JP2017192203A - Motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor controller capable of shortening the time required for positioning of a rotor more than before.SOLUTION: A motor 20 includes three-phase stator windings X, Y, Z for detection, separately from three-phase stator windings U, V, W for driving. A controller 10 electrifies a predetermined stator winding for driving, for positioning. Position of a rotor 22 subjected to positioning is estimated, when the rotor 22 is rotated by this electrification, based on the combination of polarities of induction voltages induced in the three-phase stator windings X, Y, Z for detection. As a result, the rotor 22 can be positioned by performing electrification once, and the time required for positioning of the rotor 22 can be shortened more than before.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor control device capable of quickly positioning a rotor of a motor.

  For example, in the drive control device for a three-phase DC motor described in Patent Document 1, when a three-phase DC motor is energized in two phases, a result of comparing an induced voltage generated in a phase winding that is de-energized with a reference voltage Is used to estimate the angular range in which the magnetic pole position of the rotor exists. Then, based on the estimated angle range, the rotor positioning angle is determined, and the rotor is positioned by energizing the phase winding according to the determined positioning angle.

  The rotor positioning angle is determined to be less than a half rotation with respect to the magnetic pole position of the rotor in the stopped state. In this way, the time until the motor is started is reduced by suppressing the angular displacement of the rotor from the initial position in the stopped state to the positioning position before the start.

JP 2011-36083 A

  However, in the above-described apparatus of Patent Document 1, it is necessary to energize the phase windings for estimating the angle range in which the magnetic pole position of the rotor exists and energize the total windings for positioning the rotor. is there. As described above, in the apparatus of Patent Document 1, since it is necessary to energize twice for positioning the rotor, there is a limit to shortening the time required for positioning the rotor.

  The present invention has been made in view of the above-described points, and an object of the present invention is to provide a motor control device capable of shortening the time required for positioning of the rotor as compared with the prior art.

In order to achieve the above object, a motor control device according to a first invention comprises:
In order to position the rotor (22) of the motor (20), positioning energization is performed to energize a predetermined driving stator winding among the three-phase driving stator windings (U, V, W) of the motor. Part (S300),
The rotor is rotated by energization by the positioning energization unit, and the magnetic flux acting from the rotor is changed, so that the three-phase detection stator windings (X, Y, A position estimation unit (S330) for estimating a position where the rotor is positioned based on a combination of polarities of induced voltages induced in Z);
In order to rotate the rotor from the stopped state, the rotating magnetic field is switched by switching the three-phase driving stator winding to be energized in accordance with the change in the induced voltage induced in the three-phase detecting stator winding. And a starting unit (S120) for changing the driving stator winding for starting energization according to the position of the rotor estimated by the position estimating unit.

  Thus, in the motor control device according to the first aspect of the present invention, the motor includes the three-phase detection stator windings in addition to the three-phase driving stator windings, and the position estimation unit performs positioning energization. The rotor is positioned based on the combination of the polarity of the induced voltages induced in the three-phase detection stator winding when the rotor is rotated by energizing the predetermined driving stator winding by the unit. Estimate the position. That is, in the motor control device according to the first aspect of the present invention, when the rotor is rotated by energizing a predetermined driving stator winding by the positioning energization unit, the induced voltage generated by the rotation of the rotor is detected in three phases. It is possible to measure with the stator winding. Therefore, based on the combination of induced voltages measured by these three-phase detection stator windings, the rotor magnetic pole position is estimated in a more specific narrow range rather than a wide angular range as in the past. can do. As a result, the rotor can be positioned only once, and the time required for positioning the rotor can be shortened as compared with the prior art.

The motor control device according to the second invention is
In order to position the rotor (22) of the motor (20), positioning energization is performed to energize a predetermined driving stator winding among the three-phase driving stator windings (U, V, W) of the motor. Part (S300),
A rotation direction detection unit (S315) that detects a rotation direction of the rotor when the rotor is rotated by energization by the positioning energization unit;
The rotor is rotated by energization by the positioning energization unit, and the magnetic flux acting from the rotor is changed, so that it is induced in the one-phase detection stator winding (X) different from the three-phase driving stator winding. A position estimation unit (S335) for estimating the position of the rotor based on the polarity of the induced voltage and the rotation direction of the rotor detected by the rotation direction detection unit;
In order to rotate the rotor from the stopped state, the rotating magnetic field is switched by switching the three-phase driving stator winding to be energized in accordance with the change in the induced voltage induced in the three-phase detecting stator winding. And a starting unit (S120) for changing the driving stator winding for starting energization according to the position of the rotor estimated by the position estimating unit.

  As described above, the motor control device according to the second aspect of the present invention includes the rotation direction detection unit that detects the rotation direction of the rotor, and the position estimation unit rotates by energizing a predetermined driving stator winding by the positioning energization unit. When the rotor rotates, the position of the rotor is determined based on the polarity of the induced voltage induced in the one-phase detection stator winding and the rotation direction of the rotor detected by the rotation direction detector. presume. In addition to the polarity of the induced voltage measured by the one-phase detection stator winding, if information on the rotation direction of the rotor can be obtained, the induced voltage measured by the three-phase detection stator winding The magnetic pole position of the rotor can be estimated with a narrow range and accuracy equivalent to the combination. Therefore, even with the motor control device according to the second aspect of the invention, the rotor can be positioned with a single energization, and the time required for the positioning of the rotor can be shortened as compared with the prior art.

  The reference numerals in the parentheses merely show an example of a correspondence relationship with a specific configuration in an embodiment described later in order to facilitate understanding of the present invention, and are intended to limit the scope of the present invention. Not intended.

  Further, the technical features described in the claims of the claims other than the features described above will become apparent from the description of embodiments and the accompanying drawings described later.

It is a block diagram which shows schematic structure of the whole control system containing the motor control apparatus which concerns on 1st Embodiment. It is a flowchart which shows the process performed when the ignition switch of a vehicle is turned ON and the power supply to a control apparatus is started. It is a flowchart which shows the detailed process of the positioning control in the flowchart of FIG. It is a flowchart which shows the detailed process of the sensorless start in the flowchart of FIG. It is a flowchart which shows the detailed process of the offset error correction value learning in the flowchart of FIG. It is explanatory drawing for demonstrating positioning control. It is a figure which shows the position where the rotor of a motor stops by positioning control. It is a figure which shows the relationship between the polarity of the induced voltage of a stator winding for three phases, and the stop position of a rotor. It is a figure which shows the relationship between the polarity of the induced voltage of the stator winding of 1 phase detection, the rotation direction of a rotor, and the stop position of a rotor. It is a flowchart which shows the detailed process of the positioning control in 2nd Embodiment.

(First embodiment)
Hereinafter, the motor control device according to the first embodiment of the present invention will be described in detail with reference to the drawings. In the present embodiment, an example will be described in which the motor is connected to a vehicle engine via a belt or the like, and used as an integrated starter generator (ISG) that starts the engine, assists engine torque, and generates electric power.

  FIG. 1 is a configuration diagram showing a schematic configuration of the entire control system including the motor control device 10 according to the first embodiment. As shown in FIG. 1, the control system includes a motor control device 10, a motor 20, and an angle sensor 30 as main components.

  In the motor 20, a stator 21 is provided with six-phase (U-phase, V-phase, W-phase, X-phase, Y-phase, Z-phase) stator windings. The U-phase, V-phase, and W-phase stator windings are respectively installed at positions shifted by 120 ° in electrical angle. Similarly, the X-phase, Y-phase, and Z-phase stator windings are also installed at positions shifted by 120 ° in electrical angle. In the present embodiment, the stator windings of the respective phases are arranged so that the U phase and the X phase, the V phase and the Y phase, and the W phase and the Z phase are shifted from each other by 30 ° in electrical angle. The stator 21 is provided. Therefore, the U-phase, V-phase, and W-phase three-phase stator windings and the X-phase, Y-phase, and Z-phase stator windings alternate along the rotation direction of the rotor 22. Is provided. However, the deviation angle is not limited to 30 °. For example, the U phase and the X phase, the V phase and the Y phase, and the W phase and the Z phase may be provided so as to be shifted from each other by 60 ° in electrical angle.

  The motor 20 includes a rotor 22 having a permanent magnet. FIG. 1 shows an example in which one S-pole and one N-pole permanent magnet is provided. However, a plurality of S-pole and N-pole permanent magnets may be provided. The rotor 22 may be composed of a permanent magnet itself, or may be embedded in the rotor 22 or may be attached to the outer surface. Further, the rotor 22 may be configured to generate a magnetic force by an electromagnet instead of a permanent magnet.

  The direction of the magnetic force generated by the rotor 22 changes as the rotor 22 rotates. As a result, since the number of interlinkage magnetic fluxes of each stator winding changes, when the rotor 22 rotates, a voltage corresponding to the change in the number of interlinkage magnetic fluxes is induced in each stator winding.

  A detection magnet 31 is provided on the shaft serving as the rotation axis of the rotor 22 in order to detect the rotation angle of the rotor 22 (for example, the rotation angle position of the center of the south pole). Further, a detection element (for example, a Hall element) 32 for detecting the rotation angle of the detection magnet 31 is provided in the vicinity of the detection magnet 31. The detection magnet 31 and the detection element 32 constitute an angle sensor 30 that detects the rotation angle of the rotor 22.

  The detection element 32 is not limited to a Hall element, and for example, a magnetoresistive element may be used. Further, as the angle sensor 30, a sensor other than the magnetic sensor, for example, a photo interrupter type optical sensor may be used.

  When the detection magnet 31 is installed and fixed on the shaft, it is a laborious and time-consuming operation to perfectly match the actual rotation angle of the rotor 22 and the rotation angle detected by the angle sensor 30. Therefore, in the present embodiment, as shown in FIG. 1, the actual rotation angle of the rotor 22 and the rotation angle detected by the angle sensor 30 are allowed to deviate. In the manufacturing stage, the deviation between the actual rotation angle of the rotor 22 and the rotation angle detected by the angle sensor 30 is determined as an offset error based on the induced voltage induced in the stator winding and the detection signal from the angle sensor 30. measure. Further, an offset error correction value for making the offset error zero is stored in advance in a writable nonvolatile memory 11 in the control device 10. When detecting the rotation angle of the rotor 22 based on the sensor detection signal of the angle sensor 30, the control device 10 corrects the rotation angle calculated based on the sensor detection signal with the stored correction value. Thus, the correct rotation angle of the rotor 22 is detected.

  The control device 10 includes an inverter circuit that supplies current to each stator winding of the motor 20. The inverter circuit includes a first inverter circuit that controls energization of the three-phase stator windings of U phase, V phase, and W phase, and three-phase stator windings of X phase, Y phase, and Z phase. A second inverter circuit for controlling energization. Each of the first inverter circuit and the second inverter circuit includes, for example, six MOSFETs or IGBTs each having a reflux diode connected in parallel as a switching element. These switching elements are connected to the upper arm and the lower arm for each phase, and the midpoint between the upper arm and the lower arm is connected to the stator winding of each phase. Therefore, by changing the combination of the switching element on the upper arm side to be turned on and the switching element on the lower arm side to be turned on, a current can be supplied to a desired stator winding in a desired direction. Moreover, when the motor 20 generates electric power, it is possible to recover electric power from a desired stator winding to the in-vehicle battery.

  Thus, the motor 20 in this embodiment has a U-phase, V-phase, and W-phase three-phase stator winding, and an X-phase, Y-phase, and Z-phase three-phase stator winding. And a first inverter circuit and a second inverter circuit for controlling energization to the respective three-phase stator windings. Thereby, the control apparatus 10 can drive the motor 20 as a 6-phase motor or a 3-phase double motor.

  The control device 10 has a control circuit for controlling on / off of each switching element of the first inverter circuit and the second inverter circuit. This control circuit starts the motor 20 sensorlessly without using the sensor detection signal from the angle sensor 30 when the ignition switch of the vehicle is turned on and the motor 20 is started for the first time.

  In the writable nonvolatile memory 11, for example, there is a possibility that stored data may be lost or altered due to the influence of noise or the like. If the offset error correction value stored in the non-volatile memory 11 is lost or altered, there is a possibility that the motor 20 cannot be appropriately controlled when the stored correction value is used. Therefore, in this embodiment, when the motor 20 is started for the first time, the motor 20 is sensorlessly started. In the sensorless start, when it is determined that the correction value is appropriate or an appropriate correction value is calculated, the control shifts to drive control of the motor 20 using the sensor detection signal from the angle sensor 30.

  In preparation for sensorless start-up of the motor 20, the control device 10 first sets a predetermined stator winding (of the three-phase stator windings of U phase, V phase, and W phase) via the first inverter circuit ( For example, the rotor 22 is positioned by rotating the rotor 22 by energizing from the U phase to the V phase. Next, in the position of the positioned rotor 22, the U-phase, V-phase, and W-phase stator windings are arranged so that the maximum rotational torque can be applied to the rotor 22. Thus, the stator winding to be energized and the energization direction are determined, and energization for sensorless start is started. As described above, in the positioning of the rotor 22 and the sensorless start, the three-phase stator windings of the U phase, the V phase, and the W phase are used as driving stator windings for driving the motor 20.

  During positioning of the rotor 22 and sensorless start-up, the control circuit of the control device 10 is configured not to energize the three-phase stator windings of the X phase, the Y phase, and the Z phase. When the rotor 22 is positioned, as the rotor 22 rotates, a voltage corresponding to a change in the rotation angle of the rotor 22 is induced in the three-phase stator windings of the X phase, the Y phase, and the Z phase. The The control device 10 takes in the induced voltages of these X-phase, Y-phase, and Z-phase stator windings, and compares each phase of the X-phase, Y-phase, and Z-phase with a virtual neutral point potential that is a reference voltage. The polarity of the induced voltage is determined. Further, the control device 10 estimates the rotation angle of the rotor 22 from the combination of the polarities of the induced voltages of the determined X-phase, Y-phase, and Z-phase. In addition, in the case of sensorless start, the control device 10 determines whether the energized U phase, V phase, and the like according to changes in the induced voltage induced in the three-phase stator windings of the X phase, the Y phase, and the Z phase. A rotating magnetic field is generated by switching the W-phase three-phase stator winding. As described above, in the positioning of the rotor 22 and the sensorless start, the three-phase stator windings of the X phase, the Y phase, and the Z phase detect the induced voltage corresponding to the rotation angle of the rotor 22 of the motor 20. Used as a detection stator winding.

  Here, in the conventional sensorless drive, when the induced voltage of one phase, which is not energized among the three-phase stator windings, crosses the neutral point potential (when zero crossing), the rotation angle of the rotor is changed. The two phases to be energized are estimated and switched. However, in such a conventional sensorless drive, the non-energization period of each phase is limited. Therefore, for example, when the rotational speed of the motor changes suddenly due to a sudden load fluctuation, it may not be possible to detect that zero crossing has occurred. There is. For example, when the motor 20 is used as an integrated starter generator as in this embodiment, a load such as a compressor or an oil pump of an air conditioner can change the rotational speed of the engine (that is, the rotational speed of the motor 20). There is sex.

  Furthermore, in the case of the conventional sensorless drive, a self-induced electromotive force is generated in the stator winding immediately after being switched to non-energization, and the self-induced electromotive force is superimposed on the induced voltage due to the rotation of the rotor. For this reason, there is a possibility that the point where the induced voltage due to the rotation of the rotor is zero-crossed cannot be accurately measured due to the influence of the self-induced electromotive force.

  In this regard, in the present embodiment, the control device 10 is provided with a three-phase detection stator winding of X phase, Y phase, and Z phase during positioning of the rotor 22 and sensorless start. Since energization is not performed, a change in polarity of the induced voltage due to rotation of the rotor 22 can be correctly measured. Further, the control device 10 estimates the positioned position of the rotor 22 based on the combination of the polarities of the induced voltages induced in the three-phase detection stator windings. For this reason, the position where the rotor 22 is positioned can be narrowed down and estimated. Therefore, the positioning of the rotor 22 can be performed with one energization, and the time required for the positioning of the rotor 22 can be shortened as compared with the prior art. As a result, the sensorless start of the motor 20 can be started early. And the timing which performs the determination whether the offset error correction value is appropriate, etc. performed when the rotor 22 reaches a predetermined rotational speed by the sensorless start can be advanced. Therefore, it is possible to shorten the time required for shifting to drive control of the motor 20 using the sensor detection signal from the angle sensor 30.

  Hereinafter, the detailed content of the process performed in the control apparatus 10 is demonstrated using the flowchart of FIGS.

  The process shown in the flowchart of FIG. 2 is executed when the ignition switch of the vehicle is turned on and the power supply to the control device 10 is started. In the first step S100, it is determined whether or not an engine start is requested by operating the ignition switch to the engine start position. When the engine start is requested, the process proceeds to step S110. On the other hand, if the ignition switch is at the accessory position or the like, it is determined that the engine start is not requested, and the process proceeds to step S160.

  In step S110, as a preparation for starting the engine by sensorless start of the motor 20, first, positioning control of the rotor 22 of the motor 20 is executed. The detailed processing of this positioning control is shown in the flowchart of FIG. Hereinafter, the positioning control will be described with reference to the flowchart of FIG.

  In step S300 of the flowchart of FIG. 3, the rotor 22 is rotated by energizing a predetermined stator winding among the three-phase driving stator windings of the U phase, the V phase, and the W phase. For example, when a predetermined stator winding is energized from the U phase to the V phase, the U phase becomes the S pole and the V phase becomes the N pole. In this case, the direction of the magnetic field by the U-phase and V-phase stator windings is the direction toward the X-phase stator windings, as indicated by the dotted arrows in FIG.

  At this time, the rotor 22 rotates to a position shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C according to the initial stop position and stops. FIG. 7A shows a position A where the magnetic field direction of the stator winding indicated by the dotted line arrow and the magnetic field direction of the rotor 22 indicated by the one-dot chain line arrow are orthogonal to each other as the stationary position. More specifically, in the position A shown in FIG. 7A, the magnetic field direction of the rotor 22 is delayed by 90 ° in electrical angle from the magnetic field direction of the stator winding in the clockwise direction as the first rotation direction. Position. FIG. 7B shows a rotor position B as a stationary position in which the magnetic field direction of the rotor 22 is opposite to that in FIG. 7A, but orthogonal to the magnetic field direction of the stator winding. Has been. The position B shown in FIG. 7B is a position where the magnetic field direction of the rotor 22 is advanced 90 ° in electrical direction from the magnetic field direction of the stator winding in the clockwise direction as the first rotation direction. . FIG. 7C shows a position C where the magnetic field direction of the stator winding and the magnetic field direction of the rotor 22 face each other as a stationary position.

  Here, the reason why the rotor 22 stops at the position A and the position B will be described. For example, when the magnitude of the magnetic field generated by energizing the driving stator winding is relatively small and the rotational torque for rotating the rotor 22 is small, the center positions of the S pole and N pole of the rotor 22 are In each case, when the magnetic field of the driving stator winding is in the middle position between the S pole and the N pole, the attractive force and the repulsive force of both magnetic fields become small, and the rotor 22 cannot be rotated any more. is there. This is the reason why the rotor 22 is stationary at the position A or the position B.

  Originally, in the positioning control, the rotor 22 should be prevented from standing still at such unscheduled positions A and B. However, in this embodiment, since the induced voltage due to the rotation of the rotor 22 can be measured with the three-phase detection stator windings of the X phase, the Y phase, and the Z phase, the rotor 22 is positioned at the position A or It can be estimated that the camera is stationary at the position B. Therefore, in this embodiment, the position A and the position B are positively used as the stationary position of the rotor 22 by adjusting the magnitude of the magnetic field generated by the driving stator winding during positioning. did. By using such position A and position B as the stationary position of the rotor 22, the angular displacement of the rotor 22 during positioning can be suppressed to 90 ° or less.

  Specifically, when the initial stop position (the center position of the S pole) of the rotor 22 belongs to the angle ranges 1 to 3 in FIG. In response, the rotor 22 rotates clockwise. However, in this case, the rotor 22 stops at the rotation angle position of the rotor 22 in the vicinity of the position B shown in FIG. The polarities of the induced voltages of the three-phase detection stator windings measured before the rotor 22 is stationary are positive for the X phase, positive for the Y phase, and negative for the Z phase. When the initial stop position of the rotor 22 belongs to the angle range 1, the initial polarity of the Y phase is negative, but when the rotor 22 rotates and enters the area of the angle range 2, the polarity of the Y phase is Invert to plus. Therefore, as shown in FIG. 8, when the induced voltage of the combination of the X phase plus, the Y phase plus, and the Z phase minus is measured by the three-phase detection stator winding immediately before the rotor 22 stops. It can be estimated that the rotor 22 is stationary at the position B. And since the rotor 22 only rotates from the initial position which belongs to the angle ranges 1-3 to the position B, the angular displacement of the rotor 22 is suppressed to 90 degrees or less.

  In addition, when the initial stop position of the rotor 22 belongs to the angle range 4 to 6 in FIG. 6, the rotor 22 is rotated clockwise by receiving the repulsive force and the attractive force due to the magnetic field by the stator winding indicated by the dotted arrow. Rotate. On the other hand, when the initial stop position of the rotor 22 belongs to the angle ranges 7 to 9 in FIG. 6, the rotor 22 is counterclockwise by receiving the repulsive force and the attractive force due to the magnetic field by the stator winding indicated by the dotted arrows. Rotate to. In any case, the attracting force between the magnetic field of the stator winding and the magnetic field of the rotor 22 becomes the largest when the rotational angle position of the rotor 22 is in the vicinity of the position C shown in FIG. The rotor 22 is stationary. The polarity of the induced voltage of the three-phase detection stator winding, which was measured before the rotor 22 stopped, is negative for the X phase and the initial position for the Y phase is in the angle range 4-7. Is positive if the initial position belongs to the angular range 8-9, minus for the Z phase if the initial position belongs to the angular range 4-5, positive if the initial position belongs to the angular range 6-9. Become. Therefore, in this case, as shown in FIG. 8, the polarity of the induced voltage measured by the X-phase stator winding is negative regardless of the polarity of the Y-phase and Z-phase induced voltages. It can be estimated that the child 22 is stationary at the position C. Even when the rotor 22 is stationary at the position C, the displacement angle of the rotor 22 is suppressed to 90 ° or less.

  Furthermore, when the initial stop position of the rotor 22 belongs to the angle range 10 to 12 in FIG. 6, the rotor 22 is counterclockwise by receiving a repulsive force and an attractive force due to the magnetic field by the stator winding indicated by the dotted arrow. Rotate to. However, in this case, the rotor 22 stops at a rotation angle position of the rotor 22 in the vicinity of the position A shown in FIG. The polarities of the induced voltages of the three-phase detection stator windings measured before the rotor 22 is stationary are positive for the X phase, negative for the Y phase, and positive for the Z phase. When the initial stop position of the rotor 22 belongs to the angle range 12, the initial polarity of the Z phase is negative, but when the rotor 22 rotates and enters the region of the angle range 11, the polarity of the Z phase is Invert to plus. Therefore, as shown in FIG. 8, when the induced voltage of the combination of the X phase plus, the Y phase minus, and the Z phase plus is measured by the three-phase detection stator winding immediately before the rotor 22 stops. It can be estimated that the rotor 22 is stationary at the position A. And since the rotor 22 only rotates from the initial position which belongs to the angle ranges 10-12 to the position A, the angular displacement of the rotor 22 is suppressed to 90 degrees or less.

  Returning to the flowchart of FIG. 3 again, the description will be continued. In step S310 executed after step S300 described above, the polarity of the induced voltage measured by the three-phase detection stator winding is detected. In a succeeding step S320, it is determined whether or not the rotation of the rotor 22 is stopped. Whether or not the rotation of the rotor 22 has stopped can be determined based on, for example, that the induced voltage measured by the detection stator winding has become substantially zero. Alternatively, the determination may be made based on whether or not a predetermined time set based on the time required for the rotor 22 to rotate 90 ° has elapsed since the start of energization of the driving stator winding.

  If it is determined in step S320 that the rotation of the rotor 22 has stopped, the process proceeds to step S330. On the other hand, when it determines with rotation of the rotor 22 not stopping, it returns to the process of step S300. In step S330, the position where the rotor 22 is positioned is estimated based on the combination of the polarities of the induced voltages of the three-phase detection stator windings detected immediately before the rotor 22 stops. This completes the positioning control.

  After the end of the positioning control, sensorless start is performed in step S120 of the flowchart of FIG. The detailed processing of this sensorless start is shown in the flowchart of FIG. Hereinafter, the sensorless start will be described with reference to the flowchart of FIG.

  In step S400 of the flowchart of FIG. 4, the U phase, the V phase, and the W phase are set so that the maximum rotational torque can be applied to the rotor 22 according to the estimated position of the rotor 22 positioned. Among the three-phase driving stator windings of the phase, the driving stator winding to be energized and the energizing direction are determined. In subsequent step S410, energization for the sensorless start is started by energizing the determined driving stator winding in the determined energization direction.

  In step S420, the polarity change of the induced voltage measured by the three-phase detection stator winding is detected. In the subsequent step S430, it is determined whether or not the rotation angle of the rotor 22 calculated based on the detected change in the induced voltage is a rotation angle at which energization to the driving stator winding should be switched. In this determination process, if it is determined that the rotation angle for energization switching has not yet been reached, the process returns to step S410. On the other hand, if it determines with having reached the rotation angle which should perform energization switching, it will progress to the process of step S440.

  In step S440, the driving stator winding to be energized after switching and its energization direction are determined. In step S450, the rotation angle of the rotor 22 is updated. In step S460, the rotation angle of the rotor 22 is determined based on the previous rotation angle of the rotor 22, the updated rotation angle of the rotor 22, and the elapsed time. Calculate the rotation speed.

  In step S470, it is determined whether or not the rotation speed of the rotor 22 calculated in step S460 has reached a learnable rotation speed. In the present embodiment, the rotation angle of the rotor 22 is calculated from the change in the induced voltage measured by the detection stator winding while rotating the rotor 22 of the motor 20 by sensorless start. At this time, as the rotation speed of the rotor 22 increases, the accuracy of the rotation angle of the rotor 22 calculated from the change in the induced voltage of the detection stator winding also increases. In the present embodiment, as described later, whether or not the offset error correction value stored in the nonvolatile memory 11 is normal using the rotation angle of the rotor 22 calculated from the change in the induced voltage. Determine. Furthermore, when it is determined that the offset error correction value is abnormal, the stored offset error correction value is updated with the offset error correction value calculated using the rotation angle of the rotor 22 calculated from the change in the induced voltage. To do. Therefore, in step S470, the rotor 22 has a high accuracy so that the rotation speed of the rotor 22 can determine whether the offset error correction value is normal and an appropriate offset error correction value can be calculated. It is determined whether or not the rotation speed at which the rotation angle of 22 can be calculated has been reached. If it is determined in step S470 that the rotation speed of the rotor 22 has not reached the learnable rotation speed, the process returns to step S410. On the other hand, if it is determined in step S470 that the rotational speed of the rotor 22 has reached the learnable rotational speed, the sensorless start shown in the flowchart of FIG. 4 is terminated.

  After completion of the sensorless start, offset error correction value learning is performed in step S130 of the flowchart of FIG. The detailed processing of this offset error correction value learning is shown in the flowchart of FIG. Hereinafter, the offset error correction value learning will be described with reference to the flowchart of FIG.

  In step S500 of the flowchart of FIG. 5, it is determined whether or not the engine that rotates together with the motor 20 starts autonomously by sensorless start of the motor (ISG) 20 and the start of the engine is completed. If it is determined that the engine has been started, the process proceeds to step S510. If it is determined that the engine has not been started, the process proceeds to step S520. In step S510, sensorless driving is continued. That is, the motor 20 is rotated by switching the driving stator winding to be energized based on the change in the induced voltage measured by the detection stator winding. On the other hand, in step S520, energization of the driving stator winding is terminated. In this case, the motor 20 is rotated by the rotation of the engine.

  In step S530, it is determined whether the polarity of the induced voltage measured by any of the detection stator windings has changed. If it is determined in step S530 that the polarity of the induced voltage has changed, the process proceeds to step S540. If it is determined that the polarity has not changed, the process returns to step S500. Since the rotation angle of the rotor 22 can be calculated with high accuracy when the polarity of the induced voltage measured by any one of the detection stator windings changes, in step S540, the measurement is performed using the three-phase stator windings. The rotation angle (first rotation angle) of the rotor 22 is calculated from the induced voltage.

  In the subsequent step S550, the rotation angle (second rotation angle) of the rotor 22 is calculated from the sensor detection signal of the angle sensor 30. In step S570, the difference between the first rotation angle and the second rotation angle is calculated as a learning offset error correction value.

  In the subsequent step S570, the stored offset error correction value (stored offset error correction value) is read from the nonvolatile memory 11, and the difference between the learning offset error correction value and the stored offset error correction value is calculated. In step S580, whether or not the stored offset error correction value is normal is determined based on whether or not the calculated difference is equal to or less than a predetermined threshold.

  When the difference between the learning offset error correction value and the stored offset error correction value is equal to or smaller than a predetermined threshold value, the stored offset error correction value can be regarded as normal. Therefore, the process proceeds to step S590, and it is determined to use the stored offset error correction value for correcting the rotation angle calculated from the sensor detection signal of the angle sensor 30. On the other hand, when the difference between the learning offset error correction value and the stored offset error correction value is larger than a predetermined threshold value, the stored offset error can be regarded as abnormal due to disappearance or alteration. Therefore, the process proceeds to step S600, and it is determined to use the stored offset error correction value for correcting the rotation angle calculated from the sensor detection signal of the angle sensor 30. In this case, the learning offset error correction value is written in the nonvolatile memory 11, and the stored offset error correction value is updated. Thus, the offset error correction value learning ends.

  After the end of the offset error correction value learning, the six-phase power running of the motor 20 or power generation control using the angle sensor 30 is performed in step S140 of the flowchart of FIG. That is, when the offset error correction value learning is completed, the control device 10 uses the three-phase detection stator winding in addition to the three-phase driving stator winding as the driving stator winding, and uses the motor 20 Control. For example, if the engine has not been started yet, the rotation angle calculated from the sensor detection signal of the angle sensor 30 is corrected by the offset error correction value to obtain the corrected rotation angle, and based on the corrected rotation angle By switching energization to the driving stator winding, the rotation of the motor 20 is maintained and the engine is rotated. Even when the motor 20 generates torque for assisting the engine, the rotation angle calculated from the sensor detection signal of the angle sensor 30 is corrected by the offset error correction value to obtain the correction rotation angle, and the corrected rotation angle Based on the above, energization to the driving stator winding is controlled. Furthermore, when performing power generation control, the amount of electric power collected in the in-vehicle battery is controlled by turning on and off the switching elements of the first inverter and the second inverter according to the corrected rotation angle.

  In a succeeding step S150, it is determined whether or not the ignition switch is turned off. If it is determined that the ignition switch is not turned off, the process returns to step S140. If it is determined that the ignition switch has been turned off, the processing shown in the flowchart of FIG. 2 is terminated.

  On the other hand, in step S160, which is executed when it is determined in step S100 that engine start is not required, the connection between the engine and the motor (ISG) 20 is disconnected by a belt tensioner or a clutch. As a result, the rotational load of the motor 20 is reduced, so that the position estimation of the rotor 22 and the calculation of the rotation angle can be performed with higher accuracy in the positioning control, sensorless driving, and offset error correction value learning.

  In steps S170 to S190, the same positioning control, sensorless start-up, and offset error correction value learning as in steps S110 to S130 are executed. Then, in step S210, it is determined whether or not an engine start request has been made, for example, when the ignition switch is in the start position. If it is determined that an engine start request has occurred, the process proceeds to step S210. On the other hand, if it is determined that an engine start request has not occurred, the system waits until a start request is generated.

  In step S210, the engine and the motor 20 are connected, and then in step S220, six-phase power running of the motor 20 or power generation control using the angle sensor 30 is executed in the same manner as in step S140. As described above, the six-phase power running control of the motor 20 includes control for starting the engine. In step S230, it is determined whether the ignition switch is turned off. If it is determined that the ignition switch is not turned off, the process returns to step S220. If it is determined that the ignition switch has been turned off, the processing shown in the flowchart of FIG. 2 is terminated.

(Second Embodiment)
Next, a motor control device according to the second embodiment of the present invention will be described.

  In the motor control device 10 according to the first embodiment described above, the position where the rotor 22 is positioned is estimated based on the combination of the polarities of the induced voltages induced in the three-phase detection stator winding. In contrast, in the motor control device 10 according to the present embodiment, when the rotor 22 is rotated by energizing a predetermined driving stator winding for positioning, the one-phase detection stator winding is used. Based on the polarity of the induced voltage induced and the rotation direction of the rotor 22 detected from the sensor detection signal from the angle sensor 30, the position where the rotor 22 is positioned is estimated.

  As described above, the control system includes the angle sensor 30. In order to calculate a reliable correction rotation angle using the sensor detection signal from the angle sensor 30, it is necessary to perform offset error correction value learning. However, even before the offset error correction value learning, using the sensor detection signal from the angle sensor 30, specifically, based on the order of signal changes from a plurality of Hall elements constituting the angle sensor 30, It is possible to detect the rotation direction of the rotor 22.

  If information on the rotation direction of the rotor 22 can be obtained in addition to the polarity of the induced voltage measured by the one-phase detection stator winding, as shown in FIG. 9, the three-phase detection stator winding The magnetic pole position of the rotor 22 can be estimated with a narrow range and accuracy equivalent to the case of the combination of the induced voltages measured at. This point will be described in detail below.

  When the energization is performed from the U phase to the V phase of the driving stator winding for positioning, if the initial stop position of the rotor 22 belongs to the angle ranges 4 to 9 in FIG. As described above, it can be estimated that the rotor 22 is stationary at the position C based on the negative polarity of the induced voltage measured by the X-phase stator winding.

  Next, when the initial stop position of the rotor 22 belongs to the angle ranges 1 to 3 in FIG. 6, the rotor 22 rotates in the clockwise forward direction. When the rotational angle position of the rotor 22 stops in the vicinity of the position B shown in FIG. 7B due to insufficient rotational torque, the X-phase detection stator winding measured before the stationary state The polarity of the induced voltage is positive. On the other hand, when the initial stop position of the rotor 22 belongs to the angle range 10 to 12 in FIG. 6, the rotor 22 rotates counterclockwise in the reverse direction. When the rotational angle position of the rotor 22 stops in the vicinity of the position A shown in FIG. 7A due to insufficient rotational torque, the X-phase detection stator winding measured before the stationary state The polarity of the induced voltage is positive. Thus, the position where the rotor 22 is stationary can be identified from the polarity of the induced voltage of the X phase that is the position A or the position B. The rotation direction obtained from the sensor detection signal of the angle sensor 30 can be identified.

  Therefore, also with the motor control device 10 according to the second embodiment, the rotor 22 can be positioned with a single energization, and the time required for the positioning of the rotor 22 can be shortened compared to the conventional case.

  FIG. 10 is a flowchart showing a positioning control process in the second embodiment. Steps that perform the same processing as the positioning control in the first embodiment are given the same step numbers. Since other processes are the same as those in the first embodiment described above, description thereof is omitted.

  In step S300 of the flowchart of FIG. 10, the rotor 22 is rotated by energizing a predetermined stator winding among the three-phase driving stator windings of the U phase, the V phase, and the W phase. In subsequent step S315, the polarity of the induced voltage measured by the one-phase detection stator winding is detected. In a succeeding step S320, it is determined whether or not the rotation of the rotor 22 is stopped. Further, the rotation direction of the rotor 22 is calculated based on the sensor detection signal of the angle sensor 30.

  In step S320, it is determined whether or not the rotation of the rotor 22 has stopped. Whether or not the rotation of the rotor 22 has stopped can be determined based on, for example, that the induced voltage measured by the one-phase detection stator winding has become substantially zero. If it is determined in step S320 that the rotation of the rotor 22 has stopped, the process proceeds to step S335. On the other hand, when it determines with rotation of the rotor 22 not stopping, it returns to the process of step S300. In step S335, the position where the rotor 22 is positioned is determined based on the polarity of the induced voltage of the one-phase detection stator winding detected just before the rotor 22 stops and the calculated rotation direction. presume.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the offset error correction value is measured in advance and stored in the nonvolatile memory 11. However, such prior measurement and storage of the offset error correction value may not be performed. In this case, the motor 20 is rotated by performing the above-described positioning and sensorless start, and the learning offset error correction value calculated during the rotation of the motor 20 may be used as the offset error correction value.

  Moreover, although embodiment mentioned above demonstrated the example which uses the motor 20 as an integrated starter generator, the motor 20 may be used for another use.

  In the above-described embodiment, the example in which the detection stator winding is used as the driving stator winding after the offset error correction value learning is completed has been described. However, even after the offset error correction value learning is completed, the motor 20 is driven only in three phases of the U phase, the V phase, and the Z phase, and the X phase, the Y phase, and the Z phase are used as driving stator windings. Not necessary.

DESCRIPTION OF SYMBOLS 10 ... Motor control apparatus 20 ... Motor 21 ... Stator 22 ... Rotor 30 ... Angle sensor 31 ... Detection magnet 32 ... Detection element

Claims (11)

In order to position the rotor (22) of the motor (20), among the three-phase driving stator windings (U, V, W) of the motor, positioning for energizing a predetermined driving stator winding An energization section (S300);
The rotor is rotated by energization by the positioning energization unit, and the magnetic flux acting from the rotor is changed, so that a three-phase detection stator winding (different from the three-phase driving stator winding ( A position estimation unit (S330) that estimates a position of the rotor based on a combination of polarities of induced voltages induced in X, Y, Z);
In order to rotate the rotor from a stopped state, the three-phase driving stator winding to be energized is switched according to a change in induced voltage induced in the three-phase detection stator winding. And a starting part (S120) for changing the driving stator winding for starting energization according to the position of the rotor estimated by the position estimating part. Motor control device. A first rotation angle calculation unit (S550) that calculates a rotation angle of the rotor based on a detection signal from an angle sensor (30) that outputs a detection signal corresponding to the rotation angle of the rotor;
Based on the induced voltage induced in the three-phase detection stator winding while the rotor is rotating by energization of the driving stator winding by the starter, the rotor A second rotation angle calculation unit (S540) for calculating a rotation angle;
From the difference between the rotation angle of the rotor calculated by the first rotation angle calculation unit and the rotation angle of the rotor calculated by the second rotation angle calculation unit, the mounting error of the angle sensor to the motor is reduced. The motor control device according to claim 1, further comprising: a correction value calculation unit (S560) that calculates a correction value for correcting an offset error caused by the offset error. A first rotation angle calculation unit (S550) that calculates a rotation angle of the rotor based on a detection signal from an angle sensor that outputs a detection signal corresponding to the rotation angle of the rotor;
A storage unit (11) for storing a correction value for correcting an offset error between a rotation angle of the rotor based on a detection signal from the angle sensor and an actual rotation angle of the rotor;
Rotation of the rotor based on the induced voltage induced in the three-phase detection stator winding while the rotor is rotating by energization of the driving stator winding by the starter A second rotation angle calculation unit (S540) for calculating an angle;
The difference between the rotation angle of the rotor calculated by the first rotation angle calculation unit and the rotation angle of the rotor calculated by the second rotation angle calculation unit, and the correction value stored in the storage unit A determination unit (S570, S580) for determining an abnormality of the correction value by comparing; and
The motor control according to claim 1, further comprising: a correction value update unit (S600) that calculates a correct correction value and stores the correction value in the storage unit when the determination unit determines that the correction value is abnormal. apparatus. In order to position the rotor (22) of the motor (20), among the three-phase driving stator windings (U, V, W) of the motor, positioning for energizing a predetermined driving stator winding An energization section (S300);
A rotation direction detection unit (S315) that detects a rotation direction of the rotor when the rotor is rotated by energization by the positioning energization unit;
The rotor is rotated by energization by the positioning energization unit, and the magnetic flux acting from the rotor is changed, so that a one-phase detection stator winding (different from the three-phase driving stator winding ( A position estimation unit (S335) for estimating the position of the rotor based on the polarity of the induced voltage induced in X) and the rotation direction of the rotor detected by the rotation direction detection unit;
In order to rotate the rotor from a stopped state, the three-phase driving stator winding to be energized is switched according to a change in induced voltage induced in the three-phase detection stator winding. And a starting part (S120) for changing the driving stator winding for starting energization according to the position of the rotor estimated by the position estimating part. Motor control device. The rotation direction detection unit detects a rotation direction of the rotor based on a detection signal from an angle sensor (30) that outputs a detection signal corresponding to a rotation angle of the rotor.
The motor is provided with the three-phase detection stator winding (X, Y, Z),
A first rotation angle calculation unit (S550) for calculating a rotation angle of the rotor based on a detection signal from the angle sensor;
Based on the induced voltage induced in the three-phase detection stator winding while the rotor is rotating by energization of the driving stator winding by the starter, the rotor A second rotation angle calculation unit (S540) for calculating a rotation angle;
From the difference between the rotation angle of the rotor calculated by the first rotation angle calculation unit and the rotation angle of the rotor calculated by the second rotation angle calculation unit, the mounting error of the angle sensor to the motor is reduced. The motor control device according to claim 4, further comprising: a correction value calculation unit (S560) that calculates a correction value for correcting an offset error caused by the offset error. The rotation direction detection unit detects a rotation direction of the rotor based on a detection signal from an angle sensor (30) that outputs a detection signal corresponding to a rotation angle of the rotor.
The motor is provided with the three-phase detection stator winding (X, Y, Z),
A first rotation angle calculation unit (S550) for calculating a rotation angle of the rotor based on a detection signal from the angle sensor;
A storage unit (11) for storing a correction value for correcting an offset error between a rotation angle of the rotor based on a detection signal from the angle sensor and an actual rotation angle of the rotor;
Rotation of the rotor based on the induced voltage induced in the three-phase detection stator winding while the rotor is rotating by energization of the driving stator winding by the starter A second rotation angle calculation unit (S540) for calculating an angle;
The difference between the rotation angle of the rotor calculated by the first rotation angle calculation unit and the rotation angle of the rotor calculated by the second rotation angle calculation unit, and the correction value stored in the storage unit A determination unit (S570, S580) for determining an abnormality of the correction value by comparing; and
The motor control according to claim 4, further comprising: a correction value updating unit (S600) that calculates a correct correction value and stores the correction value in the storage unit when the determination unit determines that the correction value is abnormal. apparatus.   The position estimation unit is configured to supply a current to the predetermined driving stator winding at a first position where a magnetic field direction when energizing the predetermined driving stator winding and a magnetic field direction of the rotor are opposed to each other. From the magnetic field direction at the time, from the second position where the magnetic field direction of the rotor is advanced by 90 ° in electrical angle in the first rotation direction, and from the magnetic field direction when energizing the predetermined driving stator winding, Any one of the third positions where the magnetic field direction of the rotor is delayed by 90 ° in electrical angle in the first rotation direction is estimated as the position where the rotor is positioned. The motor control device according to item.   7. The three-phase detection stator winding and the three-phase driving stator winding are provided alternately along the rotation direction of the rotor. The motor control device according to item 1. Control for controlling switching of energization to the driving stator winding of the motor based on the rotation angle obtained by correcting the rotation angle of the rotor calculated from the detection signal from the angle sensor using the correction value Part (S140),
The motor control device according to claim 8, wherein the control unit uses the three-phase detection stator winding as the driving stator winding in addition to the three-phase driving stator winding. The motor is an integrated starter generator that is connected to an engine to start the engine, assist engine torque, and generate electric power.
A mechanism capable of opening the connection state between the motor and the engine is provided;
The positioning of the rotor by the positioning energization unit and the rotation of the rotor by the starting unit are performed when the connection state between the motor and the engine is released by the mechanism. The motor control device according to any one of the above. The motor is an integrated starter generator that is connected to an engine to start the engine, assist engine torque, and generate electric power.
When the motor starts the engine, if the positioning of the rotor by the positioning energization unit and the rotation of the rotor by the starter are performed, the starter The motor control device according to any one of claims 1 to 9, wherein the rotation of the rotor is stopped and the motor is rotated by the rotation of the engine.

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