JP3407485B2 - Inverter device and transistor module with current sensor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter device and a transistor module with a current sensor.

[0002]

2. Description of the Related Art Conventionally, an electric vehicle uses a motor composed of a rotor and a stator coil,
The motor is driven by supplying a current controlled by a motor driving device to the stator coil. In this case, the motor drive device has a current waveform control circuit and a base drive circuit. Then, in the current waveform control circuit, a three-phase sine wave signal composed of a U phase, a V phase, and a W phase is generated corresponding to the magnetic pole position of the rotor, and a current command value is generated to generate a sine wave. Based on the signal and the current command value, a three-phase pulse width modulation (PWM) signal having a pulse width corresponding to the current command value is sent to the base drive circuit.

The base drive circuit generates a transistor drive signal corresponding to the pulse width modulation signal,
Output to the inverter. The inverter has six transistors, turns on the transistors only while the transistor drive signal is on, generates phase currents of three phases, and supplies the phase currents to the stator coil. Then, the phase current of two of the three phases is detected by the current sensor and feedback control is performed.

By the way, the six transistors form a transistor module by connecting one pair in series, and each transistor module, a capacitor for smoothing a voltage applied by a power source, a power cable, etc. They are electrically connected to each other via a bus panel. FIG. 2 is a side view of a conventional transistor module.

In the figure, 15 is a heat sink, and 21 is a transistor module mounted on the heat sink 15. In addition to the transistor module 21, two transistor modules (not shown) are mounted on the heat sink 15. Here, only the transistor module 21 will be described. The transistor module 21 incorporates a pair of transistors (not shown) and has a positive electrode side terminal 21a, a negative electrode side terminal 21b, and an output terminal 21c.

Then, the transistor module 21
The output terminal 21c is connected to a bus bar 25 made of an elongated copper plate on the output side, and a motor connecting cable assembly (not shown) is connected to the bus bar 25. Therefore, the output current generated in the transistor module 21 is supplied to the stator coil of the motor (not shown) as a phase current. Here, as described above, the current sensor 51 can detect the phase current.

In this case, the current sensor 51 is composed of, for example, a core (not shown) surrounding the bus bar 25, a Hall element arranged in a gap of the core, and the like, and a phase current flows through the bus bar 25. The phase current is detected by the change of the magnetic flux. Therefore, the current sensor 51 is fixed to the bus bar 25 by the bolt 55. Further, the current sensor 51 can be fixed to an inverter frame or the like (not shown).

[0008]

However, in the above-mentioned conventional transistor module, the current sensor 5 is used.
In order to fix 1 to the bus bar 25, the inverter frame, or the like, it is necessary to perform a drilling process on the bus bar 25 or the inverter frame, which increases the number of processing steps.

When fixing the current sensor 51 to the bus bar 25, after fixing the current sensor 51 to the bus bar 25, the bus bar 25 is fixed to the transistor module 21.
Since it is necessary to fix it to, the number of assembling steps will increase. When fixing the current sensor 51 to the inverter frame, after fixing the current sensor 51 to the inverter frame, the bus bar 25 is provided in the current sensor 51.
Alternatively, since it is necessary to pass the copper cable, the number of assembling steps is increased.

Further, when the bus bar 25 is extended horizontally from the transistor module 21, the current sensor 51 fixed to the bus bar 25 interferes with another member, for example, a resistor. Therefore, the bus bar 25 is bent and a heat sink is formed. It is necessary to keep a certain distance between the upper surface of 15 and the lower surface of the current sensor 51. Therefore, the size of the inverter device increases accordingly.

Moreover, by bending the bus bar 25 and by increasing the distance from the output terminal 21c to the motor connecting cable assembly, the electrical balance between the transistor modules 21 becomes poor. . The present invention solves the problems of the conventional transistor module described above, and can reduce the number of processing steps and the number of assembly steps, and provide an inverter device and a transistor module with a current sensor that do not require bending of the bus bar. The purpose is to

[0012]

To this end, in the inverter device of the present invention, a transistor module comprising a pair of transistors that are turned on and off by the switching means, each having a positive electrode side terminal, a negative electrode side terminal and an output terminal. And a bus bar fixed to the output terminal for allowing an output current to flow, and a current sensor for measuring an output current flowing through the bus bar. The current sensor is built in the transistor module so as to surround the outer peripheral edge of the output terminal.

[0013]

[0014]

In the transistor module with a current sensor according to the present invention, a transistor module comprising a pair of transistors which are turned on and off by switching means, each having a positive electrode side terminal, a negative electrode side terminal and an output terminal, and the output terminal A current sensor for measuring the output current flowing through the fixed bus bar. The current sensor is built in the transistor module so as to surround the outer peripheral edge of the output terminal.

[0016]

[0017]

[0018]

[0019]

According to the present invention, as described above, the inverter device comprises a pair of transistors that are turned on and off by the switching means, and has a positive side terminal, a negative side terminal and an output terminal. It has a transistor module, a bus bar fixed to the output terminal for allowing an output current to flow, and a current sensor for measuring an output current flowing through the bus bar. The current sensor is built in the transistor module so as to surround the outer peripheral edge of the output terminal.

In this case, in order to arrange the current sensor,
Since it is not necessary to drill holes in the bus bar, inverter frame, etc., the number of processing steps can be reduced. Further, since it is not necessary to fix the current sensor to the transistor module with a bolt or the like, the number of assembling steps of the inverter device can be reduced. Furthermore, since the current sensor is built in the transistor module, it does not interfere with other members such as resistors. Therefore, you can extend the busbar horizontally from the transistor module,
The size of the inverter device can be reduced.

Further, in the horizontal direction of the transistor module, the bus bar can be connected in any direction of 360 [°] from the output terminal.

[0022]

[0023]

[0024]

[0025]

In the transistor module with a current sensor of the present invention, a transistor module comprising a pair of transistors that are turned on and off by switching means, each having a positive electrode side terminal, a negative electrode side terminal and an output terminal, and the output terminal A current sensor for measuring the output current flowing through the fixed bus bar. The current sensor is built in the transistor module so as to surround the outer peripheral edge of the output terminal.

In this case, in order to arrange the current sensor,
Since it is not necessary to drill holes in the bus bar, inverter frame, etc., the number of processing steps can be reduced. Furthermore, since the current sensor is built in the transistor module, it does not interfere with other members such as resistors. Therefore, the bus bar can be extended horizontally from the transistor module, and the size of the inverter device can be reduced.

Further, in the horizontal direction of the transistor module, the bus bar can be connected in any direction of 360 [°] from the output terminal.

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 3 is a diagram showing a drive device for an electric vehicle in a first example which is a premise for explaining the present invention. In the figure, 31 is a motor, and the motor 31 is arranged in each of the four drive wheels of the electric vehicle, and is driven by the current supplied from the DC power supply 33. The motor 31 includes a rotor (not shown) made of a permanent magnet having 6 poles and a stator coil (not shown) made of a winding of three phases.

A rotor of the resolver 35 is coaxially coupled to the rotor shaft 34 of the motor 31,
The magnetic pole position of the rotor of the motor 31 can be detected. Further, a resolver circuit 36 is connected to the resolver 35, and the resolver circuit 36 is
AC voltage x (= E _m sin ωt), y is applied to the resolver 35.
(= E _m cos ωt) is applied and the resolver 35
From AC voltage resolver signal a (= E _m sin (ωt + θ)
), The magnetic pole position is detected, and the magnetic pole position signal b is output to the current waveform control circuit 37.

The current waveform control circuit 37 also generates a three-phase pulse width modulation signal d having a duty ratio corresponding to the current command value, and outputs the pulse width modulation signal d to the base drive circuit 38. . The base drive circuit 38 receives the pulse width modulation signal d output from the current waveform control circuit 37, generates a transistor drive signal c for driving each of the six transistors Tr, and supplies the transistor drive signal c to the inverter 40. Output. The current waveform control circuit 37 and the base drive circuit 38 constitute a switching means.

The stator coil of the motor 31 is excited by the inverter 40. The inverter 40 includes the six transistors Tr, three snubber circuits 41, and two capacitors 13 and 14, and the transistor drive signal c is provided at the base of each transistor Tr.
Is entered. Then, a pair of transistors Tr are connected in series to form transistor modules 21 to 23, and the inverter 40 is formed by connecting three transistor modules 21 to 23 in parallel.

Further, 49 is a main computer, 51 is a current sensor for detecting a phase current supplied to the motor 31, 53 is a power supply circuit connected to the DC power supply 33, and the power supply circuit 53 is the inverter 40. Is applied to the current waveform control circuit 37 and the like, and the control power supply voltage r is applied to the current waveform control circuit 37 and the like. FIG. 4 is a perspective view of the inverter device in the first example which is a premise for explaining the present invention.

In the figure, 11 is a control board, 12 is a bus panel formed by sandwiching an insulator between the positive and negative bus bars, 13 and 14 are smoothing capacitors, and 15 is a heat sink. The capacitor 1
3, 14 are connected in parallel to increase the capacity.
Further, three transistor modules (not shown) are sandwiched between the bus panel 12 and the heat sink 15, and a voltage is applied to each transistor of the transistor module via the bus panel 12. Then, the heat generated by turning on / off each transistor is radiated by the heat sink 15.

Next, the transistor modules 21-
23 will be described. In this case, since the transistor modules 22 and 23 have the same structure as the transistor module 21, only the transistor module 21 will be described. FIG. 1 is a perspective view of a transistor module in a first example which is a premise for explaining the present invention,
FIG. 5 is a side view of the transistor module in the first example, which is a premise for explaining the present invention.

In the figure, 15 is a heat sink, and 21 is a transistor module mounted on the heat sink 15. In addition to the transistor module 21, two transistor modules 22 and 23 (FIG. 3) are mounted on the heat sink 15. The transistor module 21 incorporates a pair of transistors (not shown) and has a positive electrode side terminal 21a, a negative electrode side terminal 21b, and an output terminal 21c. The positive electrode side terminal 21
Each of the a, the negative electrode side terminal 21b, and the output terminal 21c has a quadrangular shape.

Then, the transistor module 21
An output-side bus bar 25 made of a long plate made of copper is connected to the output terminal 21c, and a motor connecting cable assembly (not shown) is connected to the bus bar 25. Therefore, the output current generated in the transistor module 21 is supplied to the stator coil of the motor as a phase current. Here, as described above, the phase current can be detected by the current sensor 71.

In this case, the current sensor 71 is composed of, for example, a core (not shown) surrounding the bus bar 25, a Hall element arranged in a gap of the core, and the like, and a phase current flows through the bus bar 25. The phase current is detected by the change of the magnetic flux. To this end, the current sensor 71 is composed of a rectangular annular body 72, and a detection hole 73 for passing the bus bar 25 is formed in the rectangular annular body 72. In this case, the detection hole 73
The bottom surface of the output terminal 21c is set to be lower than the upper surface of the output terminal 21c, and the upper surface of the detection hole 73 is set to be higher than the upper surface of the output terminal 21c plus the thickness of the bus bar 25. Then, the guide 60 is projected along one side of the rectangular annular body 72 along the transistor module 21. Therefore, since the "L" portion is formed by the rectangular annular body 72 and the guide 60, the current sensor 71 can be positioned by applying the "L" portion to the corner portion of the output terminal 21c. .

The current sensor 71 is fixed to the transistor module 21 at only one point by screwing the bolt 61 into the screw hole formed in the guide 60. Therefore, the number of assembling steps of the inverter device can be reduced. In addition, the current sensor 7
Since the bus bar 25, the inverter frame and the like do not need to be drilled in order to dispose 1, the number of processing steps can be reduced.

Further, since the current sensor 71 is fixed on the transistor module 21, it does not interfere with other members such as resistors. Therefore, the bus bar 25 can be horizontally extended from the transistor module 21, and the size of the inverter device can be reduced.
Moreover, since it is not necessary to bend the bus bar 25 and the distance from the output terminal 21c to the motor connecting cable assembly can be shortened, the electrical balance between the transistor modules 21 to 23 is improved. be able to.

Further, since the current sensor 71 is detachably arranged by the bolt 61, the current sensor 71 is attached to only two transistor modules of the three transistor modules 21 to 23, and the phase current of two phases is attached. Can be detected. Next, a second example, which is a premise for explaining the present invention, will be described. FIG. 6 is a perspective view of a transistor module in a second example which is a premise for explaining the present invention. In addition, about the thing which has the same structure as a 1st example, the description is abbreviate | omitted by giving the same code | symbol.

In this case, the current sensor 75 is formed integrally with the transistor module 21. Therefore, it is not necessary to fix the current sensor 75 to the transistor module 21 with a bolt or the like, and the number of assembling steps of the inverter device can be reduced. Next, examples of the present invention will be described.

FIG. 7 is a perspective view of a transistor module according to an embodiment of the present invention. In addition, about the thing which has the same structure as a 1st example, the description is abbreviate | omitted by giving the same code | symbol. In this case, the output terminal 21c
A current sensor 76 is formed on the outer peripheral edge of the. Therefore,
Since the current sensor 76 is built in the output terminal 21c,
In the horizontal direction of the transistor module 21, the bus bar 25 (FIG. 5) can be connected in any direction from the output terminal 21c to 360 [°].

Next, a third example, which is a premise for explaining the present invention, will be described. FIG. 8 is a perspective view of a transistor module in a third example which is a premise for explaining the present invention. In addition, about the thing which has the same structure as a 1st example, the description is abbreviate | omitted by giving the same code | symbol. In this case, the current sensor 77 and the output terminal 21c are formed separately, and the detection hole 73 of the current sensor 77 is formed.
An output terminal 21c is provided in (FIG. 1). Then, a part of the outer peripheral edge of the current sensor 77 is projected along the transistor module 21 to form the mounting portion 78. In the current sensor 77, a bolt 79 is screwed into a screw hole (not shown) formed in the mounting portion 78,
It is fixed to the transistor module 21 at only one point.
Therefore, the number of assembling steps of the inverter device can be reduced.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a perspective view of a transistor module in a first example which is a premise for explaining the present invention.

FIG. 2 is a side view of a conventional transistor module.

FIG. 3 is a diagram showing a drive device for an electric vehicle in a first example, which is a premise for explaining the present invention.

FIG. 4 is a perspective view of an inverter device in a first example which is a premise for explaining the present invention.

FIG. 5 is a side view of a transistor module in a first example which is a premise for explaining the present invention.

FIG. 6 is a perspective view of a transistor module in a second example which is a premise for explaining the present invention.

FIG. 7 is a perspective view of a transistor module according to an embodiment of the present invention.

FIG. 8 is a perspective view of a transistor module in a third example which is a premise for explaining the present invention.

[Explanation of symbols]

21-23 Transistor module 25 bus bars 37 Current waveform control circuit 38 Base drive circuit 60 guides 71, 75, 76, 77 Current sensor 73 Detection hole

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI H02P 7/63 302 H02P 7/63 302C (72) Inventor Kimiya Maki 10 Takane, Fujii-cho, Anjo-shi, Aichi Aisin Ai W Co., Ltd. (56) Reference Japanese Unexamined Patent Publication No. 6-335118 (JP, A) Actually opened 64-37388 (JP, U) Actually opened 3-120019 (JP, U) Actually opened 63-10787 (JP , U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02M 7/48 G05F 1/10 H02M 7/04 H02M 7/5387 H02P 7/63

Claims (2)

(57) [Claims] 1. A transistor module comprising a pair of transistors that are turned on and off by a switching means, each having a positive electrode side terminal, a negative electrode side terminal and an output terminal; and a transistor module fixed to the output terminal for supplying an output current. and the bus bar, which has a current sensor for measuring an output current flowing through the bus bar, said current sensor,
An inverter device, which is built in the transistor module so as to surround an outer peripheral edge of the output terminal . 2. A transistor module comprising a pair of transistors which are turned on and off by a switching means, each having a positive electrode side terminal, a negative electrode side terminal and an output terminal, and an output current flowing through a bus bar fixed to the output terminal. With a current sensor to measure,
The transistor module with a current sensor, wherein the current sensor is built in the transistor module so as to surround an outer peripheral edge of the output terminal .