such that the compression mechanism is driven by the rotation of the electric motor 3. A suction port 8 for sucking low-pressure refrigerant gas is provided on the outer peripheral side of the rear end side of the housing 2 (motor housing 4). The refrigerant gas sucked into the housing 2 from the suction port 8 flows around the electric motor 3 in the axial direction of the motor shaft 7 and is then sucked into the compression mechanism and compressed. The high-temperature and high-pressure refrigerant gas compressed by the compression mechanism is discharged to the discharge chamber in the housing 2 (compressor housing 5) and then provided on the front end side of the housing 2 (compressor housing 5). It is configured to be sent to the outside from a substantially discharge port.

  For this reason, on the side of the motor housing 4 in which the electric motor 3 of the housing 2 is built, low-pressure gas refrigerant is sucked from the suction port 8 provided on the rear end side, and this is circulated to the compressor housing 5. This is the low pressure side part. The compressor housing 5 connected to the motor housing 4 has a discharge chamber for discharging compressed high-pressure refrigerant gas on the side opposite to the motor housing 4 with a built-in compression mechanism as a boundary. It is considered as a high-pressure side part.

  The housing 2 is provided with attachment feet (not shown) at a total of three locations, for example, a lower portion on the rear end side, a lower portion on the front end side, and an upper portion. The inverter-integrated electric compressor 1 is mounted on a vehicle by fixing bolts and arms to a cantilever bracket provided on a side wall of a driving motor for the vehicle via the mounting legs. The inverter-integrated electric compressor 1 is generally cantilevered at three points in the vertical direction with one side faced along a cantilevered bracket with the motor axial direction directed in the front-rear direction or the left-right direction of the vehicle. It is normal.

  Furthermore, an inverter housing portion 9 having a substantially rectangular planar shape is integrally formed on the upper surface of the outer periphery of the housing 2 (motor housing 4). The inverter accommodating portion 9 has a box-like structure surrounded by a peripheral wall 91 having a predetermined height with an open upper surface, and the inverter module 21 constituting the inverter device 20 is accommodated and installed. The upper surface of the inverter accommodating part 9 is closed with a lid (not shown).

  The inverter accommodating portion 9 has a substantially flat bottom surface corresponding to the outer peripheral surface of the housing 2, and a contact surface 10 with which the back surface of the power board 210 constituting the inverter module 21 is contacted, an inverter An installation boss 11 in which the module 21 is installed, a mounting groove 13 in which a glass hermetic terminal 12 for feeding the three-phase AC power converted by the inverter device 20 to the electric motor 3 is installed, and a high-voltage noise filter (not shown). An installation surface 15 is provided on which a relay bus bar 14 that supplies high-voltage DC power to the inverter module 21 is installed.

  In the inverter accommodating portion 9, an inverter module 21 that constitutes a circuit portion of the inverter device 20 is installed on the installation boss 11 via screws 22. In the inverter module 21, a plurality of semiconductor switching elements such as IGBTs and a power board 210 on which a drive circuit thereof is mounted, and a control board 211 on which a control communication circuit driven by a low voltage such as a CPU is mounted are made of resin. The case is configured and integrated into a module. The bottom surface of the power board 210 is brought into contact with the contact surface 10 in the inverter housing portion 9, and the control board 211 functions as a lid for closing the box-shaped upper opening of the inverter module 21, and the inside of the housing 2 (motor housing 4). It is installed so as to be cooled via the circulating low-pressure refrigerant gas.

  In the inverter module 21, the three-phase AC power converted from the PN terminals 23 </ b> A and 23 </ b> B and the inverter device 20 through the relay bus bar 14 is supplied to the electric motor so as to protrude from the outer periphery of the inverter module 21. 3 is provided with U-V-W terminals 24A, 24B and 24C which feed power via the glass sealed terminal 12.

  In the vicinity of one corner in the inverter accommodating portion 9, the low voltage noise filter substrate 30 is disposed on the control substrate 211 via the spacer 32. The low voltage noise filter substrate 30 is disposed so as to cover the communication circuit unit 212 of the control substrate 211. The low voltage cable 31 for communication and low voltage power supply is electrically connected to a conductive pattern (not shown) connected to the communication circuit unit 212 of the control board 211 via the low voltage noise filter board 30. The low voltage noise filter substrate 30 is provided in order to prevent external noise from flowing into the inverter device 20 via the low voltage cable 31 and to prevent leakage of noise generated by the inverter device 20 to the outside. The low voltage noise filter substrate 30 is composed of components known as noise filters such as a common mode choke coil, a normal mode choke coil, and a smoothing capacitor.

The above inverter-integrated electric compressor 1 has the following effects.
The low voltage power from the power supply unit mounted on the vehicle and the command signal from the main controller are supplied to the communication circuit unit 212 of the control board 211 via the low voltage cable 31 and the low voltage noise filter board 30. Therefore, noise and current ripple are removed by the low voltage noise filter substrate 30 and do not reach the control substrate 211. Conversely, the noise generated by the inverter device 20 is prevented from leaking to the outside by the low voltage noise filter substrate 30.

  In the inverter-integrated electric compressor 1, the low-voltage noise filter that has been mounted on the control board 211 so far is provided on the low-voltage noise filter board 30 that is separate from the control board 211. Accordingly, since the parasitic capacitance coupling can be reduced as compared with the case where the low voltage filter circuit is mounted on the control board 211, the noise filter can sufficiently exhibit the noise removal effect. Conventionally, in order to avoid parasitic capacitance coupling, there is a restriction on the position where the low voltage noise filter is mounted. However, if the separate low voltage noise filter substrate 30 is used, the restriction is not imposed. The degree of freedom in circuit design of the substrate 211 increases, and the space available for the control substrate 211 becomes wider.

  In the inverter-integrated electric compressor 1, the low voltage noise filter substrate 30 is disposed in the vicinity of the corner in the inverter accommodating portion 9, so that the low voltage noise filter substrate 30 and the peripheral wall 91 are close to each other. Then, since there are few portions that contain noise in the inverter accommodating portion 9, noise flowing into the inverter device 20 can be minimized. Further, the inverter-integrated electric compressor 1 is provided with the low-voltage noise filter substrate 30 immediately above the control substrate 211. Then, since the distance from the inverter device 20 to the low voltage noise filter substrate 30 is short, the leakage of noise generated from the inverter device 20 to the outside can be minimized.

In addition, since the inverter-integrated electric compressor 1 is provided as the low-voltage noise filter substrate 30 that is separate from the control substrate 211, the area of the control substrate 211 can be reduced by the amount of the noise filter.
Further, in the conventional inverter-integrated electric compressor in which the low-voltage filter circuit is mounted on the control board 211, there is a gap above the inverter device 20 in the inverter accommodating portion 9. In the inverter-integrated electric compressor 1, the low-voltage noise filter substrate 30 is disposed in the gap, so that it is not necessary to change the shape and size of the housing 2. That is, the inverter-integrated electric compressor 1 can effectively utilize the voids that have been wasted in the housing 2 and can improve the noise removal effect.

By the way, the communication circuit unit 212 is far from the high-voltage PN terminals 23A and 23B and the U-V-W terminals 24A, 24B, and 24C in order to prevent noise from flowing into the communication wiring (or the position shown in FIG. 1 (or It is desirable to arrange it in the vicinity thereof. Conventionally, a low voltage noise filter had to be mounted in the vicinity of the communication circuit unit 212. Therefore, in order to minimize the portion where noise before passing through the noise filter is not removed, the position where the low voltage cable is taken out is shown in FIG. 4 is limited to the immediate vicinity of the communication circuit unit 212 indicated by a one-dot broken line.
However, since the inverter-integrated electric compressor 1 has noise removed after passing through the low-voltage noise filter substrate 30, the wiring 33 that connects the low-voltage noise filter substrate 30 and the control substrate 211 is shown in FIG. As shown in FIG. 2, the control board 211 in the inverter housing 9 can be routed relatively freely. Therefore, according to the present invention, as shown by a solid line in FIG. 4, the degree of freedom of providing the low-voltage noise filter substrate 30 or providing the take-out position of the low-voltage cable 31 at a location away from the communication circuit unit 212 is increased. .

In the inverter-integrated electric compressor 1 described above, the low-voltage noise filter substrate 30 is disposed in parallel with the control substrate 211. However, as described below, the present invention is not limited thereto.
As shown in FIGS. 5 and 6, there is a gap between the peripheral wall 91 of the inverter housing portion 9 and the inverter module 21. Therefore, the low-voltage noise filter substrate 30 can be disposed perpendicular to the control substrate 211 in this gap. Of course, it can be arranged at any angle, not just vertical. In this case, the wiring 33 is preferably flexible.
Thus, by making the noise filter a separate body from the control board 211 as the low-voltage noise filter board 30, it is possible to effectively utilize the vacant space of the inverter accommodating portion 9 and to sufficiently remove the noise removal effect of the noise filter. Can demonstrate.

It is a top view which shows the state which removed the cover of the inverter accommodating part of the inverter integrated electric compressor in this Embodiment. It is a top view of the state which removed the inverter module of the inverter integrated electric compressor in this Embodiment. It is a longitudinal cross-sectional view of the state of FIG. It is a top view which shows the state which removed the lid | cover of the inverter accommodating part of the inverter integrated electric compressor in other this Embodiment. It is a top view which shows the state which removed the cover of the inverter accommodating part of the inverter integrated electric compressor in other this Embodiment. It is a longitudinal cross-sectional view of the state of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Inverter integrated electric compressor 2 ... Housing 3 ... Electric motor 4 ... Motor housing 5 ... Compressor housing 9 ... Inverter accommodating part 20 ... Inverter apparatus, 21 ... Inverter module,
210 ... Power board, 211 ... Control board, 212 ... Communication circuit section 30 ... Low voltage noise filter board, 31 ... Low voltage cable

Claims (2)

A compression mechanism that sucks, compresses and discharges the refrigerant;
An electric motor for driving the compression mechanism;
A power board that converts DC power fed from a high-voltage power source into AC power and applies the AC power to the electric motor; and a control board that controls application of the AC power to the electric motor, and drives the electric motor. An inverter control device to control;
A low voltage noise filter substrate disposed between the control board and a low voltage cable that supplies power supplied from a low voltage power supply to the control board;
A housing that houses the compression mechanism, the electric motor, the inverter control device, and the low-voltage noise filter substrate;
With
The inverter-integrated electric compressor, wherein the low-voltage noise filter substrate is separate from the control substrate. The housing is
Comprising an inverter housing portion for housing the inverter control device modularized;
The low voltage noise filter substrate is:
2. The gap in the inverter accommodating portion is disposed above the control board in parallel to the control board or on the side of the control board perpendicular to the control board. The inverter-integrated electric compressor according to 1.

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