JP2017036001A5 - - Google Patents

Description

It is a figure showing an example of 1 composition of vehicles concerning an embodiment of the present invention. It is a schematic structure figure showing a torque sensor concerning an embodiment of the present invention. It is sectional drawing which shows the structure of the three-phase electric motor which concerns on embodiment of this invention. It is a schematic diagram which shows the winding structure of the three-phase electric motor of FIG. It is a circuit diagram which shows the specific structure of the motor control apparatus which concerns on embodiment of this invention. It is a characteristic diagram which shows the relationship between the steering torque at the time of normal, and a steering auxiliary current command value. It is a characteristic diagram which shows the relationship between the steering torque at the time of abnormality, and a steering auxiliary current command value. It is a block diagram which shows the specific structure of the motor electrical angle detection circuit which concerns on embodiment of this invention. It is a block diagram which shows the specific structure of the relative offset amount estimation part which concerns on embodiment of this invention. It is a wave form diagram explaining the relationship between the origin of a motor electrical angle, and the reference value of an output-shaft rotation angle detected value . (A) is a wave form diagram which shows an example of the torque command value for estimating a motor electrical angle origin, (b) and (c) are the time of inputting the drive current by a step-wave-like command value to an electric motor. It is a wave form diagram which shows an example of the response waveform of an output torque.

Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. The drawings are schematic, relationships and ratios, etc. of dimensions and the like should be noted in particular may be different from actual ones.
Further, the following embodiments exemplify apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention is the material, shape, structure, and arrangement of components. Etc. are not specified below. The technical idea of the present invention can be variously modified within the technical scope defined by the claims described in the claims.

Then, in the slot SL of the stator 22S, the first three-phase motor winding L1 and the second three-phase motor winding L1 which are the same phase with respect to the rotor magnet in the two systems shown in FIG. Two three-phase motor windings L2 are wound. The first three-phase motor winding L1 is star-connected by connecting one end of each of U-phase coils U1a and U1b , V-phase coils V1a and V1b, and W-phase coils W1a and W1b . Further, U-phase coil U1a, U1b, V-phase coil V1a, V1b and W-phase coils W1a, connected individually motor drive current I1u each other end motor controller 25 W1b, is I1v and I1w are supplied .

Further, the second three-phase motor winding L2 is star-connected by connecting one end of each of U-phase coils U2a and U2b , V-phase coils V2a and V2b, and W-phase coils W2a and W2b . Furthermore, the other ends of the U- phase coils U2a, U2b , the V-phase coils V2a, V2b and the W-phase coils W2a, W2b are connected to the motor control device 25, and motor drive currents I2u, I2v, and I2w are individually supplied .

Then, the phase coil portions U1a, U1b, V1a, V1b and W1a, W1b of the first three-phase motor winding L1, and the phase coil portions U2a, U2b, V2a, V2b of the second three-phase motor winding L2 and W2a and W2b are wound around slots SL sandwiching the teeth Te so that the directions of the energization currents are the same.
Thus, the phase coil portions U1a, U1b, V1a, V1b and W1a, W1b of the first three-phase motor winding L1, and the phase coil portions U2a, U2b, V2a, of the second three-phase motor winding L2 , V2b and W2a, and W2b, but are wound in different twelve teeth Te1~Te12 each other. That is, the twelve teeth Te 1～Te12, phase coils U1a whose forward upon one system, wound U 1 b, V1a, V1b and W1a, in order to W1b counterclockwise in the same winding direction, then the phase coils U2a that the two systems, U2b, V2a, V2b and W2a, are wound in sequence the W2b counterclockwise in the same winding direction. Further, the phase coils U1a to be the first system, U 1 b, V1a, V1b and W1a, wound in sequentially W1b counterclockwise in the same winding direction, finally, the phase coils U2a as a second system, U2b, V2a, V2b and W2a, are wound in sequence the W2b counterclockwise in the same winding direction. For this reason, the in-phase coil portions of the first three-phase motor winding L1 and the second three-phase motor winding L2 are simultaneously linked to the same magnetic flux formed by the permanent magnet PM of each magnetic pole of the rotor 22R. It is wound so that there is no. Therefore, each coil part of the first three-phase motor winding L1 and each coil part of the second three-phase motor winding L2 constitute a magnetic circuit that minimizes mutual magnetic interference. .

The field effect transistors QA1 to QA3 and QB1 to QB3 of the first and second motor current cut-off circuits 33A and 33B have the cathodes of the respective parasitic diodes D as the first and second inverter circuits 42A and 42B, respectively. Connected in the same direction.
Each of the first and second power cutoff circuits 44A and 44B has a series circuit configuration in which two field effect transistors (FETs) QC1, QC2 and QD1, QD2 connect the drains and the parasitic diodes are reversed. Have Then, connected to the output side of the noise filter 43 the source of the field effect transistors QC1 and QD1 is connected to each other, each of the field effect of the source of the field effect transistors QC2 and QD2 the first and second inverter circuits 42 A and 42B Connected to the sources of transistors Q1, Q2 and Q3.

The resolver abnormality diagnosis unit 61 detects an abnormality of the resolver 23a and outputs an abnormality detection signal SAr.
Further, although not shown in FIG. 5, the sub-motor electrical angle detection circuit 23c outputs the output shaft rotation angle detection value θos output from the output side rotation angle sensor 13c, the steering torque T, and the IGN switch 28. An ignition signal IGN indicating ON / OFF of the ignition is input. In addition, the first motor electrical angle θm1 from the angle calculation unit 60 and the abnormality detection signal SAr from the resolver abnormality diagnosis unit 61 are input.

The sub motor electrical angle detection circuit 23 c includes a relative offset amount estimation unit 62 and a motor electrical angle estimation unit 63.
The relative offset amount estimation unit 62 calculates the relative offset amount θoff between the origin θmd of the motor electrical angle θm (hereinafter sometimes referred to as “motor electrical angle origin θmd”) and the reference value θosr of the output shaft rotation angle detected value θos. Is estimated. Then, the estimated relative offset amount θoff is output to the motor electrical angle estimation unit 63.
The motor electrical angle estimator 63 detects the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c, the reduction ratio RGr of the reduction gear 21 stored in advance in the ROM 51, and the rotor 22R of the three-phase electric motor 22. Based on the number P of pole pairs and the relative offset amount θoff estimated by the relative offset amount estimation unit 62, the motor electrical angle estimated value θme is calculated. Then, the calculated motor electrical angle estimated value θme is output to the electrical angle selector 23d as the second motor electrical angle θm2.

Here, when the resolver 23a and the angle calculation unit 60 are normal, the origin θmd of the motor electrical angle is known, so that it is possible to easily estimate the relative offset amount with respect to the reference value θosr of the output shaft rotation angle detection value. .
The reference value θosr is obtained by multiplying the detected value of the output shaft rotation angle when the system is started (when the IGN switch 28 is turned from OFF) by the pole pair number P and the reduction ratio RGr .
In order to supplement the motor electrical angle θm with the output shaft rotation angle detection value θos , the number of pole pairs P, and the reduction ratio RGr , the motor electrical angle origin θmd (0 degree) and the reference value θosr of the output shaft rotation angle detection value are set. Must match. For example, as shown in FIG. 10, when the reference value θosr and the motor electrical angle origin θmd do not coincide with each other, the motor electrical angle θm indicated by the solid line in FIG. On the other hand , an angle error occurs in the output shaft rotation angle θos , the number of pole pairs P, and the reduction ratio RGr (displacement from the reference value θosr) . Therefore, results in a large deviation occurs for motor electric angle θm of the actual.

Therefore, how much the reference value θosr of the output shaft rotation angle detection value is deviated from the motor electrical angle origin θmd is obtained as a relative offset amount, and the relative offset amount is added when estimating the motor electrical angle (relative It is necessary to correct with the offset amount).
The second relative offset amount estimation unit 71 receives the abnormality detection signal SAr in the initial diagnosis by the resolver abnormality diagnosis unit 61 when the system is restarted after the system stop when the ignition switch is turned off and the IGN switch 28 is turned on again. When the value indicates that there is an abnormality, the second relative offset amount θoff2 is estimated. Then, the estimated second relative offset amount θoff2 is stored in the RAM 50.

(Effect of embodiment)
(1) In the motor control device 25 according to the present embodiment, the relative offset amount estimation unit 62 detects the output shaft detected by the output-side rotation angle sensor 13c that detects the steering angle of the steering (output shaft rotation angle detection value θos). A relative offset amount θoff between the reference value θosr of the rotation angle detection value and the motor electrical angle origin θmd of the three-phase electric motor 22 that generates the steering assist force is estimated. The motor electrical angle estimator 63 estimates the motor electrical angle θm based on the detected output shaft rotation angle value θos and the relative offset amount θoff. The control arithmetic unit 31 and the motor electrical angle detection circuit 23 drive-control the three-phase electric motor 22 based on the first motor electrical angle θm1 detected by the resolver 23a and the angle calculation unit 60 when they are normal. On the other hand, when the resolver 23a and the angle calculation unit 60 are abnormal, the three-phase electric motor 22 is driven and controlled based on the second motor electrical angle θm2 estimated by the motor electrical angle estimation unit 63.

With this configuration, the relative offset amount θoff between the reference value θosr of the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c and the motor electrical angle origin θmd of the three-phase electric motor 22 is estimated, and output The motor electrical angle θm can be estimated based on the detected shaft rotation angle value θos and the relative offset amount θoff. When at least one of the resolver 23a and the angle calculation unit 60 is abnormal, it is possible to drive and control the three-phase electric motor 22 based on the estimated motor electrical angle θm2.
As a result, even when at least one of the resolver 23a and the angle calculation unit 60 is abnormal, the three-phase electric motor 22 can be continuously driven.

(2) In the motor control device 25 according to the present embodiment, the torque sensor 13 detects the steering torque T transmitted to the steering mechanism. The output side rotation angle sensor 13c detects the steering angle of the steering (output shaft rotation angle detection value θos). A three-phase electric motor 22 generates a steering assist force. The resolver 23 a and the angle calculation unit 60 detect the motor electrical angle θm of the three-phase electric motor 22. The first and second inverter circuits 42 </ b> A and 42 </ b> B supply drive current to the three-phase electric motor 22. The control arithmetic device 31 drives and controls the first and second inverter circuits 42A and 42B based on the steering torque T detected by the torque sensor 13 and the motor electrical angle θm detected by the resolver 23a and the angle calculator 60. The resolver abnormality diagnosis unit 61 diagnoses abnormality of the resolver 23a and the angle calculation unit 60. The relative offset amount estimation unit 62 estimates the relative offset amount θoff between the output shaft rotation angle detection value reference value θosr and the motor electrical angle origin θmd. The motor electrical angle estimation unit 63 estimates the motor electrical angle θm based on the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c and the relative offset amount θoff estimated by the relative offset amount estimation unit 62. When the resolver abnormality diagnosis unit 61 diagnoses that at least one of the resolver 23 a and the angle calculation unit 60 is abnormal, the control arithmetic unit 31 estimates the steering torque T detected by the torque sensor 13 and the motor electrical angle estimation unit 63. The first and second inverter circuits 42A and 42B are driven and controlled based on the two motor electrical angles θm2.

With this configuration, the relative offset amount θoff between the reference value θosr of the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c and the motor electrical angle origin θmd of the three-phase electric motor 22 is estimated, and output The motor electrical angle θm can be estimated based on the detected shaft rotation angle value θos and the relative offset amount θoff. When at least one of the resolver 23a and the angle calculator 60 is abnormal, it is possible to drive and control the multiphase electric motor based on the estimated motor electrical angle θm2.
As a result, even when at least one of the resolver 23a and the angle calculation unit 60 is abnormal, the three-phase electric motor 22 can be continuously driven.

(3) In the motor control device 25 according to the present embodiment, the relative offset amount estimation unit 62 detects the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c when the resolver 23a and the angle calculation unit 60 are normal. The first relative offset amount θoff1 is estimated based on the motor electrical angle θm detected by the resolver 23a and the angle calculator 60, and the estimated first relative offset amount θoff1 is stored in the RAM 50. When the motor electrical angle estimator 63 detects that at least one of the resolver 23a and the angle calculator 60 is abnormal by the resolver abnormality diagnosis unit 61 during system startup, the output shaft rotation angle detected by the output side rotation angle sensor 13c is detected. The motor electrical angle θm is estimated based on the value θos and the first relative offset amount θoff1 stored in the RAM 50.

With this configuration, when the resolver 23a and the angle calculation unit 60 are normal, the output shaft rotation angle detection value θos detected by the output side rotation angle sensor 13c and the motor electrical angle θm detected by the resolver 23a and the angle calculation unit 60. Based on the above, the first relative offset amount θoff1 can be estimated and stored in the RAM 50.
As a result, even if an abnormality occurs in at least one of the resolver 23a and the angle calculation unit 60 during system startup, it is possible to estimate an accurate motor electrical angle from the first relative offset amount θoff1 stored in the RAM 50. .
This makes it possible to continue to drive the three-phase electric motor 22 even when at least one of the resolver 23a and the angle calculation unit 60 is abnormal during system startup.

(4) In the motor control device 25 according to the present embodiment, the relative offset amount estimation unit 62 is diagnosed as abnormal in at least one of the resolver 23a and the angle calculation unit 60 by the initial diagnosis by the resolver abnormality diagnosis unit 61 at the time of system startup. Then, a motor driving current (eg, a step-wave motor driving current) that vibrates positively and negatively is passed through the three-phase electric motor 22 via the control arithmetic unit 31 and the first and second inverter circuits 42A and 42B. The motor electrical angle origin θmd is estimated based on the amplitude of the steering torque T detected by the torque sensor 13 when the drive current is passed, and the second relative offset amount θoff2 is estimated based on the estimated motor electrical angle origin θmd. When the motor electrical angle estimator 63 diagnoses that at least one of the resolver 23a and the angle calculator 60 is abnormal in the initial diagnosis by the resolver abnormality diagnosis unit 61, the output shaft rotation angle detection value detected by the output side rotation angle sensor 13c. The motor electrical angle θm is estimated based on θos and the second relative offset amount θoff2.

(Modification)
(1) In the above embodiment, the motor electrical angle is estimated based on the output shaft rotation angle detection value θos detected by the output-side rotation angle sensor 13c constituting the torque sensor 13, but the present invention is not limited to this configuration. For example, other sensors can be used as long as they detect the rotation angle of the shaft that rotates in accordance with the operation of the steering wheel 11, such as estimating the motor electrical angle based on the input shaft rotation angle θis detected by the input side rotation angle sensor 13b. The motor electrical angle may be estimated on the basis of the rotation angle detected in (1).
(2) In the above embodiment, in the steering assist control process of the control arithmetic unit 31, the d-axis current command value Id ^* and the q-axis current command value Iq ^* are calculated based on the steering assist current command value, and these are calculated as dq. Phase-to-phase conversion is performed to calculate a U-phase current command value Iu ^* , a V-phase current command value Iv ^*, and a W-phase current command value Iw ^* , and a current deviation ΔIu between these and an added value for each phase of the current detection value , ΔIv and ΔIw have been described. However, the present invention is not limited to the above configuration, and the addition value for each phase of the current detection value is converted to dq axis, and the deviation between these values and the d axis current command value Id ^* and q axis current command value Iq ^*. ΔId and ΔIq may be calculated, and the deviations ΔId and ΔIq may be dq-phase to three-phase converted.
(3) In the above embodiment, an example in which the present invention is applied to a column assist type electric power steering apparatus has been described. However, the present invention is not limited to this configuration. For example, the present invention is applied to a rack assist type or pinion assist type electric power steering apparatus. It is good also as composition to apply.

Claims (1)

Offset amount estimation for estimating a relative offset amount between the reference value of the steering angle detected by the steering angle detection unit that detects the steering angle of the steering and the origin of the motor electrical angle of the multiphase electric motor that generates the steering assist force And
A motor electrical angle estimation unit that estimates the motor electrical angle based on the steering angle detected by the steering angle detection unit and the relative offset amount estimated by the offset amount estimation unit;
When the motor electrical angle detection unit for detecting the motor electrical angle is normal, the multiphase electric motor is driven and controlled based on the motor electrical angle detected by the motor electrical angle detection unit, and when the motor electrical angle detection unit is abnormal And a motor drive control unit configured to drive and control the multiphase electric motor based on the estimated motor electrical angle estimated by the motor electrical angle estimation unit.

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