JP2002165466A - Electric compressor driver for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric compressor driver of a vehicle, which has higher degrees of freedom for its mounting to a vehicle. SOLUTION: A filter capacitor for filtering a current to an inverter circuit from a battery is connected to the inverter circuit via a shield wire or a parallel wire. Since the shield wire or parallel wire has a smaller inductance than that of an ordinary lead wire, the inductance does not increase, even if the wire length is increased. Moreover, the filter capacitor can be connected separated from the inverter circuit. A large filter capacitor may be disposed in separation to the convenient place. Thereby, the electric compressor driver can be designed as a whole into a compact shape, and the degrees of freedom of loading to the vehicle can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in the degree of freedom in mounting an electric compressor driving device for a vehicle on a vehicle.

[0002]

2. Description of the Related Art A conventional electric compressor driving device for a vehicle will be described below with reference to the drawings. FIG.
(A) is a perspective view showing an external configuration of an example of a conventional electric compressor driving device for a vehicle, and (b) is a perspective view showing an internal configuration thereof.

[0003] As shown in FIG.
Is connected to a battery of about 300 V which is a DC power supply.

An inverter circuit for converting a current from the battery into an alternating current is provided therein. This inverter circuit generates heat due to DC / AC conversion loss. This heat is radiated to the cooling water flowing through the water cooling pipe 2. This heat radiation method is not limited to water cooling, and there is an example using an air cooling method. With such a structure, there is an advantage that the electric compressor driving device can be relatively freely arranged on the vehicle.

FIG. 7 shows the inside of the electric compressor driving device.
As shown in (b), a circuit board 3 on which electric components are mounted and a smoothing capacitor 4 for smoothing a current from a battery to an inverter circuit are arranged. Note that the outer contour line 5 indicates the outer contour.

FIG. 8 is a perspective view showing the circuit board 3 and related components. In FIG. 8, the circuit board 3 has an inverter circuit section 6 which is a block of an inverter circuit, and a reverse power supply for preventing a current from flowing when the power supply lead wire 1 is connected to the battery in the opposite direction. The connection protection diode 7 is connected. Such consideration is taken because the power supply lead 1 passes through several connectors to the battery. The reverse connection protection diode 7 is large because it flows a current of about 10 A, causes a loss of about 20 W, and requires cooling. Therefore, both the inverter circuit section 6 and the reverse connection protection diode 7 are attached to the cooling structure related to the water cooling pipe 2.

FIG. 9 is a circuit block diagram showing an outline of the configuration of the above-described conventional driving motor drive device and electric compressor drive device. In FIG. 9, a battery 8 is connected to a driving motor drive device 10 and an electric compressor drive device 11 through a power supply device 9. The traveling motor drive device 10 has an inverter circuit 10a, and is provided with an electrolytic capacitor 10b for smoothing a current from the battery 8 to the inverter circuit 10a. A traveling motor 12, which is a load, is connected to the inverter circuit 10a. The electric compressor driving device 11 also has an inverter circuit 13, and a smoothing capacitor 4 composed of an electrolytic capacitor is provided to smooth the current from the battery 8 to the inverter circuit 13.

[0008] Also, the inverter circuit 1 from the battery 8
On the way to 3, the reverse connection protection diode 7 is connected. An electric compressor 14 as a load is connected to the inverter circuit 13. The energizing device 9 charges the electrolytic capacitor 10b and the smoothing capacitor 4 to the voltage of the battery 8 by the charging resistor 9a, and thereafter, from the battery 8 to the inverter circuit 10a by the main relay 9b.
And a current flows to the inverter circuit 13.

FIG. 10 is a circuit block diagram showing a configuration of a conventional electric compressor driving device 11. As shown in FIG. The connection to the driving motor drive device 10 and the like is omitted. In FIG. 10, a 12V power supply 15 is mainly used as a power supply for an inverter control microcomputer 16 and a communication circuit 17. The 12 V power supply 15 is electrically insulated from the battery 8. It is also used as a power source for many electric devices such as the air-conditioning control unit 18, audio and navigation system. Current is supplied from the battery 8 to the 12V power supply 15 by the DC converter.

A voltage input from the battery 8 to the electric compressor driving device 11 is divided by an upper voltage dividing resistor 19 and a lower voltage dividing resistor 20, electrically insulated by a voltage detecting section 21, and controlled by an inverter controlling microcomputer. 16 is input. The current flowing through the inverter circuit 13 is detected by a current sensor 22, electrically insulated by a current detection unit 23, and input to the microcomputer 16 for inverter control. The air-conditioning control unit 18 calculates the required capacity (such as the number of revolutions) of the electric compressor 14 as an air conditioner, and inputs the result to the inverter control microcomputer 16 via the communication circuit 17.

The microcomputer 16 for inverter control sends a signal to the gate drive circuit 24 based on at least these inputs to operate the switching elements of the inverter circuit 13 to drive the electric compressor 14. The gate drive circuit 24 also has a function of electrically insulating the inverter circuit 13 and the microcomputer 16 for inverter control. In addition, the inverter control microcomputer 16 also receives continuous temperature data from the thermistor temperature sensor of the electric compressor 14 and the like. The switching power supply 25 produces a power supply for the gate drive circuit 24 and the like.

FIG. 11A is a waveform diagram showing an example of a current flowing into the inverter circuit 13, and FIG.
5 is a waveform diagram showing a current flowing into the electric compressor driving device 11. FIG. Although the waveform of the current flowing into the inverter circuit 13 is rectangular, the electric compressor driving device 1
The current flowing into 1 has a pulsation but includes a constant current because the current flowing into the inverter circuit 13 is smoothed by the smoothing capacitor 4.

[0013]

In such a configuration of the conventional electric compressor driving device, the shape is mainly increased by the metal case and the smoothing capacitor 4, so that it is different from a small electric vehicle and a hybrid electric vehicle. It becomes difficult to mount the device on a vehicle with a small arrangement space. Since the hybrid electric vehicle also has an engine, the arrangement space is further reduced. Therefore, it is not provided with a heat radiating structure such as a metal case and a water cooling pipe 2 and is installed in a case provided for the traveling motor drive device 10 to radiate heat to a radiator for the traveling motor drive device 10. Thus, miniaturization can be considered. Further, the circuit board 3 can be reduced in size and weight by reducing the size of electric and electronic components.

However, the smoothing capacitor 4 has a problem that it is difficult to reduce the size and weight of the smoothing capacitor 4 because the capacitance and the withstand voltage depend on the structure and the size. ing. Therefore, the smoothing capacitor 4 may be arranged at an easy-to-place place away from the circuit board 3 and electrically connected to the circuit board 3. However, if the distance is long, the generation of surge voltage due to the inductance of the electric connection line may occur. There is a concern that DC / AC conversion loss may increase due to waveform distortion of the current flowing into the inverter circuit 13.

FIG. 12A is a waveform diagram showing an example of a current flowing into the inverter circuit. FIG. 12B is a waveform diagram showing a voltage applied to the inverter circuit when the inductance value of the electric connection line is small. (C) is a waveform diagram showing a voltage when the inductance value is large. FIG. 12 (c)
Is generated when the current flowing into the inverter circuit shown in FIG. 12A becomes ΔFF,
This may cause damage to the inverter circuit 13 and the like. If there is no inductance in the electric connection line, no surge voltage is generated as shown in FIG. FIG.
When the current flowing into the inverter circuit shown in (a) is turned on, the current is distorted due to the inductance of the electric connection line, which causes an increase in DC / AC conversion loss.

An object of the present invention is to solve the above-mentioned problems and to provide an electric compressor driving device having a high degree of freedom in mounting on a vehicle.

[0017]

According to the present invention, a smoothing capacitor for smoothing a current from a DC power supply to an inverter circuit is connected to the inverter circuit via a shielded line or a parallel line. This is an electric compressor drive device for an automobile to be connected.

According to the present invention, the inductance value of the electrical connection line of the smoothing capacitor is small and stable. Therefore, performance and reliability can be maintained even if the electric connection line of the smoothing capacitor is lengthened, and the arrangement of the smoothing capacitor is free, so that an electric compressor driving device with a high degree of freedom in mounting on a vehicle can be realized. it can.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to an electric compressor drive for an automobile having an inverter circuit for converting a current from a DC power supply into an AC current, and a smoothing capacitor for smoothing the current from the DC power supply to the inverter circuit. In the apparatus, an electric compressor driving apparatus for a vehicle is configured such that the smoothing capacitor is electrically connected to the inverter circuit via a shielded line or a parallel line.

In the present invention, the electric connection by the shielded line or the parallel line reduces the inductance value of the smoothing capacitor as the electric connection line. Also, since the distance between different pole wires is fixed compared to the case of two lead wires,
The inductance value stabilizes.

Therefore, even if the electrical connection line of the smoothing capacitor is lengthened, it is possible to prevent surge voltage, DC / AC conversion loss and the like from increasing, and the layout of the smoothing capacitor is free, so that the degree of freedom of mounting the electric compressor driving device on the vehicle is improved. Can be improved. In addition, since the inductance value is stable, it is easy to calculate the inductance value in proportion to the wire length, and it is possible to optimize the design within the allowable value of surge voltage and DC / AC conversion loss (within the allowable value of inductance value). A highly reliable design is possible.

Hereinafter, embodiments of the present invention will be described.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) Hereinafter, Embodiment 1 of an electric compressor driving device for a vehicle according to the present invention will be described with reference to the drawings.

FIG. 1 is a circuit block diagram showing the configuration of this embodiment. The same components as those in the conventional example are given the same numbers.

As shown in FIG. 1, the smoothing capacitor 4 for smoothing is connected via one shield wire 26 as compared with the conventional example shown in FIG. Conventionally, they are connected by two lead wires. The current flowing through the shield wire 26 is an AC ripple current and has an effective value of about 3 A, so that a particularly large current capacity is not required.

FIG. 2 is a perspective view showing a connection relationship in the electric compressor driving device of the present embodiment. In FIG. 2, a circuit board 27 is a conventional circuit board 3 which is downsized by streamlining the circuit. A heat transfer device 28 for transferring heat from the inverter circuit unit 6, the reverse connection protection diode 7, and the like to the radiator is provided below the circuit board 27. The shape of the heat transfer device 28 may be any shape as long as heat can be transferred, and may not be particularly provided. The circuit board 27, the inverter circuit section 6, the reverse connection protection diode 7, the heat transfer device 28, and the like constitute one circuit block 29. The smoothing capacitor 4
The shield wire 2 is located at a position away from the circuit block 29.
6 is connected to a circuit block 29 including a circuit board 27.

FIG. 3 is a perspective side view showing the arrangement of this embodiment. In FIG. 3, the traveling motor drive device 10 and the traveling motor drive device 1 are placed in an electromagnetic wave shielding case 30.
An electrolytic capacitor as the smoothing capacitor 4 of zero, a circuit block 29 of the electric compressor driving device 11, and a smoothing capacitor 4 as a smoothing capacitor of the electric compressor driving device 11 are arranged. The circuit block 29 is closely attached to the radiator 31 so as to radiate internal heat.
The smoothing capacitor 4 cannot be arranged in the vicinity of the circuit block 29 because there is no arrangement space, and is installed on the traveling motor drive device 10.

The smoothing capacitor 4 is connected to the electric compressor driving device 11 at a remote position via a shield wire 26.
Is connected to the circuit block 29 of FIG. The radiator 31
Although not shown, it is constituted by water cooling or the like.

FIG. 4A is a perspective view showing a shielded wire structure, and FIG. 4B is a schematic view showing a magnetic field. Core wire 32
Is covered by an outer peripheral line 33. The current flowing through the core wire 32 and the current flowing through the outer peripheral line 33 flow in opposite directions, and the magnetic field 34 generated by the core current and the magnetic field 35 generated by the outer peripheral line current are in opposite directions, and cancel each other out. Thereby, the inductance value of the shield wire becomes a small value.

FIG. 5 is a characteristic diagram showing the inductance value of the wire. Lines are measured values at the same connection distance. The lead wire is two wires, the shield wire, the parallel wire, and the twisted pair wire are one wire lm, and the unit is μH. The three data shown at the top are inductance values for two lead wires, and the distance between the lead wires is 200 mm and 30 m.
m and 10 mm, respectively. According to this, the lead wire has a large inductance value and varies greatly depending on the lead wire interval. The inductance value is 1.8 at an interval of 200 mm, but the inductance value is 0.5 when the interval is closely contacted (equivalent to a parallel line), and the inductance value is 3.6.
There is a double difference. Therefore, it is difficult to specify the inductance value of the lead wire, and it is difficult to design a reliable design.

In considering the extension of the wire length, if the length is too long, the interval between the lead wires cannot be specified. Therefore, it is difficult to specify the inductance value, the surge voltage cannot be specified, and as a result, the extension is abandoned. On the other hand, the shield wire has a very small inductance value of 0.1. In addition, the distance between the core wire 32 and the outer peripheral line 33 is constant, and a reliable design with a specified inductance value is possible. As an example, when the lead wire length of the conventional product is 20 cm and the interval is 30 mm, the inductance value based on this lead wire length is considered to be an allowable value (surge voltage, DC / AC conversion loss allowable value). Therefore, since the inductance value of the shield wire is 0.1 / 1.3 for the same length, the inductance value is proportional to the length, and can be extended to 13 times, that is, 2.6 m. Also, since there is only one shield wire, 2
Workability is better than in the case of a single lead wire. The structure is not limited to the shielded wire structure shown in FIG.
A metal tube may be used instead of 3.

As described above, according to the present embodiment, the use of the shield wire instead of the lead wire enables
The wire length can be extended to about three times. By connecting the smoothing capacitor to the circuit block with a shielded wire, the smoothing capacitor and the circuit block can be separated from each other without increasing the inductance value. The degree of freedom can be increased.

(Embodiment 2) An embodiment 2 of an electric compressor driving apparatus for a vehicle according to the present invention will be described below.

FIG. 6A is a perspective view showing the structure of parallel lines, and FIG. 6B is a schematic view showing the magnetic field. FIG.
In (a), two conductive wires 37 are kept parallel by a bendable and flexible resin 36. Not limited to this shape, it can be realized by taping or passing two lead wires through a vinyl tube. In FIG. 6B, the current flowing in the right conductor and the current in the left conductor flow in opposite directions, and the magnetic field 38 generated by the current in the right conductor and the magnetic field 39 generated by the left conductor are in opposite directions, and cancel. Will fit. As a result, the inductance value of the parallel wire is small, and the closer the two conductors are, the more the canceling magnetic field increases, and the smaller the inductance value.

As shown in FIG. 5, the inductance value of the parallel wire is smaller than that of the lead wire. Further, since the distance between the two conductors 37 is constant, the inductance value is constant, and a reliable design in which the inductance value is specified is possible. As an example, conventional lead wire length 2
When extending 0 cm and the interval of 30 mm, the inductance value of the parallel wire becomes 0.6 / 1.3 for the same length. Since the inductance value is proportional to the length, it is increased by 2.6 times to 52c.
m. Also, since there is one parallel wire, workability is better than in the case of two lead wires. Also,
The wire processing is easier than the shielded wire in the first embodiment.

The shield wire in the first embodiment and the parallel wire in the present embodiment are better in terms of wire extension,
In line processing, parallel lines are better. Therefore, if the required length of the connection line is short, a parallel line may be selected, and if the length is long, a shield line may be selected.

In the above embodiment, the smoothing capacitor 4 is an electrolytic capacitor. However, the present invention is not limited to this. Further, in the above embodiment, the wire length extension using the shield wire or the parallel wire has been described.
It can also be used to improve performance and reliability, such as reducing surge voltage and DC / AC conversion loss.

Heat is also radiated to the radiator 31 from the electric compressor driving device 11, but in this case, the radiator load of the radiator 31 increases. Therefore, the traveling motor drive device 10
When the load is high, control to reduce the heat radiation of the electric compressor driving device 11 can be considered. As an example, when the traveling motor drive device 10 is under a high load, the controller of the traveling motor drive device transmits a high load signal to the air conditioning control unit 18 to reduce the output of the electric compressor drive device 11. Such control is effective when the output of the driving motor drive device 10 is relatively small, such as in a small electric vehicle or a hybrid electric vehicle. Thereby, the radiator 31
Can be shared with high reliability.

The transmission of the high-load signal to the electric compressor driving device 11 is not limited to the above-described method, but may be performed from a battery controller or without using the air conditioning controller 18. The state of high load may be, for example, climbing a hill or accelerating, and may be determined by detecting the temperature of the circuit block 29 inside the electric compressor driving device 11.

As described above, according to the present embodiment, the use of the parallel wires can provide the same effect as the case of using the shield wires.

[0041]

As apparent from the above description, the present invention comprises an inverter circuit for converting a current from a DC power supply into an AC current, and a smoothing capacitor for smoothing the current from the DC power supply to the inverter circuit. The electric compressor drive device for a vehicle provided with the electric compressor drive device for an automobile, wherein the smoothing capacitor is electrically connected to the inverter circuit via a shielded line or a parallel line, thereby providing an electric connection line for the smoothing capacitor. The inductance value can be reduced.

Therefore, even if the electric connection line of the smoothing capacitor is lengthened, it is possible to prevent an increase in surge voltage and DC / AC conversion loss, and the arrangement of the smoothing capacitor becomes free.
The degree of freedom in mounting the electric compressor drive device on a vehicle can be improved.

Further, since the distance between the different-polarity lines is fixed as compared with the case of two lead wires, the inductance value is stable.

Therefore, the inductance value can be calculated in proportion to the wire length, and the optimum design can be performed within the allowable values of the surge voltage and the DC / AC conversion loss (within the allowable value of the inductance value). It has the effect that it becomes possible.

Further, it is also possible to use the wire length as it is (with the arrangement of the smoothing capacitor as it is) for improving performance reliability such as reduction of surge voltage and DC / AC conversion loss.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing a configuration of a first embodiment of an electric compressor driving device for a vehicle according to the present invention.

FIG. 2 is a perspective view showing a connection relation in the electric compressor driving device in the embodiment.

FIG. 3 is a perspective side view showing an arrangement configuration of the embodiment.

FIG. 4A is a perspective view illustrating a configuration of a shielded wire according to the first embodiment. FIG. 4B is a schematic diagram illustrating a magnetic field generated by the shielded wire.

FIG. 5 is a characteristic diagram showing an inductance value of a wire;

FIG. 6A is a perspective view illustrating a configuration of parallel lines in the second embodiment. FIG. 6B is a schematic diagram illustrating a magnetic field based on the parallel lines.

7 (a) is a perspective view showing an external configuration of a conventional electric compressor driving device, and (b) is a perspective view showing the internal configuration.

FIG. 8 is a perspective view showing a conventional circuit board and related components.

FIG. 9 is a circuit block diagram showing an outline of a configuration of a conventional electric compressor driving device and a traveling motor driving device.

FIG. 10 is a circuit block diagram showing a configuration of a conventional electric compressor driving device.

11A is a waveform diagram illustrating an example of a current flowing into an inverter circuit. FIG. 11B is a waveform diagram illustrating a current flowing into an electric compressor driving device.

12A is a waveform diagram showing a current flowing into an inverter circuit. FIG. 12B is a waveform diagram showing a voltage applied to the inverter circuit when the inductance value is small. FIG. 12C is a waveform diagram showing a voltage applied to the inverter circuit when the inductance value is large. Waveform diagram shown

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Power supply lead wire 2 Water cooling pipe 3 Circuit board 4 Smoothing capacitor 5 Outer outline 6 Inverter circuit part 7 Reverse connection protection diode 8 Battery 9 Current supply device 9a Charging resistance 9b Main relay 10 Motor drive device for traveling 10a Inverter circuit 10b Electrolytic capacitor 11 Electric compressor drive device 12 Running motor 13 Inverter circuit 14 Electric compressor 15 12V power supply 16 Inverter control microcomputer 17 Communication circuit 18 Air conditioning control unit 19 Upper voltage dividing resistor 20 Lower voltage dividing resistor 21 Voltage detecting unit 22 Current sensor 23 Current detection Unit 24 Gate drive circuit 25 Switching power supply 26 Shield wire 27 Circuit board 28 Heat transfer device 29 Circuit block 30 Electromagnetic wave shielding case 31 Heat radiator 32 Core wire 33 Outer wire 34, 35 Magnetic field 36 Resin 37 Conductive wire 3 , 39 magnetic field

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) // B60K 6/02 ZHV B60K 9/00 ZHVC F term (reference) 3D035 AA00 5H007 AA01 AA06 BB06 CA01 CB05 CC12 DB12 DC02 DC05 HA03 5H740 BA11 BB05 BB08 BB10 MM01 MM10

Claims (1)

[Claims] 1. An automobile electric compressor driving device comprising: an inverter circuit for converting a current from a DC power supply to an AC current; and a smoothing capacitor for smoothing a current from the DC power supply to the inverter circuit. A motor-driven compressor drive for a motor vehicle, which is electrically connected to the inverter circuit via a shielded wire or a parallel wire.