JPH09207605A - Motor driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve reliability of an accelerator signal by having an accelerator sensor provided with an accelerator sensor waveform output unit for outputting sensor output and having the accelerator sensor waveform output unit integrally fitted to the control substrate of a inverter body. SOLUTION: An accelerator sensor 77 is composed of a rotary disc 87 fixed on the end of a shaft 82, a ring magnet 88 fixed on the rotary disc 87, and a hall element 89 as an accelerator sensor waveform output unit fitted to a set position opposite to the ring magnet 88 on a control substrate 90. Because the accelerator sensor 77 is stored inside an inverter case, it is not effected by the solenoid noise generated from a cable connecting a main electric power source to an electric motor or a cable connecting an electric motor controller to the electric motor or the like. Thus reliability of an accelerator signal can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor drive device.

[0002]

2. Description of the Related Art Conventionally, an electric vehicle has a motor drive unit, and an electric motor provided in the motor drive unit is a CPU
Is controlled by. When the driver depresses the accelerator pedal, the CPU generates a current command value corresponding to the depression amount of the accelerator pedal, and drives the electric motor according to the current command value.

Therefore, an electric vehicle is provided with an accelerator sensor for reading the intention of the driver, and the accelerator sensor detects the depression amount of the accelerator pedal. Further, in the accelerator sensor, a movable portion is composed of a variable resistor rotatably arranged, and the accelerator pedal and the movable portion of the variable resistor are connected by a wire.

In this case, when the driver depresses the accelerator pedal, the position of the contact attached to the movable portion of the variable resistor is rotated, and the resistance value changes. Therefore, the amount of depression of the accelerator pedal can be detected by detecting the amount of change in voltage. The accelerator signal generated by the accelerator sensor is the CPU
Then, the CPU generates a motor torque command value based on the accelerator signal, and drives the electric motor in correspondence with the motor torque command value.

The accelerator sensor can detect a change in light or the like instead of the change in the resistance value.

[0006]

However, in the conventional motor drive device, when the accelerator sensor is mounted on the electric vehicle, the cable connecting the main power supply device and the electric motor, the electric motor controller and the electric motor are connected. Electromagnetic noise is generated from the cables that are used to reduce the reliability of the accelerator signal.

By the way, the accelerator signal is of high importance because it transmits a driver's request to the electric motor controller. Therefore, it is conceivable to use a plurality of accelerator sensors in order to improve the reliability of the accelerator signal or use a shield wire as a signal line for sending the accelerator signal to the CPU, but the cost is high accordingly. turn into.

The present invention solves the problems of the conventional motor drive device, improves the reliability of the accelerator signal, and prevents the cost from increasing. The purpose is to provide.

[0009]

Therefore, in a motor drive device of the present invention, an electric motor, a motor case for housing the electric motor, an inverter main body for supplying a current to the electric motor, and the inverter main body. And an inverter case fixed to the motor case, an accelerator sensor disposed in the inverter case and actuated in accordance with a depression amount of an accelerator pedal, and an accelerator sensor drive for driving the accelerator sensor. And a department.

The accelerator sensor includes an accelerator sensor waveform output section for outputting a sensor output, and the accelerator sensor waveform output section is integrally attached to a control board of the inverter body. In another motor drive device of the present invention, the accelerator sensor drive unit is further attached to the inverter case.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of a motor drive device according to a first embodiment of the present invention. In the figure, 11 is a motor assembly, and 12 is an inverter assembly disposed on the motor assembly 11. The motor assembly 11 is a motor case 1
By accommodating the electric motor 15 in the inverter 4, the inverter assembly 12 is constituted by accommodating an inverter body (not shown) in the inverter case 16.

The motor case 14 has a saddle shape, and has a bottomed cylindrical portion 14a and a bottomed cylindrical portion 1.
A rectangular portion 14 projecting upward at both ends of 4a.
b, 14c, and a lid portion 14 that forms a motor housing chamber 18 by closing one end of the bottomed cylindrical portion 14a.
d. On the other hand, the inverter case 16 is composed of a base 16a fixed to the rectangular portions 14b and 14c via bolts (not shown) and a bottomed box-shaped portion 16b fixed to the base 16a via bolts 22.

A plurality of fins 24 are formed on the outer peripheral surface of the bottomed cylindrical portion 14a, and the fins 24 radiate the heat generated by the electric motor 15. A plurality of fins 26 are formed downward on the lower surface of the base 16a, and the fins 26 radiate the heat generated by the inverter body. A hole is formed in the center of the bottom portion of the bottomed cylindrical portion 14a and the center of the lid portion 14d, and the motor shaft 27 is disposed through the hole, and the motor shaft 27 has bearings 29, 30.
It is rotatably supported by. Also, the lid portion 14
An annular protrusion 32 is formed adjacent to the central hole of d, and the sensor chamber 34 is formed by closing the annular protrusion 32 with a lid member 33.

Further, a resolver 35 is disposed on the annular convex portion 32 so as to face the sensor chamber 34, and the resolver 3 is provided.
Reference numeral 5 detects the rotational speed of the motor shaft 27 protruding through the hole into the sensor chamber 34 and the magnetic pole position of the electric motor 15. The electric motor 15 includes a rotor 37 attached to the motor shaft 27 at substantially the center thereof, and the rotor 3 on the inner peripheral surface of the cylindrical portion of the bottomed cylindrical portion 14a.
7, a stator 38 fixed so as to face the coil 7, and a winding 39 to which the three-phase (U-phase, V-phase, and W-phase) alternating current generated in the inverter body is supplied.

The winding 39 comprises a U-phase winding, a V-phase winding and a W-phase winding, and the crimp terminals 41 of the winding 39 extend upward and are connected to the connecting member 51 in the motor case 14. To be done. On the other hand, the terminal 62 of each transistor of the inverter body is connected to the connecting member 51 in the inverter case 16. The connecting member 51 extends directly from the inside of the motor case 14 into the inside of the inverter case 16. Therefore, the outside air does not directly contact the connecting member 51.

The connecting member 51 includes a block 53 provided in the rectangular portion 14b, a spacer 54 provided between the block 53 and the lid portion 14d, and three pieces standing upward from the upper surface of the block 53. A sleeve 55 and a metal rod 56 extending vertically in the sleeve 55 and connected at the upper end to a terminal 62 of each transistor of the inverter body.
Consists of

By the way, the block 53 and the spacer 5
Both 4 and the sleeve 55 are made of an insulating material and constitute an insulating member. The block 53 electrically insulates the crimp terminal 41 from the rectangular portion 14b and accommodates each crimp terminal 41. The crimp terminals 41 are connected to the lower ends of the metal rods 56, respectively. The spacer 54 electrically insulates the crimp terminal 41 from the lid portion 14d.
It is arranged adjacent to 4d.

Further, the three sleeves 55 electrically insulate the metal rod 56 from the motor case 14 and the inverter case 16 between the motor case 14 and the inverter case 16. The rectangular portion 14b
The block 53 is fixed to the end portion of the bottomed cylindrical portion 14a by locking the block 53 to the step portion P formed in the above and pressing the block 53 and the spacer 54. can do.

As described above, since the connecting member 51 for connecting the electric motor 15 and the inverter main body is provided in the motor case 14 and the inverter case 16, the sleeve 55 can be made extremely short. Therefore,
It is possible to sufficiently suppress the generation of electromagnetic noise. In addition, the inverter case 16 is mounted at a position where the environment is not easily exposed to rainwater and the like, and a breather for eliminating an atmospheric pressure difference between the inside and the outside is provided at an appropriate place of the inverter case 16, that is, the base 16a in this embodiment. 71 is formed so that air can freely move through the breather 71.

On the other hand, a breather is not formed in the motor case 14 so that the airtightness is improved. A clearance 69 is formed between the sleeve 55 and the metal rod 56 as a communication passage for eliminating a pressure difference between the motor case 14 and the inverter case 16.
The air can move freely through 9.

When the electric motor 15 is driven, heat is generated and the air in the motor case 14 expands. When the electric motor 15 is stopped thereafter, heat is not generated and the air in the motor case 14 contracts. . At this time, the pressure in the motor case 14 tends to decrease due to the contraction of air, but between the inside of the motor case 14 and the inside of the inverter case 16 via the clearance 69 and the breather 71.
Also, since there is no pressure difference between the inside and outside of the inverter case 16, it is possible to prevent water from entering through the minute gaps of the motor case 14.

By the way, the electric motor 15 is controlled by a CPU (not shown). When the driver depresses an accelerator pedal (not shown), the CPU
Generates a current command value corresponding to the depression amount of the accelerator pedal, and drives the electric motor 15 according to the current command value. Therefore, an accelerator sensor 77 for reading the driver's intention is provided in the inverter case 16 and attached to the base 16a. Then, the accelerator sensor 77 detects the depression amount of the accelerator pedal, generates an accelerator signal corresponding to the depression amount, and sends it to the CPU.

Further, outside the inverter case 16,
A sensor drive unit 72 for driving the accelerator sensor 77 is provided and attached to the base 16a. Then, the sensor driving part 72 and the accelerator pedal are connected by a wire 75. Therefore, when the driver depresses the accelerator pedal, the wire 75 is pulled, and the sensor driving unit 72 causes the accelerator sensor 77 to move.
Is driven.

Next, the accelerator sensor 77 and the sensor driving section 72 will be described. FIG. 2 is a mounting state diagram of a sensor driving unit according to the first embodiment of the present invention, FIG. 3 is a diagram showing a coupling state of a sensor driving unit and an accelerator sensor according to the first embodiment of the present invention, and FIG. FIG. 3 is a plan view of the accelerator sensor according to the first embodiment of the present invention.

In the figure, 16 is an inverter case, 1
Reference numeral 6a is a base, and 72 is a sensor driving unit attached to the base 16a. The sensor driving unit 72 includes a bolt 8
1a, a support block 81 fixed to the base 16a, a shaft 82 rotatably supported by the support block 81, and a tip end of the shaft 82,
It is composed of an operating plate 83 and a spring 84 which are rotated together with the shaft 82. The spring 84 has one end fixed to the actuation plate 83 and the other end fixed to the support block 81, and biases the actuation plate 83 in the rotational direction toward the reference position.

The wire 7 is attached to the set position of the operating plate 83.
One end of the wire 5 is fixed, and the other end of the wire 75 is fixed to an accelerator pedal (not shown). And the wire 75
Is held by the outer tube 86, and the outer tube 8
The inside of 6 can be moved. The outer tube 86 is fixed to the base 16a by a bracket 85.

The shaft 82 extends upward through the base 16a, and the accelerator sensor 77 is arranged at the tip. The accelerator sensor 77 includes a rotating disc 87 fixed to the tip of the shaft 82, a ring magnet 88 fixed to the rotating disc 87, and a control board 90.
It is composed of a Hall element 89 as an accelerator sensor waveform output unit attached at a setting position facing the ring magnet 88 above. The ring magnet 88 is magnetized with a sinusoidal waveform, and the Hall element 89 detects the absolute position of the operating plate 83 based on the waveform. In addition, the rotation angle of the operating plate 83 is set to be smaller than 180 [°].
Are regulated so as to fit within the R-R region.

Next, the control circuit of the motor drive device having the above-mentioned structure will be described. FIG. 5 is a control circuit diagram of the motor drive device according to the first embodiment of the present invention. In the figure, 15 is an electric motor, 74 is a CPU that generates a motor torque command value based on the vehicle speed, the amount of depression of an accelerator pedal (not shown), and 73 is a pulse width modulation based on the motor torque command value generated by the CPU 74. An electric motor controller that sends a signal to the inverter of the electric motor 15 to drive the electric motor 15, 75 is a vehicle speed sensor that detects the vehicle speed of the electric vehicle, 76 is a brake sensor that detects the depression amount of a brake pedal (not shown), and 77 is an accelerator. It is a sensor.

When the accelerator sensor 77 detects the depression amount of the accelerator pedal and generates an accelerator signal, the accelerator signal is sent to the CPU 74. The CPU
74 generates a motor torque command value based on the vehicle speed sent from the vehicle speed sensor 75 and the depression amount of the accelerator pedal sent from the accelerator sensor 77, and sends the motor torque command value to the electric motor controller 73. The electric motor controller 73 receives the motor torque command value, generates a pulse width modulation signal, turns on / off the inverter of the electric motor 15 on the basis of the pulse width modulation signal, and causes each winding 39 (FIG. 1) to rotate. Sends phase current.

Next, the sensor waveform output circuit of the hall element 89 (FIG. 3) will be described. FIG. 6 is a sensor waveform output circuit diagram according to the first embodiment of the present invention, and FIG. 7 is a characteristic diagram of an amplifier circuit according to the first embodiment of the present invention.
In FIG. 7, the abscissa represents the depression amount of an accelerator pedal (not shown), and the ordinate represents the sensor output of the hall element 89.

In the figure, 89 is a hall element, 99 is a constant voltage circuit for applying an operating voltage to the hall element 89, 91 is an amplifier circuit, and C is a capacitor. The sensor output of the hall element 89 is -5 [V] when the accelerator pedal depression amount is 0, 0 [V] when the accelerator pedal depression amount is 50 [%], and the accelerator pedal depression amount. Is set to +5 [V] when is 100 [%].

Thus, the accelerator sensor 77 (FIG. 5)
Is housed in the inverter case 16 (FIG. 1), electromagnetic noise is generated from a cable connecting the main power supply device (not shown) to the electric motor 15, a cable connecting the electric motor controller 73 to the electric motor 15, and the like. However, it is not affected by it. Therefore, the reliability of the accelerator signal can be improved. Moreover, since it is not necessary to use a plurality of accelerator sensors 77, it is possible to prevent the cost from increasing.

Further, since the Hall element 89 is attached to the control board 90 (FIG. 3), the accelerator signal can be directly sent to the CPU 74 on the control board 90. As a result, it is not necessary to dispose a signal line between the hall element 89 and the CPU 74, so that disconnection does not occur and the reliability of the sensor waveform output circuit can be improved. Further, since it is not necessary to use a shield line as a signal line for sending the accelerator signal to the CPU 74, it is possible to prevent the cost from increasing.

Further, since the accelerator sensor 77 is arranged in the inverter case 16, it is possible to prevent drip. Next, a second embodiment of the present invention will be described. FIG. 8 is a plan view of an accelerator sensor according to the second embodiment of the present invention. In the figure, 93 is an accelerator sensor, 87 is a rotating disk, 94 is a ring magnet, and 95 is a magnet for detecting the origin position.

In this case, the number of poles of the ring magnet 94 is increased and a hall element (not shown) corresponding to each magnetic pole is provided.

[0036]

As described in detail above, according to the present invention, in a motor drive device, an electric motor, a motor case for housing the electric motor, and an inverter main body for supplying a current to the electric motor. , An inverter case fixed to the motor case while accommodating the inverter main body, an accelerator sensor disposed in the inverter case and operated in accordance with a depression amount of an accelerator pedal, and driving the accelerator sensor And an accelerator sensor driving unit that operates.

The accelerator sensor includes an accelerator sensor waveform output section for outputting a sensor output, and the accelerator sensor waveform output section is integrally attached to the control board of the inverter body. In this case, since the accelerator sensor is housed in the inverter case, even if electromagnetic noise occurs from the cable connecting the main power supply device and the electric motor, the cable connecting the electric motor controller and the electric motor, etc. I will not receive it.

Therefore, the reliability of the accelerator signal can be improved. Moreover, since it is not necessary to use a plurality of accelerator sensors, it is possible to prevent the cost from increasing. Further, since the accelerator sensor is housed in the inverter case, drip-proof can be achieved.

The accelerator signal is sent to the CPU on the control board.
Since it can be directly sent to, it is not necessary to provide a signal line. Therefore, disconnection etc. does not occur,
The reliability of the sensor waveform output circuit can be improved. Since it is not necessary to use a shield line as a signal line for sending an accelerator signal to the CPU, it is possible to prevent the cost from increasing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a motor drive device according to a first embodiment of the present invention.

FIG. 2 is an attachment state diagram of a sensor driving unit according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a connected state of a sensor driving unit and an accelerator sensor according to the first embodiment of the present invention.

FIG. 4 is a plan view of the accelerator sensor according to the first embodiment of the present invention.

FIG. 5 is a control circuit diagram of the motor drive device according to the first embodiment of the present invention.

FIG. 6 is a sensor waveform output circuit diagram according to the first embodiment of the present invention.

FIG. 7 is a characteristic diagram of the amplifier circuit according to the first embodiment of the present invention.

FIG. 8 is a plan view of an accelerator sensor according to a second embodiment of the present invention.

[Explanation of symbols]

 14 motor case 15 electric motor 16 inverter case 77, 93 accelerator sensor 89 hall element

Claims (2)

[Claims] 1. An electric motor, a motor case for accommodating the electric motor, an inverter main body for supplying a current to the electric motor, and an accommodating the inverter main body,
An inverter case fixed to the motor case, an accelerator sensor that is disposed in the inverter case and is operated in accordance with the amount of depression of an accelerator pedal, and an accelerator sensor drive unit that drives the accelerator sensor are provided. The motor drive device, wherein the accelerator sensor includes an accelerator sensor waveform output unit that outputs a sensor output, and the accelerator sensor waveform output unit is integrally attached to a control board of the inverter body. 2. The motor drive device according to claim 1, wherein the accelerator sensor drive unit is attached to the inverter case.