JP6629129B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device.

  A switch reluctance motor (hereinafter, SR motor) has a salient pole (protruding pole) structure for both a stator and a rotor. The SR motor forms a magnetizing coil by winding each of the plurality of salient poles of the stator, and selectively energizes the magnetizing coils to magnetically attract the salient poles of the rotor to the salient poles of the stator. Drive the rotation of the rotor. For this reason, the SR motor does not require permanent magnets or windings on the rotor, has a simple motor structure, is inexpensive, and has the advantages of being mechanically robust, capable of high rotation, and usable in high temperature environments. ing. For this reason, SR motors are used for various purposes, and for example, are also used as motors in electric vehicles (for example, see Patent Document 1).

  For example, as an energization method for driving a three-phase SR motor, a so-called 120-degree rectangular wave energization in which the energization angle of each phase is 120 degrees is most commonly used. However, as shown in FIG. 9, in the conventional 120-degree rectangular wave energization, when the SR motor is rotating at an extremely low speed (for example, when the SR motor is started), a large torque ripple occurs when the energization is switched to each phase. In some cases. As a method of suppressing the torque ripple, as shown in FIG. 10, when the energization to each phase is switched, a period in which the two phases before and after the energization are simultaneously energized (hereinafter, referred to as an “overlap section”) is provided. There is a method.

JP 2015-23749 A

  However, in this overlap section, since two-phase torque is applied to the SR motor, an excessive torque may be generated in the SR motor. Further, vibration or noise may be generated due to the influence of the sharp change of the excessive torque generated in the SR motor.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a motor control device capable of reducing a torque change occurring in an overlap section.

One aspect of the present invention is a motor control device that rotationally drives the SR motor by switching energization of coils corresponding to each phase of a multi-phase SR motor, wherein the energized phase is changed from one phase to the other phase. When switching to, an energization timing output unit that provides an overlap section for energizing both the one phase and the other phase, a position detection unit that detects the rotational position of the rotor of the SR motor, A rotation speed detection unit that detects a rotation speed of the rotor based on the rotation position detected by the position detection unit, and at least a part of the overlap section, at least one of the one phase and the other phase. life and one of the current control unit for gradually changing the current flowing in the phase, the current command value is a target value of the current supplied to each phase in accordance with the accelerator signal indicating the operation amount of an accelerator A current command value generating unit, and the rotor that gradually changes the current based on the current command value generated by the current command value generating unit and the rotation speed detected by the rotation speed detection unit. A command inclination width determination unit that determines a command value inclination width indicating the width of the rotation position, and the current command value of the overlap section, the current rotation position detected by the position detection unit and the command value inclination. A current command value correction unit that corrects using the width,
The current control unit, in the inclined energization section, by controlling the current flowing to each phase based on the current command value corrected by the current command value correction unit, the one phase A motor control device characterized by gradually changing a current flowing in at least one of the other phases .

  One embodiment of the present invention is the above-described motor control device, wherein the current control unit is configured to control the one phase after the SR motor rotates by a predetermined angle from a timing when a current flows to the other phase. Gradually decrease the current flowing through the

  One embodiment of the present invention is the above-described motor control device, wherein the current control unit gradually increases the current flowing to the other phase, and the current value flowing to the other phase reaches a threshold value. Then, after the SR motor rotates by a predetermined angle, the current flowing in the one phase is gradually reduced.

  One embodiment of the present invention is the above-described motor control device, further including a low-side switching element and a high-side switching element connected to the coil, wherein the current control unit includes the PWM control is performed on the ON state or the OFF state of both the low-side switching element and the high-side switching element at the same time.

  As described above, according to the present invention, it is possible to provide a motor control device capable of reducing a torque change occurring in an overlap section.

1 is a configuration diagram of an electric vehicle system 100 to which a motor control device 1 according to a first embodiment is applied. FIG. 1 is a diagram illustrating an example of a schematic configuration of a motor control device 1 according to a first embodiment. FIG. 5 is a diagram illustrating a current command value correction process of a current command value correction unit according to the first embodiment. It is a figure showing the flow of processing which corrects the current command value of control device 13 in a 1st embodiment. FIG. 9 is a configuration diagram of an electric vehicle system 100A to which a motor control device 1A according to a second embodiment is applied. It is a figure showing an example of the schematic structure of motor control device 1A in a 2nd embodiment. It is a figure explaining the correction processing of the electric current command value of electric current command value amendment part 142A in a 2nd embodiment. FIG. 9 is a diagram for explaining PWM control of an ON state or an OFF state of the low-side switching element and the high-side switching element of the drive circuit 12 according to the first and second embodiments. It is a figure explaining conventional 120 degree rectangular wave energization. It is a figure explaining the conventional method of providing an overlap section by two-phase energization.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all combinations of the features described in the embodiments are necessarily indispensable to the solution of the invention. In the drawings, the same or similar parts are denoted by the same reference numerals, and redundant description may be omitted.

The motor control device according to the embodiment, when switching the energized phase in the multi-phase SR motor from one phase to the other phase, at least one of the overlap sections energizing both the one phase and the other phase. In the section, the current flowing in at least one of the one phase and the other phase is gradually changed.
Hereinafter, a motor control device according to an embodiment will be described with reference to the drawings.

(1st Embodiment)
Hereinafter, the motor control device 1 according to the first embodiment will be described with reference to the drawings.
FIG. 1 is a configuration diagram of an electric vehicle system 100 to which the motor control device 1 according to the first embodiment is applied.
The electric vehicle system 100 according to the first embodiment includes a motor control device 1, an accelerator pedal 4, an accelerator operation detection unit 5, a shift position sensor 6, an SR motor 7, a rotation angle sensor 8, and a battery 9.

  The accelerator operation detecting unit 5 detects an input device for selecting a driving force of an accelerator operated by a driver, for example, an operation amount (a pedaling force amount) of an accelerator pedal 4. The accelerator operation detector 5 outputs an accelerator signal corresponding to the operation amount of the accelerator pedal 4 to the motor control device 1. For example, the accelerator operation detection unit 5 has a variable resistor, and connects the accelerator pedal 4 and a knob that controls the resistance value of the variable resistor with a rigid member. Then, the accelerator operation detecting unit 5 detects the voltage divided by the variable resistor that changes according to the operation amount of the accelerator pedal 4, and outputs the detected voltage to the motor control device 1 as an accelerator signal. The accelerator operation detection unit 5 may include a pressure sensor or the like that detects the amount of depression of the accelerator pedal 4 and may output the detection result to the motor control device 1 as an accelerator signal.

  The shift position sensor 6 is connected to the motor control device 1. The shift position sensor 6 detects the position of a shift lever (not shown) provided in the driver's seat. The shift position sensor 6 outputs a shift signal indicating the position of the shift lever to the motor control device 1. Accordingly, the motor control device 1 determines which of the plurality of shift positions has been selected based on the shift signal acquired from the shift position sensor 6. For example, the plurality of shift positions include a traveling position and a reverse traveling position.

The SR motor 7 is a polyphase SR motor that drives the rear wheel 11 via the rear gear 10. Details of the SR motor 7 will be described later.
The rotation angle sensor 8 is provided in the SR motor 7. The rotation angle sensor 8 is a detection device that detects the rotation angle of the rotor of the SR motor 7, and is, for example, a resolver. The rotation angle sensor 8 outputs an output signal corresponding to the detected rotation angle to the motor control device 1.

The motor control device 1 rotates the SR motor 7 by switching the energization of coils (described later) corresponding to each phase of the SR motor 7.
The motor control device 1 acquires an accelerator signal from the accelerator operation detection unit 5. The motor control device 1 acquires a shift signal from the shift position sensor 6. The motor control device 1 acquires an output signal of a rotation angle sensor 8 that detects the rotation speed of the SR motor 7. The motor control device 1 determines a direction in which the SR motor 7 is rotated based on the shift signal. Then, the motor control device 1 calculates a current command value which is a target value of the current flowing to the SR motor 7 based on the accelerator signal. The motor control device 1 performs feedback control so that the value of the current flowing through the SR motor 7 becomes the calculated current command value.

Hereinafter, the motor control device 1 for the SR motor 7 in the first embodiment will be specifically described. FIG. 2 is a diagram illustrating an example of a schematic configuration of the motor control device 1 according to the first embodiment.
As shown in FIG. 2, the motor control device 1 according to the first embodiment includes a drive circuit 12 and a control device 13.

  For example, the SR motor 7 includes a rotor 31 having four salient pole portions, and a stator 32 provided to surround the rotor 31 and having six salient pole portions toward the inner rotor. Therefore, the rotation angle sensor 8 detects the rotation angle of the rotor 31.

  The six salient pole portions of the stator 32 are respectively wound to form an exciting coil, and coils Lu, Lv, and Lw are formed with a pair of opposing salient pole portions. When the coils Lu, Lv, Lw are selectively energized, the salient poles of the stator 32 magnetically attract the salient poles of the rotor 31 to generate a driving torque on the rotor 31. As a result, the SR motor 7 rotates.

The drive circuit 12 is connected to the battery 9. The drive circuit 12 includes a capacitor 51, switching elements 52 to 57, and diodes 58 to 63.
For example, the switching elements 52 to 57 may be configured by any one of an IGBT (Insulated gate bipolar transistor), an FET (Field Effective Transistor), and a BJT (Bipolar junction transistor). In the present embodiment, a case will be described in which the switching elements 52 to 57 are n-channel FETs.

The capacitor 51 has one end connected to the positive electrode of the battery 9 and the other end connected to the negative electrode of the battery 9.
The switching element 52 has a drain connected to the positive electrode of the battery 9 and a source connected to the cathode of the diode 58. The anode of diode 58 is connected to the negative electrode of battery 9. The diode 59 has a cathode connected to the positive electrode of the battery 9 and an anode connected to the drain of the switching element 53. The source of the switching element 53 is connected to the negative electrode of the battery 9.

The switching element 54 has a drain connected to the positive electrode of the battery 9 and a source connected to the cathode of the diode 60. The anode of the diode 60 is connected to the negative electrode of the battery 9.
The diode 61 has a cathode connected to the positive electrode of the battery 9 and an anode connected to the drain of the switching element 55. The source of the switching element 55 is connected to the negative electrode of the battery 9.
The switching element 56 has a drain connected to the positive electrode of the battery 9 and a source connected to the cathode of the diode 62. The anode of the diode 62 is connected to the negative electrode of the battery 9.
The diode 63 has a cathode connected to the positive electrode of the battery 9 and an anode connected to the drain of the switching element 57. The source of the switching element 57 is connected to the negative electrode of the battery 9.

  That is, the switching element 52 and the diode 58 connected in series, the switching element 53 and the diode 59 connected in series, and the switching element 54 and the diode 60 connected in series are connected in series. The switching element 55 and the diode 61, the switching element 56 and the diode 62 connected in series, and the switching element 57 and the diode 63 connected in series are connected in parallel to the battery 9, respectively.

  A connection point between the switching element 52 and the diode 58 is connected to one end of a coil Lu of the SR motor 7, and a connection point between the switching element 53 and the diode 59 is connected to the other end of the coil Lu. One end of a coil Lv of the SR motor 7 is connected to a connection point between the switching element 54 and the diode 60, and the other end of the coil Lv is connected to a connection point between the switching element 55 and the diode 61. One end of a coil Lw of the SR motor 7 is connected to a connection point between the switching element 56 and the diode 62, and the other end of the coil Lw is connected to a connection point between the switching element 57 and the diode 63.

As described above, the drive circuit 12 is configured by the H-bridge circuit. Then, a control signal output from the control device 13 is input to the gates of the switching elements 52 to 57, and the switching elements 52 to 57 are switched on and off according to the input control signal. As a result, the current from the battery 9 is supplied to the coils Lu, Lv, and Lw of the SR motor 7.
The current sensor 20 detects a current flowing through each of the coils Lu, Lv, and Lw of the SR motor 7 and outputs the detected current to the control device 13.

  When switching the energizing phase of SR motor 7 from one phase to the other phase, control device 13 provides an overlap section in which both the one phase and the other phase are energized simultaneously. Then, the control device 13 gradually changes the current flowing in at least one of the one phase and the other phase in at least a part of the overlap section.

Hereinafter, the control device 13 in the present embodiment will be specifically described.
The control device 13 includes a current command value generation unit 132, a rotation direction command generation unit 133, a current detection unit 134, a position detection unit 135, a rotation speed detection unit 136, a command inclination width determination unit 137, and an advance angle / energization angle setting unit 138. , A current control unit 140, an energization timing output unit 141, a current command value correction unit 142, and a gate drive unit 143.

  The current command value generation unit 132 calculates a target value (hereinafter, “current command value”) of a current flowing through each of the coils Lu, Lv, and Lw of the SR motor 7 according to the accelerator signal output from the accelerator operation detection unit 5. get. Then, the current command value generation unit 132 outputs the obtained current command value to the command inclination width determination unit 137, the advance angle / conduction angle setting unit 138, and the current command value correction unit 142. For example, the current command value generation unit 132 includes a table in which the operation amount of the accelerator pedal 4 and the current command value are associated with each other, and calculates the operation amount of the accelerator pedal 4 indicated by the accelerator signal output from the accelerator operation detection unit 5. The current command value is calculated by acquiring the corresponding current command value from the table. Further, the current command value generation unit 132 may experimentally determine the current command value from the operation amount of the accelerator pedal 4 indicated by the accelerator signal output from the accelerator operation detection unit 5.

  The rotation direction command generator 133 acquires the rotation direction of the SR motor 7 based on the shift signal output from the shift position sensor 6. For example, when the current command value generation unit 132 determines that the shift position is the forward traveling position based on the shift signal output from the shift position sensor 6, it is determined that the rotation direction of the SR motor 7 is forward rotation. judge. Then, current command value generation section 132 outputs a rotation direction command signal indicating that the rotation direction of SR motor 7 is forward rotation to current command value correction section 142 and energization timing output section 141. On the other hand, when the current command value generation unit 132 determines that the shift position is the reverse traveling position based on the shift signal output from the shift position sensor 6, it is determined that the rotation direction of the SR motor 7 is reverse rotation. judge. Then, current command value generation section 132 outputs a rotation direction command signal indicating that the rotation direction of SR motor 7 is reverse rotation to current command value correction section 142 and energization timing output section 141.

  The current detection unit 134 detects a current value output from the current sensor 20 and flowing through each of the coils Lu, Lv, and Lw of the SR motor 7, and outputs the detected current value to the current control unit 140. For example, based on a detection signal of each phase current (winding current) output from each current sensor 20, a phase current being supplied to the SR motor 7 is detected, and a detected value of this phase current is output to the current control unit 140. I do.

The position detection unit 135 detects the rotation angle of the rotor 31 (the rotation position of the rotor 31) based on the signal output from the rotation angle sensor 8, and detects the rotation speed detection unit 136, the energization timing output unit 141, and the current command value. Output to the correction unit 142.
The rotation speed detection unit 136 detects a change amount per unit time of a signal indicating the rotation angle of the rotor 31 output from the position detection unit 135, and calculates the rotation speed (rotation speed) of the rotor 31 from the detected change amount. And outputs it to the command inclination width determination unit 137 and the advance angle / energization angle setting unit 138.

  The advancing / energizing angle setting unit 138 determines the advancing angle and the energizing angle in accordance with the current command value output from the current command value generating unit 132 and the rotation speed output from the rotation speed detecting unit 136, and outputs an energizing timing output unit. 141. The advance angle / energization angle setting unit 138 includes an advance angle map unit 138a and an energization angle map unit 138b.

  The advance angle map section 138a outputs the advance angle to the energization timing output section 141 based on the current command value output by the current command value generation section 132 and the rotation speed output by the rotation speed detection section 136. For example, the advance map unit 138a is a map in which the advance value is associated with each combination of the current command value and the rotation speed of the rotor 31. Here, the advance angle is determined by adjusting the energization start phase and energization end phase for each of the coils Lu, Lv, and Lw of each phase of the SR motor 7 to a predetermined position (for example, an increase start phase and a decrease phase of inductance) corresponding to a change in inductance of each phase. From the start phase, etc.). The advance angle tends to increase with an increase in the current command value and the number of revolutions. Note that, for example, the advance angle map unit 138a is set based on a simulation, a measurement result by an actual machine, or the like.

  The energization angle map unit 138b outputs the energization angle to the energization timing output unit 141 based on the current command value output by the current command value generation unit 132 and the rotation speed output by the rotation speed detection unit 136. For example, the energization angle map unit 138b is a map in which the value of the energization angle is associated with each combination of the current command value and the rotation speed of the rotor 31. Here, the energization angle is associated with each of the coils Lu, Lv, Lw of each phase of the SR motor 7. The energization angle map unit 138b is set based on a simulation, a measurement result by an actual machine, and the like.

  The energization timing output section 141 is currently energized based on the rotational position of the rotor 31 output from the position detection section 135 and the advance angle and energization angle output from the advance angle / energization angle setting section 138 ( The overlap section in which both the current energized phase coil and the next energized coil are energized simultaneously is determined in the rotation direction indicated by the rotation direction command signal. Then, the energization timing output section 141 outputs a timing signal indicating the determined overlap section to the gate drive section 143. For example, the calculation of the overlap section by the energization timing output unit 141 may be performed using the rotation speed and the energization angle map, or may be performed by an experiment.

  The command inclination width determination unit 137 determines the command value inclination width based on the current command value output from the current command value generation unit 132 and the rotation speed of the rotor 31 output from the rotation speed detection unit 136. The command value inclination width is a width (rotation angle of the rotor 31) that gradually changes the current flowing in at least one of the one phase and the other phase in at least a part of the overlap section. For example, the command inclination width determination unit 137 includes a table in which the current command value, the rotation speed of the rotor 31, and the command value inclination width are associated with each other, and a current command value output from the current command value generation unit 132, The command value inclination width corresponding to the rotation speed of the rotor 31 output from the rotation speed detection unit 136 is obtained from the table, thereby determining the command value inclination width. Further, the command value inclination width may be fixed, or may be changed according to the magnitude of the current command value or the rotation speed of the rotor 31.

  The command inclination width determination unit 137 outputs the determined command value inclination width to the current command value correction unit 142. In the overlap section, a section in which the current flowing in at least one of the one phase and the other phase is gradually changed may be referred to as an inclined energization section. This inclination energizing section may be determined based on the command value inclination width.

  The current control unit 140 gradually changes the current flowing in at least one of the one phase and the other phase in the rotation energization section in the rotation direction indicated by the rotation direction command signal.

  The current command value correction unit 142 acquires the current command value output from the current command value generation unit 132. The current command value correction unit 142 acquires the rotation position of the rotor 31 output from the position detection unit 135. The current command value correction unit 142 acquires the command value slope width output from the command slope width determination unit 137.

  The current command value correction unit 142 determines whether or not the rotation position of the rotor 31 output from the position detection unit 135 is in the inclined conduction section. When the rotational position of the rotor 31 is in the tilt energizing section, the current command value correction unit 142 performs correction for changing the current command value output from the current command value generation unit 132 with a predetermined slope. For example, the current command value correction unit 142 corrects the current command value of the phase in which the salient poles of the rotor 31 and the stator 32 are closer to the opposing position according to the rotation position of the rotor 31. Assuming that the corrected current command value is a current command correction value, the current command correction value is represented by, for example, the following equation.

  Current command correction value = current command value−current command value × (current rotation position of rotor 31 / command tilt width) (1)

  FIG. 3 is a diagram illustrating a process of correcting the current command value of the current command value correction unit 142 according to the first embodiment. As shown in FIG. 3, the current command value correction unit 142 supplies the current power to the current energized (current energized phase) coil and the next energized coil at the same time in the overlap section in which both coils are energized simultaneously. The current command value of the current flowing through the coil is corrected. For example, when the energized phase is switched from the V phase to the U phase in the inclined energized interval of the overlap interval in which the V-phase coil Lv and the U-phase coil Lu are energized simultaneously, the current command value correction unit 142 A correction for reducing the current command value of the V-phase coil Lv is performed.

  When the energized phase is switched from the U phase to the W phase in the inclined energized section of the overlap section in which the U-phase coil Lu and the W-phase coil Lw are energized simultaneously, the current command value correction unit 142 Correction for reducing the current command value of the U-phase coil Lu is performed. When the energized phase is switched from the W phase to the V phase in the inclined energized section of the overlap section in which the W-phase coil Lw and the V-phase coil Lv are energized at the same time, the current command value correction unit 142 Is performed to reduce the current command value of the coil Lw. Note that, in the example illustrated in FIG. 3, a case will be described in which the overlap section is an inclined energization section, but the present invention is not limited to this. That is, it is sufficient that at least a part of the overlap section includes the inclined energization section. For example, when switching the energized phase from one phase to the other phase, the current command value correction unit 142 sets the rotor 31 of the SR motor 7 from the timing at which the current flows through the other phase (the timing at which the overlap section starts). After rotating by a predetermined angle, the current command value of the current flowing in one phase may be gradually reduced. Note that the predetermined angle is 0 degree or more.

The current command value correction unit 142 outputs the current command value output from the current command value generation unit 132 to the current control unit 140 when the rotational position of the rotor 31 is not in the tilt energizing section.
When the rotational position of rotor 31 is in the inclined energizing section, current command value correction section 142 outputs a current command correction value, which is a corrected current command value, to current control section 140 as a new current command value.

The current control unit 140 includes a current difference calculation unit 1411 and a PWM output unit 1412.
The PWM output unit 1412 performs PWM (Pulse Width Modulation) control of a phase current supplied to the SR motor 7. The current difference calculation unit 1411 calculates a deviation between the current command value supplied from the current command value correction unit 142 and the current detection value supplied from the current detection unit 134 (hereinafter, referred to as “current difference value”). The current control unit 140 outputs the calculated current difference value to the PWM output unit 1412.

  The PWM output unit 1412 determines the duty ratio of the switching elements 52 to 57 so that the current difference value decreases. The PWM output unit 1412 outputs the calculated duty ratio to the gate driving unit 143. Here, the PWM output unit 1412 may calculate the above-described duty ratio using generally known PI (Proportional Integral Derivative) control or PID (Proportional Integral Derivative) control based on the current difference value. Good.

  The gate drive unit 143 turns on or off the switching elements 52 to 57 included in the drive circuit 12 based on the timing signal output from the energization timing output unit 141 and the duty ratio output from the PWM output unit 1412. Is output to the gates of the switching elements 52 to 57.

  Hereinafter, a flow of a process of correcting the current command value of the control device 13 in the first embodiment will be described. FIG. 4 is a diagram illustrating a flow of a process of correcting the current command value of the control device 13 according to the first embodiment.

  The current command value generator 132 acquires a current command value of a current flowing through each of the coils Lu, Lv, Lw of the SR motor 7 according to the accelerator signal output from the accelerator operation detector 5 (Step S101). The current command value generator 132 outputs the obtained current command value to the current command value corrector 142 and the command slope width determiner 137.

  The rotation direction command generator 133 acquires the rotation direction of the SR motor 7 based on the shift signal output from the shift position sensor 6 (Step S102). The current command value generation unit 132 outputs a rotation direction command signal indicating the acquired rotation direction of the SR motor 7 to the current command value correction unit 142.

  The position detection unit 135 acquires the rotation angle of the rotor 31 (the rotation position of the rotor 31) based on the signal output from the rotation angle sensor 8, and outputs the rotation angle to the rotation speed detection unit 136 and the current command value correction unit 142. (Step S103).

  The command inclination width determination unit 137 determines the command value inclination width based on the current command value output from the current command value generation unit 132 and the rotation speed of the rotor 31 output from the rotation speed detection unit 136 ( Step S104). The command inclination width determination unit 137 outputs the determined command value inclination width to the current command value correction unit 142.

  The current command value correction unit 142 determines whether or not the rotation position of the rotor 31 output from the position detection unit 135 is in the inclined energizing section (Step S105). The current command value correction unit 142 corrects the current command value output from the current command value generation unit 132 when the rotation position of the rotor 31 is in the inclined energizing section. For example, the current command value correction unit 142 corrects the current command value of the phase in which the salient poles of the rotor 31 and the stator 32 are closer to the facing position according to the rotational position of the rotor 31 using Expression (1) ( Step S106). The current command value correction unit 142 outputs the current command value output from the current command value generation unit 132 to the current control unit 140 when the rotational position of the rotor 31 is not in the tilt energizing section.

  As described above, the motor control device 1 according to the first embodiment is configured such that when the energized phase is switched from one phase to the other phase, the overlap section energizes both the one phase and the other phase. And the current flowing in at least one of the one phase and the other phase is gradually changed in at least a part of the overlap section of the current supply timing output section. As a result, it is possible to reduce a torque change occurring in the overlap section. For example, in the case where the energized phase is switched from one phase to the other phase, and in the two-phase simultaneous energization of one phase and the other phase, the current command value of the coil of one phase is inclined to be sharp. A large torque change. Further, in the conventional motor control device, since the energization of the one phase coil is stopped, the force generated in the radial direction with respect to the stator 32 is suddenly released, and the stator 32 vibrates. Therefore, the operation noise of the stator 32 was generated by the vibration. The motor control device 1 of the present embodiment alleviates a steep torque change by inclining the current command value of the one-phase coil. Therefore, the force generated in the radial direction of the stator 32 is gradually released, so that the vibration of the stator 32 is reduced. Therefore, the operation sound of the stator 32 is reduced.

(Second embodiment)
Hereinafter, a motor control device 1A according to the second embodiment will be described with reference to the drawings. In the second embodiment, when switching from one phase to the other phase, the current flowing in the other phase is gradually increased, and after the current value flowing in the other phase reaches the threshold value, the SR motor 7 , The current flowing in one phase is gradually reduced.

FIG. 5 is a configuration diagram of an electric vehicle system 100A to which the motor control device 1A according to the second embodiment is applied.
An electric vehicle system 100A according to the second embodiment includes a motor control device 1A, an accelerator pedal 4, an accelerator operation detection unit 5, a shift position sensor 6, an SR motor 7, a rotation angle sensor 8, and a battery 9.

FIG. 6 is a diagram illustrating an example of a schematic configuration of a motor control device 1A according to the second embodiment. As shown in FIG. 6, the motor control device 1A according to the first embodiment includes a drive circuit 12 and a control device 13A.
The control device 13A includes a current command value generation unit 132, a rotation direction command generation unit 133, a current detection unit 134, a position detection unit 135, a rotation speed detection unit 136, a command inclination width determination unit 137, a lead angle / conduction angle setting unit 138. , A current control unit 140A, an energization timing output unit 141, a current command value correction unit 142A, and a gate drive unit 143.

  When switching from one phase to the other phase, current control unit 140A gradually increases the current flowing to the other phase, and sets the SR motor 7 to a predetermined value after the current value flowing to the other phase reaches a threshold value. After rotating by an angle, the current flowing in one phase is gradually reduced.

  The current command value corrector 142A has the same function as the current command value corrector 142 in the overlap section, and also has the function of correcting the current command value of the current flowing in the other phase. In the following description, one phase is defined as a V phase and the other phase is defined as a U phase.

  The current command value correction unit 142A acquires the current command value output from the current command value generation unit 132. The current command value correction unit 142A acquires the rotation position of the rotor 31 output from the position detection unit 135. The current command value correction unit 142A acquires the command value inclination width output from the command inclination width determination unit 137.

  The current command value correction unit 142A determines whether or not the rotation position of the rotor 31 output from the position detection unit 135 is in the inclined energizing section. When the rotational position of the rotor 31 is in the gradient energizing section, the current command value correction unit 142A performs correction for changing the current command value output from the current command value generation unit 132 with a predetermined slope.

FIG. 7 is a diagram illustrating a process of correcting a current command value of the current command value correction unit 142A according to the second embodiment.
As shown in FIG. 7, the current command value correction unit 142 </ b> A controls the coil in the overlap section in which both the V-phase coil Lv that is currently energized and the U-phase coil Lu that is energized next are energized simultaneously. The current command value of the current flowing through Lu and the coil Lv is corrected. For example, in the inclined energizing section of the overlap section in which the V-phase coil Lv and the U-phase coil Lu are simultaneously energized, the current command value correction section 142A gradually reduces the current command value of the coil Lu from the start of the overlap section. To increase. As a result, it is possible to reduce a steep change in torque that occurs when the coil Lu is energized.

  Further, the current command value correction unit 142A gradually reduces the current flowing through the coil Lv after the SR motor 7 rotates by a predetermined angle (0 degree or more) after the current value flowing through the coil Lu reaches the threshold value. Decrease. Thus, it is possible to reduce a sharp change in torque of the SR motor 7 that occurs when the energization of the coil Lv is stopped. Note that, in the example illustrated in FIG. 7, a case will be described where the overlap section is an inclined energization section, but the present invention is not limited to this. That is, it is sufficient that at least a part of the overlap section includes the inclined energization section.

  As described above, when switching from one phase to the other phase, the motor control device 1A in the second embodiment gradually increases the current flowing in the other phase and sets the current value flowing in the other phase to the threshold value. , After the SR motor 7 rotates by a predetermined angle, the current flowing in one phase is gradually reduced. Accordingly, the same effect as that of the first embodiment can be obtained, and a sharp change in torque that occurs when a current flows through the other phase can be reduced.

  In the above-described embodiment, as shown in FIG. 8, the current control units 140 and 140A simultaneously change the ON state or the OFF state of both the low-side switching element and the high-side switching element of the drive circuit 12 by the PWM in the overlap period. It may be controlled. For example, as a conventional method, there is a method in which only the high-side switching element is subjected to PWM control. However, in this method, since a path through which the current flows through the coil is formed, the actual phase current value may not follow the current command value due to the influence of the inductance of the coil. Therefore, in such a case, the PWM control of both the high-side switching element and the low-side switching element at the same time improves the followability of the phase current value actually flowing through the coil with respect to the current command value. For example, in the second embodiment, the current control unit 140A simultaneously performs PWM control on both the high-side switching element and the low-side switching element in the inclined conduction section in which the current flowing through the coil Lv is gradually reduced. Thus, the follow-up of the phase current to the current command value can be improved.

  In the above-described embodiment, the diodes 58 to 63 may be replaced by switching elements such as IGBT, FET, and BJT.

  Each unit of the motor control device 1 may be realized by hardware, may be realized by software, or may be realized by a combination of hardware and software. The computer may function as a part of the motor control device 1 by executing the program. The program may be stored on a computer-readable medium, or may be stored on a storage device connected to a network.

  The control device 13 in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read and executed by a computer system. Here, the “computer system” includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, and a CD-ROM, and a storage device such as a hard disk built in a computer system. Further, the “computer-readable recording medium” refers to a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, which dynamically holds the program for a short time. Such a program may include a program that holds a program for a certain period of time, such as a volatile memory in a computer system serving as a server or a client in that case. The program may be for realizing a part of the functions described above, or may be a program that can realize the functions described above in combination with a program already recorded in a computer system, It may be realized using a programmable logic device such as an FPGA (Field Programmable Gate Array).

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to the embodiments, and includes a design and the like within a range not departing from the gist of the present invention.

  The order of execution of processes such as operations, procedures, steps, and steps in the devices, systems, programs, and methods shown in the claims, the description, and the drawings is particularly “before” or “before”. It should be noted that the output can be realized in any order as long as the output of the previous process is not used in the subsequent process. Regarding the operation flow in the claims, the specification, and the drawings, even if it is described using “first,” “second,” or the like for convenience, it means that it is essential to implement in this order. Not something.

Reference Signs List 1 motor control device 7 SR motor 8 rotation angle sensor 132 current command value generation unit 133 rotation direction command generation unit 134 current detection unit 135 position detection unit 136 rotation speed detection unit 137 command inclination width determination unit 138 advance angle and conduction angle setting unit 140 Current control unit 142 Current command value correction unit 141 Energization timing output unit 143 Gate drive unit

Claims (4)

A motor control device that rotationally drives the SR motor by switching energization of a coil corresponding to each phase of a polyphase SR motor,
When switching the energized phase from one phase to the other phase, an energization timing output unit that provides an overlap section for energizing both the one phase and the other phase,
A position detection unit that detects a rotation position of the rotor of the SR motor;
A rotation speed detection unit that detects a rotation speed of the rotor based on the rotation position detected by the position detection unit,
A current control unit that gradually changes a current flowing in at least one of the one phase and the other phase in the inclined energization section that is at least a part of the overlap section,
A current command value generation unit that generates a current command value that is a target value of a current flowing in each phase according to an accelerator signal indicating an accelerator operation amount;
A command indicating a width of a rotation position of the rotor, which gradually changes the current based on the current command value generated by the current command value generation unit and the rotation speed detected by the rotation speed detection unit. A command slope width determining unit for determining a value slope width,
The current command value of the overlap section, a current command value correction unit that corrects using the current rotation position and the command value inclination width detected by the position detection unit,
Has,
The current control unit controls the current flowing through each of the phases based on the current command value corrected by the current command value correction unit in the inclined energizing section, so that the one phase and the other phase are controlled. Gradually change the current flowing in at least one of the phases
A motor control device characterized by the above-mentioned .   2. The motor control according to claim 1, wherein the current control unit gradually reduces the current flowing in the one phase after the SR motor rotates by a predetermined angle from the timing of flowing the current in the other phase. 3. apparatus.   The current control unit gradually increases the current flowing to the other phase, and after the SR motor rotates by a predetermined angle after the current value flowing to the other phase reaches a threshold value, The motor control device according to claim 1, wherein the current flowing through the motor is gradually reduced. The motor control device according to any one of claims 1 to 3,
Further comprising a low-side switching element and a high-side switching element connected to the coil,
The current-control unit, in the overlap interval, the simultaneous PWM control to makes the chromophore at the distal end over motor controller both on or off state of the low side switching element and the high-side switching element.

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