JP2021044943A - Vehicle motor control device - Google Patents

Abstract

To provide a vehicle motor control device capable of accurately learning an offset angle even for a motor having possibility of reverse rotation.SOLUTION: In a case in which an offset angle calibration unit (33) of a vehicle motor control device (100) controls a current control unit (39) to supply a predetermined starting current to a synchronous motor (11), when the synchronous motor (11) rotates in the reverse direction, the offset angle calibration unit controls the current control unit (39) such that the offset angle is inverted by 180°, and learns the offset angle after the synchronous motor (11) has been rotated in the forward direction.SELECTED DRAWING: Figure 5

Description

The present invention relates to a vehicle motor control device.

Conventionally, a vector-controlled three-phase AC motor is known as a synchronous motor used in an electric vehicle or the like. In such a synchronous motor, the rotor rotates in synchronization with the rotating magnetic field of the stator. Therefore, it is necessary to accurately detect the rotation angle position of the rotor by the rotation angle sensor. However, when the rotation angle sensor is used to determine the angle position of the rotor, the detected angle position of the rotor will be inaccurate unless the detection angle of the rotation angle sensor is correctly calibrated to be the electric angle of the actual motor. Therefore, the synchronous motor cannot be controlled with high accuracy.

On the other hand, the rotor angle detected by the rotation angle sensor by detecting the deviation between the detection angle of the rotation angle sensor and the electric angle of the actual motor (hereinafter, this deviation is also referred to as "offset angle"). A technique for correcting the position is disclosed (see, for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2017-163699 Japanese Unexamined Patent Publication No. 2010-148271

However, the techniques described in Patent Documents 1 and 2 detect the rotation angle of the motor that can be connected to the engine, and the rotation of the engine can be used to rotate the motor in the positive direction from the outside. It is assumed. On the other hand, when the motor is not provided with a means for rotating the motor from the outside, such as a drive motor for an electric vehicle, the angle position to be detected is detected when the offset angle of the rotation angle sensor is not calibrated correctly. Depending on the error, the motor may rotate in the reverse direction when current is supplied.

The present invention has been made in view of the above problems, and provides a vehicle motor control device capable of accurately learning the offset amount even when the motor rotates in the reverse direction.

According to a certain aspect of the present invention, it is a vehicle motor control device that vector-controls a synchronous motor that outputs a driving force of a vehicle based on a sensor signal of a rotation angle sensor, and is an angular position and a rotation direction of a rotor of the synchronous motor. The rotation angle sensor that detects the above, the offset angle calibration unit that learns the offset angle for correcting the angle position detected by the rotation angle sensor, and the angle position detected by the rotation angle sensor are corrected by the offset angle. A current control unit that controls the supply current of the synchronous motor based on the corrected angle position is provided, and the offset angle calibration unit controls the current control unit so as to supply a predetermined starting current to the synchronous motor. Provided is a vehicle motor control device that learns the offset angle after controlling the current control unit to reverse the offset angle by 180 ° to rotate the synchronous motor in the forward direction when the synchronous motor rotates in the reverse direction. To.

As described above, according to the present invention, the offset angle can be learned accurately even when the motor rotates in the reverse direction.

It is a block diagram which shows the structural example of the motor control device for a vehicle which concerns on embodiment of this invention. It is a flowchart which shows the process of learning the offset angle by the vehicle motor control device which concerns on the same embodiment. It is a timing chart which shows an example of the case where the process of learning an offset angle is executed. It is explanatory drawing which shows the deviation of the current vector of a starting current. It is explanatory drawing which shows the state which the current vector of a starting current was inverted by 180 °. It is explanatory drawing which shows the offset angle which is learned.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Overall configuration of vehicle motor control device>
First, an example of the overall configuration of the vehicle motor control device according to the present embodiment will be described. FIG. 1 is a block diagram showing a configuration example of a vehicle motor control device 100.

The vehicle motor control device 100 according to the present embodiment is a control device that controls a three-phase AC type synchronous motor 11 as a motor that outputs a driving force of a vehicle such as an electric vehicle. Examples of the synchronous motor 11 include a permanent magnet motor, an excitation drive motor, and a stepping motor, but the synchronous motor 11 is not limited to these motors.

The synchronous motor 11 includes a rotation angle sensor 15 that detects the angular position γ * of the rotor 13. The rotation angle sensor 15 can detect not only the angular position γ * of the rotor 13 but also the rotation direction of the synchronous motor 11. Examples of such a rotation angle sensor 15 include, but are not limited to, an increment type position sensor, an absolute position detection sensor such as a resolver and a rotary encoder, and a Hall element.

The vehicle motor control device 100 includes a basic vector calculation unit 21, a command vector calculation unit 23, a vector / phase conversion unit 25, a two-phase / three-phase conversion unit 27, an inverter 29, current sensors 31u, 31v, 31w, and offset angle calibration. A unit 33, a three-phase / two-phase conversion unit 35, and a phase / vector conversion unit 37 are provided.

The basic vector calculation unit 21 calculates the basic current vectors id * and iq * in the dq coordinate system based on the torque command value Trq of the torque command output unit 110 that outputs the torque command value Trq of the synchronous motor 11. The torque command output unit 10 may be, for example, a component device connected to the vehicle motor control device 100 when performing calibration work of the synchronous motor 11 mounted on the vehicle, and the calibration work is performed. The program may be set to output a predetermined torque command value Trq at the time of operation.

The command vector calculation unit 23 is the current vector id, iq of the current synchronous motor 11 obtained from the basic current vectors id *, iq * calculated by the basic vector calculation unit 21 and the detected values of the current sensors 31u, 31v, 31w. Based on the above, the voltage (current) command vectors Vd and Vq in the dq coordinate system are calculated. For example, the command vector calculation unit 23 is configured to perform PI calculation based on the basic current vectors id *, iq * and the current vectors id, iq, and calculate the voltage command vectors Vd, Vq. It is not limited to simple operations.

The vector / phase conversion unit 25 converts the voltage command vectors Vd and Vq calculated by the command vector calculation unit 23 into two-phase command values Vα and Vβ in the rotating coordinate system of the angular position γ of the rotor 13.

The two-phase / three-phase conversion unit 27 converts the two-phase command values Vα and Vβ converted by the vector / phase conversion unit 25 into three-phase command values Vu, Vv and Vw and outputs them to the inverter 29. The two-phase / three-phase conversion unit 27 converts the two-phase command values Vα and Vβ into the three-phase command values Vu, Vv and Vw using the correct angle position γ of the rotor 13 output from the offset angle calibration unit 33.

The inverter 29 PWM-controls the supply currents of the U, V, and W phases of the synchronous motor 11 based on the three-phase command values Vu, Vv, and Vw converted by the two-phase / three-phase converter 27. , DC power is converted into AC power and supplied to the synchronous motor 11.

The current sensors 31u, 31v, and 31w detect the supply current values iu, iv, and iw of each phase of the U, V, and W of the synchronous motor 11, respectively.

The offset angle calibration unit 33 learns the offset angle γoff for correcting the angle position γ * detected by the rotation angle sensor 15. Further, the offset angle calibration unit 33 calibrates the angle position γ * detected by the rotation angle sensor 15 with the learned offset angle γ off, and outputs the correct angle position γ (= γ * −γ off). In the present embodiment, the offset angle calibration unit 33 controls the supply current so that the rotation direction of the synchronous motor 11 (rotor 13) is the direction of forward rotation, and then executes control to learn a predetermined offset angle. .. The learning control method executed in the state where the synchronous motor 11 rotates in the forward direction can appropriately adopt a conventionally known method, and is not particularly limited.

The three-phase / two-phase conversion unit 35 converts the supply current values iu, iv, and iw of each of the U, V, and W phases detected by the current sensors 31u, 31v, and 31w into the two-phase detection values. The three-phase / two-phase conversion unit 35 detects the supply current values iu, iv, and iw of each of the U, V, and W phases in two phases using the correct angle position γ of the rotor 13 output from the offset angle calibration unit 33. Convert to a value.

The phase / vector conversion unit 37 converts the two-phase detection value converted by the three-phase / two-phase conversion unit 35 into current vectors id and iq in the dq coordinate system, and outputs them to the command vector calculation unit 23.

In the vehicle motor control device 100 according to the present embodiment, the basic vector calculation unit 21, the command vector calculation unit 23, the vector / phase conversion unit 25, the two-phase / three-phase conversion unit 27, the offset angle calibration unit 33, 3 The phase / two-phase conversion unit 35 and the phase / vector conversion unit 37 function as the current control unit 39.

<2. Offset angle learning process>
Up to this point, an example of the overall configuration of the vehicle motor control device 100 according to the present embodiment has been described. Next, a process of learning the offset angle γoff of the rotation angle sensor 15 by the vehicle motor control device 100 according to the present embodiment will be described. FIG. 2 is a flowchart showing a process of learning the offset angle γoff. In the present embodiment, the vehicle motor control device 100 is configured to execute the flowchart shown in FIG. 2, but the upper control device of the vehicle motor control device 100 learns the offset amount γoff. You may do it.

The vehicle motor control device 100 synchronizes when a predetermined starting current is supplied to the synchronous motor 11 in learning the offset angle γoff for correcting the angular position γ * detected by the rotation angle sensor 15. When the motor 11 rotates in the reverse direction, the supply current is controlled so as to reverse the offset amount by 180 ° to rotate the synchronous motor 11 in the forward direction, and the offset angle γoff is learned.

The offset angle learning process is performed, for example, in an inspection step after the incorporation of the synchronous motor 11 into the vehicle is completed. Therefore, it is preferable that the learning process is executed in a state where the synchronous motor 11 may rotate forward or reverse. For example, the learning process may be executed with the electric vehicle equipped with the synchronous motor 11 installed on the chassis dynamometer device.

First, the torque command output unit 110 issues a command (hereinafter, also referred to as “torque output command”) to the vehicle motor control device 100 to output torque for rotating the synchronous motor 11 in the forward direction. It is transmitted to the control device 100 (step S11). When the torque output command is output, the current control unit 39 of the vehicle motor control device 100 supplies the starting current to the synchronous motor 11. The starting current is a current that can rotate the synchronous motor 11 in the positive direction, and is a current that becomes a current vector (q-axis current vector) in the q-axis direction of the dq coordinate system when the offset angle γoff is correctly learned. is there.

In the offset angle learning process in the present embodiment, since the rotation direction of the synchronous motor 11 is determined at the start of the learning process, the starting current may be at least a current having a magnitude capable of rotating the synchronous motor 11. Further, in order to suppress the impact when the synchronous motor 11 rotates in the reverse direction, it is preferable that the supplied starting current is gradually increased from a small value.

Next, the offset angle calibration unit 33 detects the rotation direction of the synchronous motor 11 based on the sensor signal of the rotation angle sensor 15 (step S13).

Next, the offset angle calibration unit 33 determines whether or not the synchronous motor 11 is rotating based on the detection result in the rotation direction (step S15). When it is not determined that the synchronous motor 11 is rotating (S15 / No), the offset angle calibration unit 33 offsets the current vector of the dq coordinate system of the starting current output in step S11 by 90 °, and the offset angle (hereinafter referred to as the offset angle). , Γoff_A (also referred to as “forced rotation offset angle”) is stored in a storage element (not shown) (step S17).

When the synchronous motor 11 is mounted with a deviation of 90 °, the current vector of the starting current output in step S11 coincides with the d-axis direction of the dq coordinate system, and becomes the current of the d-axis current vector to rotate the synchronous motor 11. It will be in a state where it does not. Therefore, in step S17, a process of offsetting the current vector by 90 ° is performed in order to generate a current component in the q-axis direction and rotate the synchronous motor 11. The direction of offsetting the current vector by 90 ° may be either the forward direction or the reverse direction.

When it is determined in step S15 that the synchronous motor 11 is rotating (S15 / Yes), or in step S17, the current vector is offset by 90 ° to rotate the synchronous motor 11, and then the offset angle calibration unit. 33 determines whether or not the rotation direction of the synchronous motor 11 is the forward rotation direction (step S19).

In step S19, when it is not determined that the rotation direction of the synchronous motor 11 is the forward rotation direction (S19 / No), the torque command output unit 110 offsets the current vector of the dq coordinate system of the current starting current by 180 °. The offset angle (hereinafter, also referred to as “reversal offset angle”) γoff_B is stored in a storage element (not shown) (step S21). When the rotation direction of the synchronous motor 11 is not the forward rotation direction, that is, when the synchronous motor 11 is rotating in the reverse direction, the synchronous motor 11 can be rotated in the forward rotation direction by reversing the current vector.

In step S19, when it is determined that the rotation direction of the synchronous motor 11 is the forward rotation direction (S19 / Yes), or in step S21, the current vector is offset by 180 ° to rotate the synchronous motor 11 in the forward direction. After that, the offset angle calibration unit 33 sets a flag that allows learning of the offset angle γoff (step S23).

Next, the offset angle calibration unit 33 determines whether or not the rotation speed of the synchronous motor 11 is suitable for learning the offset angle based on the sensor signal of the rotation angle sensor 15 (step S25). As the speed suitable for learning the offset angle, an appropriate range is set according to the type and performance of the synchronous motor 11 and the content of the offset angle learning process to be performed.

When it is not determined that the rotation speed of the synchronous motor 11 is suitable for learning the offset angle (S25 / No), the offset angle calibration unit 33 has elapsed time since the torque output command was output in step S11. Determines whether or not the preset maximum time has been reached (step S33). This maximum time usually defines the maximum time until the rotation speed of the synchronous motor 11 reaches an appropriate range. If the rotation speed of the synchronous motor 11 does not reach the appropriate range even if the maximum time is exceeded, there is some problem with the synchronous motor 11 or the vehicle motor control device 100, and the offset angle learning process cannot be performed properly. It is estimated to be.

If it is not determined that the elapsed time has reached the maximum time (S33 / No), the process returns to step S25, and the offset angle calibration unit 33 determines whether the rotation speed of the synchronous motor 11 is suitable for learning the offset angle. Repeat the discrimination. On the other hand, when it is determined that the elapsed time has reached the maximum time (S33 / Yes), the offset angle calibration unit 33 sets a flag indicating that the offset angle learning process has not been properly performed (step S37). ), End the process of learning the offset angle. In this case, since the synchronous motor 11 cannot be controlled accurately, the vehicle to be inspected may be determined to be incompatible with the inspection.

On the other hand, when it is determined in step S25 above that the rotation speed of the synchronous motor 11 is a speed suitable for learning the offset angle (S25 / Yes), the offset angle calibration unit 33 has a predetermined offset angle. The learning control is executed (step S27). As a result, the basic offset angle γoff_C is obtained. As the learning control executed in step S27, a conventionally known learning control can be appropriately adopted. That is, even if the synchronous motor 11 can rotate in the reverse direction, the conventional synchronous motor 11 is positive because the rotation direction of the synchronous motor 11 is the forward rotation direction by the above-mentioned processes from step S13 to step S21. Learning control that assumes that it is rotating can be applied.

After executing the learning control of the predetermined offset angle, the offset angle calibration unit 33 reverses the stored forced rotation offset angle γoff_A (= 90 ° or −90 °) with respect to the obtained basic offset angle γoff_C. The offset angle γoff_B (= 180 °) is added to calculate the offset angle γoff (= γoff_C + γoff_A + γoff_B).

When the starting current is supplied by the torque output command transmitted in step S11 and the synchronous motor 11 rotates forward, the basic offset angle γoff_C is learned as the offset angle γoff as it is. On the other hand, if the synchronous motor 11 does not rotate even if the starting current is supplied by the torque output command, or if the synchronous motor 11 rotates in the reverse direction, at least one of the forced rotation offset angle γoff_A and the reverse offset angle γoff_B. Is added to the basic offset angle γoff_C to obtain the offset angle γoff.

Next, the offset angle calibration unit 33 determines whether or not the offset angle learning has been properly performed (step S29). For example, when the calculated offset angle γoff becomes an abnormal value, the offset angle calibration unit 33 is prevented from determining that the offset angle has been properly learned. When it is determined that the offset angle learning is properly performed (S29 / Yes), the offset angle calibration unit 33 sets a flag indicating that the learned offset angle γoff is appropriate (step S31), and sets the offset angle. Ends the process of learning.

Next, with reference to FIGS. 3 to 6, an example of a case where the process of learning the offset angle is executed according to the flowchart shown in FIG. 2 will be specifically described. FIG. 3 is a timing chart showing an example of a case where the process of learning the offset angle is executed according to the flowchart shown in FIG. 4 to 6 are explanatory views showing an offset angle of the starting current.

It is assumed that the rotation speed (rpm_EM) of the synchronous motor 11 changes to minus when the torque output command (Com_T) is output at time t1. As shown in FIG. 4, this is due to the fact that the mounting position of the synchronous motor 11 is displaced even though the command for supplying the current of the current vector (crt_iq) in the q-axis direction of the dq coordinate system is output. When the current of the detection current vector (msd_iq) is supplied, the synchronous motor 11 rotates in the reverse direction.

At time t2, when the offset angle calibration unit 33 detects the reverse rotation of the synchronous motor 11, the offset angle (γ_os) of the current vector is inverted by 180 °. Along with this, as shown in FIG. 5, the detection current vector (msd_iq) is inverted by 180 °, and the rotation speed (rpm_EM) of the synchronous motor 11 begins to switch in the forward rotation direction. At time t3, when the rotation direction of the synchronous motor 11 becomes the forward rotation direction, the offset angle calibration unit 33 sets a flag (F_olr) that allows learning of the offset angle γoff.

At time t4, when the rotation speed (rpm_EM) of the synchronous motor 11 reaches a range (rng_ol) suitable for learning the offset angle, the offset angle calibration unit 33 executes the learning control (OL) of the predetermined offset angle. As shown in FIG. 6, the offset angle learning control (OL) obtains the basic offset angle γoff_C between the current vector whose offset angle is inverted by 180 ° and the q-axis. At time t5, the offset angle calibration unit 33 adds the inversion offset angle γoff_B (= 180 °) to the basic offset angle γoff_C obtained by the offset angle learning control (OL) to obtain the offset angle γoff (FIG. 6). (See), and set a flag (F_oa) indicating that the learned offset angle γoff is appropriate.

After that, at time t6, the output of the torque output command (Com_T) is stopped, and the rotation of the synchronous motor 11 is stopped. After the process of learning the offset angle is completed, the offset angle calibration unit 33 uses the corrected angle position obtained by correcting the angle position of the rotor 13 detected by the rotation angle sensor 15 with the offset angle γoff, and the synchronous motor 11 Is set to vector control.

As described above, according to the vehicle motor control device 100 according to the present embodiment, when the starting current of the q-axis current vector is supplied to the synchronous motor 11 in learning the offset angle γoff, the synchronous motor 11 causes the synchronous motor 11. When the motor is rotating in the reverse direction, the current vector is inverted by 180 ° to rotate the synchronous motor 11 in the forward direction, and then the learning control of the offset angle γoff is executed. Therefore, even if the synchronous motor 11 can rotate in the reverse direction, the offset angle γoff of the synchronous motor 11 can be learned by adopting the conventional offset angle learning control assuming the forward rotation of the synchronous motor 11. ..

Further, the vehicle motor control device 100 according to the present embodiment can adopt the conventional offset angle learning control premised on the forward rotation of the synchronous motor 11 without requiring an additional circuit or sensor, and thus is a component. It can be applied to a synchronous motor 11 that can rotate in the reverse direction without increasing the cost. Further, since the conventional learning control can be adopted for the offset angle learning control itself, software changes can be minimized.

Further, the vehicle motor control device 100 according to the present embodiment adds a control logic for changing the current vector of the starting current, so that the synchronous motor 11 can be rotated even if the vehicle does not have a means for rotating the synchronous motor 11 from the outside. The offset angle can be learned while the 11 is rotated by itself. Therefore, the offset angle can be learned without the risk of heat generation of the synchronous motor 11.

Further, since the vehicle motor control device 100 according to the present embodiment gradually increases the current value of the starting current from a small value, the impact can be reduced even when the synchronous motor 11 rotates in the reverse direction.

Further, the vehicle motor control device 100 according to the present embodiment offsets the current vector by 90 ° when the synchronous motor 11 is not rotating when the starting current is supplied. Therefore, even if the starting current is actually the current of the d-axis current vector, the synchronous motor 11 can be rotated as the current of the q-axis current vector.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical idea described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

For example, the vehicle motor control device 100 according to the above embodiment is a vehicle motor control device that controls a synchronous motor 11 mounted on an electric vehicle, but the present invention is not limited to such an example. The synchronous motor may be a synchronous motor of a hybrid vehicle having an engine and a synchronous motor as a power source.

11 ... Synchronous motor, 13 ... Rotor, 15 ... Rotation angle sensor, 33 ... Offset angle calibration unit, 39 ... Current control unit, 100 ... Vehicle motor control device

Claims (5)

In the vehicle motor control device (100) that vector-controls the synchronous motor (11) that outputs the driving force of the vehicle based on the sensor signal of the rotation angle sensor (15).
A rotation angle sensor (15) that detects the angular position and rotation direction of the rotor (13) of the synchronous motor (11), and
An offset angle calibration unit (33) that learns an offset angle (γoff) for correcting the angle position detected by the rotation angle sensor (15), and an offset angle calibration unit (33).
A current control unit (11) that controls the supply current of the synchronous motor (11) based on the corrected angle position obtained by correcting the angle position detected by the rotation angle sensor (15) with the offset angle (γoff). 39) and
The offset angle calibration unit (33)
When the current control unit (39) is controlled so as to supply a predetermined starting current to the synchronous motor (11), if the synchronous motor (11) rotates in the reverse direction, the offset angle is reversed by 180 °. A vehicle motor control device that learns an offset angle after controlling the current control unit (39) to rotate the synchronous motor (11) in the forward direction. The current control unit (39) gradually increases the current value when supplying the starting current.
The vehicle motor control device according to claim 1. The offset angle calibration unit (33) learns the offset angle (γoff) by adding 180 ° to the basic offset angle (γoff_C) learned after reversing the offset angle by 180 °.
The vehicle motor control device according to claim 1 or 2. The offset angle calibration unit (33) offsets the current vector of the starting current by 90 ° when the synchronous motor (11) is not rotating while the starting current is supplied.
The vehicle motor control device according to any one of claims 1 to 3. In the offset angle calibration unit (33), the rotation speed of the synchronous motor (11) is suitable for learning the offset angle from the state in which the synchronous motor (11) is rotated in the normal direction to the elapse of a preset maximum time. If the proper range is not reached, the learning of the offset angle is terminated.
The vehicle motor control device according to any one of claims 1 to 4.

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