KR20160032352A - Apparatus for applying an electric current control of motor - Google Patents

Abstract

An invention of an energization control device for a motor is disclosed. A motor control device for a motor according to the present invention includes a motor including a first coil for each phase and a second coil connected in series to the first coil, a motor drive unit for driving the motor by switching each phase through a plurality of inverter switches, And a current sensor for sensing a current state applied to the first coil and the second coil. A switch unit and a current sensor, which are connected in series, are operable to select a current path for at least one of the first coil and the second coil. And a drive control unit for controlling the operation of the switch unit according to the detection of the switch unit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an electric current control apparatus for a motor,

[0001] The present invention relates to an electric current control apparatus for a motor, and more particularly, to an electric power steering (EPS) system in which an electric power steering (EPS) system is provided with a switch for wire switching, To thereby ensure fail-safe against a motor failure.

The electric power steering (EPS) device provides steering convenience to the driver by boosting the steering force generated by the brushless motor through the decelerator to provide steering force to the steering wheel. This device is more fuel-efficient than the hydraulic power steering, It is good and has a small volume, so it is widely applied to automobiles. Until a few years ago most electric power steering systems were mainly permanent magnet DC motors with easy control and simple hardware structure. Recently, however, BLAC (Brushless AC) motors with high efficiency and long life have been applied.

Generally, three-phase BLAC motors are sequentially wound in respective slots, and two terminals are connected to neutral points on the ECU and the motor 3, respectively. When a coil is burned in one of the slots, a current does not normally flow to the motor, Is not generated.

In other words, when the motor fails due to the disconnection of the motor coil or the contact failure of the power supply terminal, the ECU stops the motor control, so that the motor rotational force is not generated in the column. As a result, the driver is burdened with a sudden steering torque, Can occur.

In addition, Steer By Wire, a next-generation steering system, requires a fail-safe structure for the failure of the drive motor or ECU because the steering wheel and the motor drive are constructed without a mechanical connection.

Therefore, in some systems, a fail-safe structure such as adding a motor and an ECU to provide a 1/2 steering force in the event of a motor or ECU damage has been proposed. However, such a structure has a problem in that a material cost is increased and a weight is increased There was a problem.

BACKGROUND ART [0002] The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2013-0110772 (published on Mar. 10, 2013, entitled "3-wire stator and BLDC motor using the same").

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric power steering (EPS) system in which a switch for switching wiring to an ECU is provided, And to select a current path so that the energized state is changed, thereby ensuring fail-safe against a motor failure.

It is another object of the present invention to provide a three-phase BLAC motor in which a current path is selected so that current is only energized in a coil of a slot in which no burning has occurred through switch control even if coil burn- To thereby generate torque continuously in the motor.

A motor control device for a motor according to the present invention includes: a motor including a first coil for each phase and a second coil connected in series to the first coil; A motor driving unit for driving the motor by switching the phases by a plurality of inverter switches; A current sensor for sensing a current state applied to the first coil and the second coil; A switch unit in which a plurality of switches are connected in series so that a current path for the at least one of the first coil and the second coil is selected; And a drive control unit for controlling the operation of the switch unit according to the detection of the current sensor. And a control unit.

In the present invention, the motor includes three rotors having a plurality of slots in a radial pattern, three phases A, B, and C in the stator having the number of slots of 3 x (2n + 4), (n = B, and C coils are wound in slots at positions of 360 x 2 n, 360 x 2 n + 120, and 360 x 2 n + 240 (n = 0, 1, 2 ... n) And the coils are wound on the slots at the positions of 360 占 (2n + 1), 360 占 (2n + 1) +120, 360 占 (2n + 1) +240 (n = 0,1,2 ... n) And a second coil.

In the present invention, the drive control unit controls the operation of the switch unit so that current paths for the first and second coils are selected if the first and second coils are not burned out from the current sensor .

In the present invention, when the burnout of any one of the first and second coils is detected from the current sensor, the drive control unit selects the current for the coil whose burnout has not been detected, And the operation of the switch unit is controlled so that the path is selected.

In the electric power steering (EPS) system according to the present invention, an electric power steering (EPS) system is provided with a switch for switching the connection to the ECU so that a current path is selected so that the energized state of the motor wound in series through the switch control is changed Fail safe can be ensured for a motor failure.

In the present invention, the current path is selected so that current is only energized in a coil of a slot in which no burn-out is caused through switch control even if coil burn-out occurs in any slot in a three-phase BLAC motor by changing the winding structure, So that torque can be generated.

In addition, the present invention can reduce the cost and increase the weight because the motor can be switched over only by switch control without adding a motor or an ECU in the fail-safe implementation.

Fig. 1 is a circuit diagram showing the driving of the BLAC motor.
2 is a block diagram showing an energization control apparatus for a motor according to an embodiment of the present invention.
3 is a circuit configuration diagram showing an energization control apparatus for a motor according to an embodiment of the present invention.
4 is a view showing a winding structure of a motor in a current control apparatus for a motor according to an embodiment of the present invention.
5 is a view for explaining a case where the motor winding is not damaged in the energization control apparatus of the motor according to the embodiment of the present invention.
6 to 7 are diagrams for explaining a case where the motor winding is burned in the energization control apparatus of the motor according to the embodiment of the present invention.
FIG. 8 is a graph comparing torque generated in the motor when the motor winding is burned and not burned in the motor current control apparatus according to the embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an energization control apparatus for a motor according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this process, the thicknesses of the lines and the sizes of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

Further, the terms described below are defined in consideration of the functions of the present invention, which may vary depending on the intention or custom of the user, the operator. Therefore, definitions of these terms should be made based on the contents throughout this specification.

First, FIG. 1 is a circuit diagram showing a BLAC motor driving.

A typical BLAC motor drives six steps through inverters (Q1 to Q6). Figure 1 shows the driving of the first step. The first inverter switch (Q1) and the second inverter switch (Q2) And an operation example according to an embodiment of the present invention will be described with reference to a first step as shown in FIG.

Also, in the case of the three-phase BLAC motor, the windings are symmetrically connected to the phases A, B, and C, respectively. In the present invention,

FIG. 2 is a block diagram showing a current control device for a motor according to an embodiment of the present invention, FIG. 3 is a circuit diagram showing a current control device for a motor according to an embodiment of the present invention, FIG. 5 is a view for explaining a case where the motor winding is not damaged in the motor current control apparatus according to the embodiment of the present invention. FIG. 6 to 7 are views for explaining a case where a motor winding is burned in an energization control apparatus for a motor according to an embodiment of the present invention, FIG. 5 is a graph comparing torque generated in the motor when the motor winding is burned and not burned in the control device. FIG.

2 to 7, the motor current control device includes a motor 10, a motor drive unit 20, a current sensor 30, a switch unit 40, and a drive control unit 50 ).

The motor 10 includes a rotor having a plurality of slots radially arranged therein and a stator having a number of slots of 3 x (2n + 4), (n = 0, 1, 2 ... n) The first coil and the coil of each phase wound on the slots at the positions of 360 占 2n, 360 占 2n + 120 and 360 占 2n + 240 (n = 0, 1, 2 ... n) (2n + 1) +240 (n = 0, 1, 2 ... n) for each 360 x (2n + 1), 360 x do.

In other words, in the case of a rotor having a plurality of slots in a radial manner and a 12-slot stator having n = 0 in a 3 × (2n + 4) slot as shown in FIG. 4, , The phase A is wound on the slots # 1 and # 7 corresponding to the electric angle of 360 × 2n (n = 0,1) and the phase B is wound on the electrical angle 360 × 2n + 120 (n = 0,1) And the C phase is wound on the corresponding slots # 2 and # 8, and the first coil wound on the slots # 3 and # 9 corresponding to the electric angle of 360 × 2n + 240 (n = , And the phase A is wound in the slots # 4 and # 10 corresponding to the electric angle of 360 × (2n + 1) (n = 0,1), the phase B is 360 × 2n + (# 5, # 11) corresponding to the electrical angle of 120 (n = 0, 1) and the C phase is wound on the slot # , ≪ / RTI ># 12).

More specifically, as shown in FIG. 4, after the coils are wound on the slot # 1, the electrical angle is 720 degrees, that is, 180 degrees mechanically (electric angle in the motor = number of poles / 2 * And the first coil is formed by connecting the current sensor 30 through the connection terminal Am to the slot # 7 which is symmetrically positioned. After the coil is continuously wound on the slot # 4, the coil is wound on the slot # 10 having an electrical angle of 720 degrees, that is, mechanically 180 degrees symmetrically, to form the connection terminal Ae to form the second coil. Thus, the first coil and the second coil are connected in series through the connection terminals Am and Am '.

The motor driving unit 20 drives the motor 10 by switching each phase of the motor 10 through a plurality of inverter switches Q1 to Q2.

The current sensor 30 senses the current state applied to the first and second coils.

The switch unit 40 is connected in parallel with a plurality of switches SW1 to SW5 that are operated to select a current path for one or more coils of the first coil and the second coil.

The drive control unit 50 controls the switch unit 40 according to the detection of the current sensor 30. [

At this time, the drive control unit 50 controls the switch unit 40 according to the burn-out of the coil to control the current applied to the burned-in coil. In the present invention, the drive control unit 50 will be divided into three cases.

First, when the burnout of the first and second coils is not detected from the current sensor 30, the drive control unit 50 controls the operation of the switch unit 40 so that the current paths for the first and second coils are selected . Therefore, in the first step, SW1, SW3, SW4, and S5 of the switch unit 40 are turned off, and the terminals connected to the lines # 1 to # 9 are in the same potential state as Vs to turn on the switch SW2 5, and a torque of 100% is generated as shown in the CASE1 graph of Fig.

Second, when the burnout of the first coil is sensed from the current sensor 30, the drive control unit 50 bypasses the first coil and controls the switch unit 40 so that the current path for the second coil is selected. Therefore, in the first step, SW1 and SW4 of the switch unit 40 are turned off, and the terminals connected to the lines # 5 to # 9 are in the same potential state as Vs, so that the current is not energized and SW2, SW3 and SW5 are turned on , The first coil is bypassed and only the second coil is energized as shown in FIG. 6, so that a three-phase balanced torque of 50% occurs as shown in the CASE2 graph of FIG.

Third, when burnout of the second coil is detected from the current sensor 30, the drive control unit 50 bypasses the second coil and controls the switch unit 40 so that the current path for the first coil is selected. Therefore, in the first step, the switches SW2 to SW5 of the switch unit 40 are turned off so that the terminals connected to the lines # 1 to # 6 and the lines # 10 to # 12 are in the same potential state as Vs, SW1 is turned on to bypass the second coil as shown in Fig. 7, and only the first coil is energized, so that a 3-phase balanced torque of 50% occurs as shown in the CASE3 graph of Fig.

As described above, in the electric power steering (EPS) system of the motor according to the embodiment of the present invention, the electric power steering (EPS) system includes a switch for switching the connection to the ECU, By selecting the current path so that the state is changed, fail-safe against motor failure can be ensured.

In addition, by changing the winding structure, even if a coil is burned in any one slot of the three-phase BLAC motor, the current path is selected so that current is only energized in the coil of the slot where no burn- .

In addition, in the fail safe implementation, it is possible to switch the motor connection by only switch control without adding a motor or an ECU, so that cost reduction and weight increase can be prevented.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined by the appended claims. will be. Accordingly, the true scope of the present invention should be determined by the following claims.

10: motor 20: motor driving section
30: current sensor 40: switch section
50:

Claims (4)

A motor including a first coil for each phase and a second coil connected in series to the first coil;
A motor driving unit for driving the motor by switching the phases by a plurality of inverter switches;
A current sensor for sensing a current state applied to the first coil and the second coil;
A switch unit in which a plurality of switches are connected in series so that a current path for the at least one of the first coil and the second coil is selected; And
A drive control unit for controlling the operation of the switch unit according to the detection of the current sensor; And a control unit for controlling the motor.
The motor drive apparatus according to claim 1, wherein the motor
A coil having three phases of A, B and C in a stator having a plurality of slots in a radial shape, a stator having the number of slots of 3x (2n + 4), and n slots (n = 0, 1, 2 ... n) The first coil and the coil of each phase wound on slots in the positions of electrical angles 360 x 2 n, 360 x 2 n + 120, and 360 x 2 n + 240 (n = 0, 1, 2 ... n) (2n + 1), 360 占 (2n + 1) +120, and 360 占 (2n + 1) +240 (n = 0,1,2 ... n) And a control unit for controlling the energization of the motor.
The apparatus of claim 1, wherein the drive control unit
And controls the operation of the switch unit so that a current path for the first coil and the second coil is selected if burnout of the first coil and the second coil is not detected from the current sensor.
The apparatus of claim 1, wherein the drive control unit
Wherein when the burnout of any one of the first and second coils is detected from the current sensor, burnout is selected to bypass the detected coil, and the operation of the switch portion is selected such that a current path for the coil, Of the motor (1).

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