JP2005237054A - Motor drive unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor drive unit that can precisely reduce a torque ripple. <P>SOLUTION: In a control device 80, an angle correction part 82 holds the relationship between torque of which the torque ripple is minimum and a current lead angle, and corrects a sensor value θ from a rotation position sensor 70 by extracting the current lead angle α that corresponds to a torque command value TR output from an external ECU. Each of a three-phase/two-phase converter 83, a current command generation part 84, subtractors 85, 86, a PI control part 87, a two-phase/three-phase converter 88, and a PWM generation part 89 generates a signal PWM by using a correction value θ+α that is corrected by the angle correction part 82, and outputs it to an inverter 40. The inverter 40 drives a motor generator 60 by the signal PWM, whereby the motor drive unit 100 drives the motor generator 60 so that the torque ripple becomes minimum. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a motor drive device that drives a motor generator so as to reduce noise.

  Conventionally, the motor generator is driven so that its efficiency is the highest. Specifically, the motor generator is driven so that the torque / current obtained by dividing the torque generated by the motor generator by the current flowing through the motor generator is maximized.

  However, the motor generator driving method giving priority to such efficiency has a problem that noise generated by the motor generator increases. One cause of noise generated by this motor generator is an increase in torque ripple. Therefore, one way to reduce the noise generated by the motor generator is to reduce torque ripple.

Patent Document 1 discloses a method for reducing torque ripple. In view of the fact that the frequency of the AC component of the output torque is an integral multiple of the basic excitation frequency of the motor generator, this method adds a series of harmonic currents to the basic rectangular current to counteract the unprocessed torque ripple. And the torque ripple is reduced by the generated torque component (Patent Document 1).
Japanese Patent Laid-Open No. 2002-119096 JP 2000-152697 A Japanese Patent Laid-Open No. 2002-374691

  However, the conventional method of reducing torque ripple reduces torque ripple due to the torque component generated by a series of harmonic currents added to the basic rectangular current, so the torque ripple is accurately reduced when the phase of the basic rectangular current is shifted. There is a problem that you can not.

  Accordingly, the present invention has been made to solve such a problem, and an object thereof is to provide a motor drive device capable of accurately reducing torque ripple.

  Another object of the present invention is to provide a motor drive device capable of accurately reducing torque ripple when noise reduction is required.

  Furthermore, another object of the present invention is to provide a motor drive device capable of accurately reducing torque ripple according to the operation mode of the motor generator.

  According to the present invention, the motor driving device includes the phase angle determining means and the control means. The phase angle determining means sets a suitable current phase angle for flowing a current to the motor generator so that a torque ripple indicating a fluctuation rate of the actually output torque with respect to the average value of the torque output by the motor generator is equal to or less than a predetermined value. A phase angle determination process is performed. The control means drives and controls the motor generator using the suitable current phase angle determined by the phase angle determination means.

  Preferably, the phase angle determining means holds a map indicating a relationship between the torque and the current phase angle when the torque ripple becomes a predetermined value or less, and the current phase angle corresponding to the input torque command value is determined from the map. Extract and determine a suitable current phase angle.

  Preferably, the phase angle determination means performs the phase angle determination process when the rotation speed of the motor generator is within a predetermined range in the regeneration mode of the motor generator.

  Preferably, the phase angle determining means performs the phase angle determining process when noise below the reference value is required in the power running mode of the motor generator.

  According to the invention, the motor driving device includes the phase angle determining means and the control means. In the first operation mode, the phase angle determination means causes a current to flow through the motor generator so that a torque ripple representing a fluctuation rate of the actually output torque with respect to the average value of the torque output from the motor generator is equal to or less than a predetermined value. In the second operation mode other than the first operation mode, the current is supplied to the motor generator so that the current flowing through the motor generator is minimized. A second phase angle determination process for determining a second current phase angle for flow is performed. The control means drives and controls the motor generator using the first current phase angle or the second current phase angle determined by the phase angle determination means.

  Preferably, the phase angle determining means includes a first map showing a relationship between the torque and the current phase angle when the torque ripple becomes a predetermined value or less, and a torque and current phase angle when the current flowing through the motor generator is minimized. And a second map showing the relationship between the current phase angle and the current phase angle corresponding to the torque command value input in the first operation mode is extracted from the first map to obtain the first current phase angle. The current phase angle corresponding to the torque command value input in the second operation mode is extracted from the second map to determine the second current phase angle.

  Preferably, the first operation mode is a mode in which the hybrid vehicle travels only by the torque generated by the motor generator. The second operation mode is a mode in which the hybrid vehicle travels with torque generated by the motor generator and the internal combustion engine.

  Preferably, the first operation mode is a mode in which the electric vehicle travels other than acceleration travel. The second operation mode is a mode in which the electric vehicle performs acceleration traveling.

  Preferably, the phase angle determination means performs the first phase angle determination process when the rotation speed of the motor generator is within a predetermined range in the regeneration mode of the motor generator.

  Preferably, the predetermined value is a minimum value of torque ripple.

  The motor drive device according to the present invention controls the current phase angle to a suitable current phase angle for flowing current to the motor generator so that the torque ripple is equal to or less than a predetermined value, and drives the motor generator using the suitable current phase angle. To do.

  Therefore, according to the present invention, torque ripple can be accurately reduced. As a result, noise and / or vibration generated by the motor generator can be reduced.

  Further, the motor drive device according to the present invention controls the current phase angle to a suitable current phase angle for flowing current to the motor generator so that the torque ripple is a predetermined value or less when noise reduction is required, The motor generator is driven using a suitable current phase angle.

  Therefore, according to the present invention, when noise reduction is required, the noise generated by the motor generator can be reduced.

  Further, in the first operation mode, the motor drive device according to the present invention controls the current phase angle to the first current phase angle for flowing current to the motor generator so that the torque ripple is not more than a predetermined value. The motor generator is driven using a current phase angle of 1. Then, in the second operation mode, the motor drive device controls the current phase angle to a second current phase angle for flowing current to the motor generator so that the current flowing to the motor generator is minimized, and the second The motor generator is driven using the current phase angle.

  Therefore, according to the present invention, the torque ripple can be accurately reduced according to the operation mode. As a result, noise and / or vibration generated by the motor generator can be accurately reduced in a predetermined operation mode.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a schematic block diagram of a motor drive device according to Embodiment 1 of the present invention. Referring to FIG. 1, motor drive device 100 according to Embodiment 1 includes DC power supply 10, voltage sensor 12, capacitor 30, inverter 40, current sensor 50, rotational position sensor 70, and control device 80. With.

  DC power supply 10 is connected between power supply line 1 and earth line 2. Capacitor 30 is connected in parallel to DC power supply 10 between power supply line 1 and ground line 2. The voltage sensor 12 detects the voltage Vm across the capacitor 30 and outputs it to the control device 80.

  Inverter 40 receives a DC voltage via capacitor 30 and converts the received DC voltage into an AC voltage by signal PWM from control device 80 to drive motor generator 60.

  Current sensor 50 detects motor currents Iu and Iv flowing through motor generator 60 and outputs the detected motor currents Iu and Iv to control device 80. In FIG. 1, only two current sensors 50 are shown. When the motor generator 60 is a three-phase motor, if the motor currents Iu and Iv flowing in the two phases are detected, the motor current Iw flowing in the remaining phases is calculated based on the detected motor currents Iu and Iv. Because it can. Therefore, when the motor currents Iu, Iv, and Iw flowing in each of the three phases are detected independently, three current sensors 50 may be provided.

  Motor generator 60 is a three-phase motor including a U-phase coil, a V-phase coil, and a W-phase coil as stator coils.

  The rotational position sensor 70 detects the rotational position of the rotor of the motor generator 60 and outputs a sensor value θ indicating the detected rotational position to the control device 80.

  The control device 80 includes a rotation speed detection unit 81, an angle correction unit 82, a three-phase / two-phase conversion unit 83, a current command generation unit 84, subtracters 85 and 86, a PI control unit 87, and a two-phase control unit. A / 3-phase converter 88 and a PWM generator 89 are included.

  The rotational speed detection unit 81 receives the sensor value θ from the rotational position sensor 70 and detects the motor rotational speed MRN based on the received sensor value θ. Then, rotation speed detection unit 81 outputs motor rotation number MRN to angle correction unit 82 and current command calculation unit 84.

  The angle correction unit 82 corrects the sensor value θ from the rotation 1 sensor 70 by a method described later, and outputs the corrected correction value θ + α to the three-phase / two-phase conversion unit 83 and the two-phase / three-phase conversion unit 88. .

  Three-phase / two-phase converter 83 receives motor currents Iu and Iv from two current sensors 50 and 50, respectively. Then, the three-phase / two-phase converter 83 calculates a motor current Iw = −Iu−Iv based on the motor currents Iu and Iv.

  Then, the three-phase / two-phase conversion unit 83 converts the motor currents Iu, Iv, and Iw into three-phase to two-phase using the correction value θ + α from the angle correction unit 82. That is, the three-phase / two-phase conversion unit 83 calculates the current values Id, Iq by substituting the motor currents Iu, Iv, Iw and the correction value θ + α into the following equation.

  That is, the three-phase / two-phase conversion unit 83 uses the correction values θ + α for the three-phase motor currents Iu, Iv, Iw flowing in the respective phases of the three-phase coil of the motor generator 60, and the current values flowing in the d-axis and the q-axis. Convert to Id, Iq. Then, the three-phase / two-phase conversion unit 83 outputs the calculated current value Id to the subtractor 85 and outputs the calculated current value Iq to the subtractor 86.

  The current command generation unit 84 receives a torque command value TR from an ECU (Electrical Control Unit) provided outside the motor drive device 100, receives a motor rotation number MRN from the rotation number detection unit 81, and receives a voltage Vm from the voltage sensor 12. Receive. The current command generator 84 generates current commands Id * and Iq * for outputting the torque specified by the torque command value TR based on the torque command value TR, the motor rotational speed MRN, and the voltage Vm. The generated current command Id * is output to the subtractor 85, and the generated current command Iq * is output to the subtractor 86.

  The subtracter 85 calculates a deviation ΔId between the current command Id * and the current value Id, and outputs the calculated deviation ΔId to the PI control unit 87. Subtractor 86 calculates deviation ΔIq between current command Iq * and current value Iq, and outputs the calculated deviation ΔIq to PI control unit 87.

  The PI control unit 87 calculates the voltage operation amounts Vd and Vq for adjusting the motor current using the PI gain with respect to the deviations ΔId and ΔIq, and the calculated voltage operation amounts Vd and Vq are two-phase / three-phase conversion units. Output to 88.

  The two-phase / three-phase conversion unit 88 performs two-phase three-phase conversion on the voltage operation amounts Vd and Vq from the PI control unit 87 using the correction value θ + α from the angle correction unit 82. That is, the two-phase / three-phase converter 88 substitutes the voltage manipulated variables Vd and Vq from the PI controller 87 and the correction value θ + α from the angle corrector 82 into the following equation and applies them to the three-phase coil of the motor generator 60. The voltage operation amounts Vu, Vv, Vw to be calculated are calculated.

  That is, the two-phase / three-phase converter 88 applies the voltage operation amounts Vd, Vq applied to the d-axis and the q-axis to the voltage operation amounts Vu, Vv, Vq applied to the three-phase coil of the motor generator 60 using the correction value θ + α. Convert to Vw.

  Then, the two-phase / three-phase converter 88 outputs the voltage manipulated variables Vu, Vv, and Vw to the PWM generator 89.

  The PWM generator 89 generates a signal PWM based on the voltage manipulated variables Vu, Vv, Vw and the voltage Vm from the voltage sensor 12, and outputs the generated signal PWM to the inverter 40. More specifically, the PWM generation unit 89 sets the height and width of the signal PWM according to the voltage level of the voltage Vm, and generates the signal PWM. In this case, when the voltage level of the voltage Vm becomes relatively high, the PWM generation unit 89 generates the signal PWM with a relatively high height of the signal PWM and a relatively narrow width, and the voltage Vm When the voltage level of the signal PWM becomes relatively low, the signal PWM is generated with the signal PWM having a relatively low height and a relatively wide width.

  FIG. 2 is a circuit diagram of inverter 40 shown in FIG. Referring to FIG. 2, inverter 40 includes a U-phase arm 15, a V-phase arm 16, and a W-phase arm 17. U-phase arm 15, V-phase arm 16 and W-phase arm 17 are connected in parallel between power supply line 1 and earth line 2.

  The U-phase arm 15 includes NPN transistors Q1 and Q2 connected in series, the V-phase arm 16 includes NPN transistors Q3 and Q4 connected in series, and the W-phase arm 17 includes NPN transistors connected in series. It consists of transistors Q5 and Q6. In addition, diodes D1 to D6 that flow current from the emitter side to the collector side are connected between the collectors and emitters of the NPN transistors Q1 to Q6, respectively.

  An intermediate point of each phase arm of inverter 40 is connected to each phase end of each phase coil of motor generator 60. That is, the other end of the U-phase coil of motor generator 60 is at the intermediate point of NPN transistors Q1 and Q2, the other end of the V-phase coil is at the intermediate point of NPN transistors Q3 and Q4, and the other end of the W-phase coil is NPN transistor Q5. , Q6, respectively.

  FIG. 3 is a relationship diagram between torque and current advance angle. In FIG. 3, the vertical axis represents torque and the horizontal axis represents current advance angle. It should be noted that the current advance angle is determined by motor generator 60 how much the timing at which an alternating current is supplied to each phase coil constituting the stator magnetic pole is earlier than the timing at which each rotor magnetic pole of the rotor is closest to each stator magnetic pole of the stator. Is an electrical angle, i.e., a phase angle.

  Referring to FIG. 3, curve k1 shows the relationship between torque and current advance angle when the current flowing through each phase coil of motor generator 60 is used as a parameter. A curve k2 shows the relationship between the torque and the current advance angle when the torque ripple is minimized. Further, curve k3 shows the relationship between the torque and the current advance angle when the torque / current obtained by dividing the torque generated by motor generator 60 by the current flowing through motor generator 60 is maximum.

  In the present invention, “torque ripple” refers to the rate of fluctuation of the torque actually output with respect to the average value of the torque output by motor generator 60.

  Each current flowing through motor generator 60 is greatly affected by the current advance angle as it increases (see curve k1). Therefore, when the motor generator 60 is to output a large torque, it is necessary to accurately control the current advance angle.

  FIG. 4 is a relationship diagram between torque ripple and torque. In FIG. 4, the vertical axis represents torque ripple, and the horizontal axis represents torque. Also, various figures such as circles, triangles, and squares in FIG. 4 represent current advance angles that are parameters. Referring to FIG. 4, at each current advance angle, the torque ripple decreases rapidly as the torque increases, and then maintains a substantially constant value. In each torque, torque ripple is minimized for a predetermined current advance angle. For example, at a torque of 50 [Nm], the torque ripple changes in a range of about 15 to 30% with respect to the current advance angle, and becomes minimum at a current advance angle of around 0 degrees.

  Therefore, the curve k2 shown in FIG. 3 is obtained by extracting the current advance angle at which the torque ripple is minimized for each torque from FIG. 4 and plotting the relationship between the extracted current advance angle and the torque.

  FIG. 5 is a relationship diagram between current and torque. In FIG. 5, the vertical axis represents current, and the horizontal axis represents torque. Further, various figures such as circles, triangles, and squares in FIG. 5 represent current advance angles that are parameters. Referring to FIG. 5, at each current advance angle, the torque is approximately proportional to the current. Further, at each torque, the current is minimum for a predetermined current advance angle. For example, at a torque of 100 [Nm], the current changes in a range of about 120 to 240 [Arms] with respect to the current advance angle, and becomes minimum at a current advance angle of about 30 degrees.

  Therefore, the curve k3 shown in FIG. 3 is obtained by extracting the current advance angle at which the current is minimized at each torque from FIG. 5 and plotting the relationship between the extracted current advance angle and the torque.

  In the above description, it has been described that the curve k3 in FIG. 3 shows the relationship between the torque and the current advance angle when the torque / current is maximized. Therefore, the current advance angle at which the current is minimized at each torque is extracted from FIG. 5, and the relationship between the extracted current advance angle and the torque is equal to the curve k3 in FIG.

  Referring again to FIG. 3, in normal motor control, the current advance angle at each torque is determined according to curve k3 so that the efficiency of motor generator 60 is the best, and the motor using the determined current advance angle. The generator 60 is driven.

  However, in the motor driving method giving priority to such efficiency, the torque ripple increases and the noise generated by the motor generator 60 increases.

  Therefore, in the first embodiment, the current advance angle is determined for each torque in accordance with curve k2, and motor generator 60 is driven using the determined current advance angle.

  Again referring to FIG. 1, angle correction unit 82 holds curve k2 shown in FIG. 3 as a map. Then, angle correction unit 82 receives torque command value TR from the external ECU, and extracts current advance angle α corresponding to the received torque command value TR from the map (curve k2). Then, the angle correction unit 82 adds the extracted current advance angle α to the sensor value θ from the rotational position sensor 70 to correct the sensor value θ to the correction value θ + α, and the corrected correction value θ + α is three-phase / 2. Output to phase conversion unit 83 and 2-phase / 3-phase conversion unit 88.

  Then, the three-phase / two-phase conversion unit 83 converts the three-phase currents Iu, Iv, Iw into the two-phase currents Id, Iq using the correction value θ + α. Then, the current command generator 84 generates current commands Id * and Iq * by the method described above and outputs them to the subtracters 85 and 86, respectively. The subtracter 85 subtracts the current Id from the current command Id * and outputs a deviation ΔId to the PI control unit 87, and the subtracter 86 subtracts the current Iq from the current command Iq * to obtain the deviation ΔIq as the PI control unit 87. Output to.

  Then, the PI control unit 87 calculates the voltage operation amounts Vd and Vq based on the deviations ΔId and ΔIq by the method described above, and outputs the calculated voltage operation amounts Vd and Vq to the two-phase / three-phase conversion unit 88. . The two-phase / three-phase converter 88 converts the voltage manipulated variables Vd and Vq into the voltage manipulated variables Vu, Vv, and Vw using the correction value θ + α, and outputs the voltage manipulated variables Vu, Vv, and Vw to the PWM generator 89. The PWM generator 89 generates a signal PWM based on the voltage manipulated variables Vu, Vv, and Vw by the method described above, and outputs the signal PWM to the inverter 40.

  That is, the three-phase / two-phase conversion unit 83, the current command generation unit 84, the subtractors 85 and 86, the PI control unit 87, the two-phase / three-phase conversion unit 88, and the PWM generation unit 89 use the correction value θ + α to generate a signal. PWM is generated and output to the inverter 40.

  Inverter 40 drives motor generator 60 by passing a current through each phase coil of motor generator 60 so that torque ripple generated in motor generator 60 is minimized.

  As a result, the current flowing through each phase coil of motor generator 60 is controlled in consideration of the current advance angle, so that torque ripple can be accurately reduced.

  FIG. 6 is a conceptual diagram for measuring noise and vibration in motor generator 60. 6A is a side view of the motor generator 60, and FIG. 6B is a plan view of the motor generator 60 viewed from the direction A shown in FIG. 6A.

  6A and 6B, a face plate 61 is attached to one end in the Z-axis direction. The vibration pick 62 is attached to the other end of the motor generator 60 on the opposite side of the face plate 61 in the Z-axis direction. Further, the microphone 63 is disposed on the upper side of the motor generator 60 in the approximate center of the motor generator 60 in the Z-axis direction.

  Then, the torque output by the motor generator 60 is kept constant at 30 [Nm], and the vibration and noise generated by the motor generator 60 by the vibration pick 62 and the microphone 63 are changed by changing the rotation speed in the range of 1000 to 8000 rpm. It was measured. The vibration pick 62 detects vibrations in the X-axis direction, the Y-axis direction, and the Z-axis direction.

  FIG. 7 is a diagram showing the vibration-rotational speed relationship and the sound-rotational speed relationship measured under the conditions described in FIG. In (a), (b) and (c) of FIG. 7, the vertical axis represents vibration and the horizontal axis represents the number of rotations. In FIG. 7D, the vertical axis represents sound (noise), and the horizontal axis represents the rotational speed. Further, the curves k4, k6, k8, and k10 are obtained when the current advance angle is determined so as to minimize the torque ripple according to the curve k2 shown in FIG. 3, and the motor generator 60 is driven using the determined current advance angle. Curves k5, k7, k9, and k11 show a case where the current advance angle is determined so as to minimize the current according to the curve k3 shown in FIG. 3, and the motor generator 60 is driven using the determined current advance angle. Show.

  Referring to FIG. 7, the vibration in the X-axis direction becomes smaller when motor generator 60 is driven so that torque ripple is minimized in a region where the rotational speed is high. Further, the vibration in the Y-axis direction and the Z-axis direction is slightly smaller when the motor generator 60 is driven so that the torque ripple is minimized (see FIGS. 7A to 7C).

  Further, the sound (noise) is smaller when the motor generator 60 is driven so that the torque ripple is minimized in the entire rotation speed range.

  Therefore, noise and vibration can be reduced by driving the motor generator 60 so that the torque ripple is minimized.

  FIG. 8 is a relationship diagram between the motor regenerative sound and the distribution of the braking force and the rotational speed of the motor. In FIG. 8, the horizontal axis represents the rotational speed of the motor, and the vertical axis represents the distribution of the motor regenerative sound and the braking force.

  Referring to FIG. 8, a region RGE1 above the straight line LN1 indicates a braking force by the hydraulic brake, and a region RGE2 below the straight line LN1 indicates the braking force by regeneration. Thus, the overall braking force is determined by the sum of the braking force by the hydraulic brake and the braking force by regeneration.

  A curve k12 shows the relationship between the motor regenerative sound and the rotation speed of the motor when the motor generator 60 is driven so that the current is minimized. A curve k13 shows the relationship between the motor regenerative sound and the motor rotation speed when the motor generator 60 is driven so that the torque ripple is minimized when the motor rotation speed is in the range of MRS1 to MRS2.

  When the rotational speed of the motor is in the range of MRS1 to MRS2, the regenerative sound of the motor suddenly increases. In this rotational speed range, the angle correction unit 82 sets the current advance angle α so that the torque ripple is minimized. Then, the motor driving apparatus 100 drives the motor generator 60 so that the torque ripple is minimized.

  As a result, the regenerative sound of the motor can be greatly reduced when the rotational speed is in the range of MRS1 to MRS2 as indicated by the curve k13.

  Therefore, in the regenerative mode of motor generator 60, angle correction unit 82 receives motor rotation number MRN from rotation number detection unit 81 and calculates rotation speed MRS based on the received motor rotation number MRN. Then, when the calculated rotation speed MRS is in the range of the rotation speeds MRS1 to MRS2 shown in FIG. 8, the angle correction unit 82 determines the current advance angle so that the torque ripple is minimized according to the curve k2 shown in FIG. It may be.

  In angle correction unit 82, whether motor generator 60 is in the regeneration mode is determined based on torque command value TR and motor rotational speed MRN. That is, when the relationship between the motor rotation speed MRN and the torque command value TR exists in the first quadrant or the second quadrant in the orthogonal coordinates with the motor rotation speed on the horizontal axis and the torque command value on the vertical axis, the motor generator 60 is in the power running mode, and when the relationship between the motor rotational speed MRN and the torque command value TR exists in the third quadrant or the fourth quadrant, the motor generator 60 is in the regeneration mode. Therefore, when the angle correction unit 82 receives the motor rotation number MRN and the torque command value TR existing in the first quadrant or the second quadrant from the rotation detection unit 81 and the external ECU, respectively, the angle correction unit 82 When it is determined that 60 is in the power running mode and the angle correction unit 82 receives the motor rotation number MRN and the torque command value TR existing in the third quadrant or the fourth quadrant from the rotation detection unit 81 and the external ECU, respectively, The angle correction unit 82 determines that the motor generator 60 is in the regeneration mode.

  FIG. 9 is a relationship diagram between noise and torque ripple. In FIG. 9, the vertical axis represents noise, and the horizontal axis represents torque ripple. Referring to FIG. 9, the relationship between noise and torque ripple is represented by curve k14, and the noise is hardly increased until torque ripple reaches threshold value Trpth, and is proportional to torque ripple when torque ripple exceeds threshold value Trpth. growing.

  In the present invention, the noise reference value LV is set, and the torque ripple value Trp1 at which the noise becomes the reference value LV is extracted from the curve k14. Then, the relationship between the torque and the current advance angle when the torque ripple becomes the value Trp1 is created by the method described in FIG. 4, and the created relationship between the torque and the current advance angle is stored in the angle correction unit 82 as a map. Keep it.

  When receiving the torque command value TR from the external ECU, the angle correction unit 82 extracts the current advance angle from the map so that the torque ripple is equal to or less than the value Trp1.

  Thereby, motor drive device 100 can drive motor generator 60 so that the torque ripple is equal to or less than value Trp1.

  That is, the motor drive device 100 according to the first embodiment is not limited to the motor drive device that drives the motor generator 60 so that the torque ripple is minimized, but the motor that drives the motor generator 60 so that the torque ripple is equal to or less than a predetermined value. Any driving device may be used.

  Angle correction unit 82 constitutes “phase angle determination means” that performs a phase angle determination process for determining a suitable current phase angle for flowing current to motor generator 60 such that torque ripple is equal to or less than a predetermined value.

  The inverter 40, the three-phase / two-phase converter 83, the current command generator 84, the subtractors 85 and 86, the PI controller 87, the two-phase / three-phase converter 88, and the PWM generator 89 are phase angle determining means. “Control means” for driving and controlling the motor generator 60 using the phase angle determined by the (angle correction unit 82) is configured.

[Embodiment 2]
FIG. 10 is a schematic block diagram of a motor drive device according to the second embodiment. Referring to FIG. 10, motor drive device 100A according to the second embodiment is the same as motor drive device 100 except that control device 80 of motor drive device 100 shown in FIG. It is.

  The control device 80A is the same as the control device 80 except that the angle correction unit 82 of the control device 80 is replaced with an angle correction unit 82A.

  The motor drive device 100A is mounted on a hybrid vehicle or an electric vehicle. Motor generator 60 drives the drive wheels of the hybrid vehicle or electric vehicle.

  A case where the motor drive device 100A is mounted on a hybrid vehicle will be described. When the hybrid vehicle travels only by the motor generator 60, the angle correction unit 82A determines the current advance angle so that the torque ripple is minimized according to the curve k2 shown in FIG. 3, and the hybrid vehicle has the motor generator 60 and the engine (not shown). 3), the current advance angle is determined so as to minimize the current according to the curve k3 shown in FIG.

  Note that the angle correction unit 82A can determine whether the hybrid vehicle is driven by the motor generator 60 alone or by the motor generator 60 and the engine based on a signal received from a control device (not shown) that controls the entire hybrid vehicle.

  Then, the angle correction unit 82A corrects the sensor value θ from the rotational position sensor 70 using the current advance angle α determined according to the curve k2 or k3 shown in FIG. 3, and sets the corrected correction value θ + α to three-phase / 2. Output to phase conversion unit 83 and 2-phase / 3-phase conversion unit 88.

  Then, the three-phase / two-phase conversion unit 83, the current command generation unit 84, the subtractors 85 and 86, the PI control unit 87, the two-phase / three-phase conversion unit 88, and the PWM generation unit 89 are hybrid vehicles only for the motor generator 60. When the vehicle travels by using the correction value θ + α from the angle correction unit 82A, a signal PWM for driving the motor generator 60 is generated so as to minimize the torque ripple and is output to the inverter 40. When traveling by the engine, a signal PWM for driving the motor generator 60 is generated and output to the inverter 40 using the correction value θ + α from the angle correction unit 82A so as to minimize the current.

  As a result, the motor drive device 100A drives the motor generator 60 so that torque ripple is minimized when the hybrid vehicle travels only by the motor generator 60. When the hybrid vehicle travels by the motor generator 60 and the engine, the current is The motor generator 60 is driven so as to be minimized.

  As a result, in a quiet travel mode in which the hybrid vehicle travels only by the motor generator 60, torque ripple generated by the motor generator 60 can be minimized, and noise in the hybrid vehicle can be reduced.

  When the hybrid vehicle travels only by the motor generator 60, the angle correction unit 82A determines the current advance angle α so that the torque ripple is equal to or less than a predetermined value, and the motor drive device 100A determines that the torque ripple is equal to or less than the predetermined value. Thus, the motor generator 60 may be driven.

  Next, a case where the motor drive device 100A is mounted on an electric vehicle will be described. When the electric vehicle travels at an acceleration, the angle correction unit 82A determines the current advance angle so as to minimize the current according to the curve k3 shown in FIG. 3, and when the electric vehicle travels in a mode other than the acceleration travel, FIG. The current advance angle is determined so that the torque ripple is minimized according to the curve k2.

  Note that the angle correction unit 82A can determine whether the electric vehicle travels in an acceleration mode or a mode other than the acceleration travel based on a signal received from a control device (not shown) that controls the entire electric vehicle.

  Then, the angle correction unit 82A corrects the sensor value θ from the rotational position sensor 70 using the current advance angle α determined according to the curve k2 or k3 shown in FIG. 3, and sets the corrected correction value θ + α to three-phase / 2. Output to phase conversion unit 83 and 2-phase / 3-phase conversion unit 88.

  Then, the three-phase / two-phase conversion unit 83, the current command generation unit 84, the subtractors 85 and 86, the PI control unit 87, the two-phase / three-phase conversion unit 88, and the PWM generation unit 89 are used when the electric vehicle travels at an acceleration. The signal PWM for driving the motor generator 60 is generated using the correction value θ + α from the angle correction unit 82A so as to minimize the current, and is output to the inverter 40, so that the electric vehicle travels in a mode other than the acceleration travel mode. In this case, the correction value θ + α from the angle correction unit 82A is used to generate a signal PWM for driving the motor generator 60 so as to minimize the torque ripple, and output it to the inverter 40.

  As a result, the motor drive device 100A drives the motor generator 60 so that the current is minimized when the electric vehicle travels at an acceleration, and the torque ripple is minimized when the electric vehicle travels in a mode other than the acceleration travel. The motor generator 60 is driven.

  As a result, in a quiet travel mode in which the electric vehicle travels in a mode other than acceleration travel, torque ripple generated by the motor generator 60 can be minimized, and noise in the electric vehicle can be reduced.

  When the electric vehicle travels in a mode other than acceleration traveling, the angle correction unit 82A determines the current advance angle α so that the torque ripple is equal to or smaller than a predetermined value, and the motor drive device 100A determines that the torque ripple is equal to or smaller than the predetermined value. The motor generator 60 may be driven as described above.

  The motor drive device 100A is not limited to the motor drive device that directly supplies the DC voltage from the DC power supply 10 to the inverter 40, but is a motor drive device that boosts the DC voltage from the DC power supply 10 and supplies it to the inverter 40. Alternatively, it may be a motor drive device that mainly supplies a DC voltage from the fuel cell to the inverter 40 and supplies a DC voltage from the DC power source 10 to the inverter 40 when power from the fuel cell is insufficient. .

  That is, in the present invention, the electric vehicle includes a fuel cell vehicle.

  The angle correction unit 82A performs a first phase angle determination process for determining a first phase angle of the current flowing through the motor generator 60 so that the torque ripple is equal to or less than a predetermined value in the first operation mode. Performing a second phase angle determination process for determining a second phase angle of the current flowing through the motor generator so that the current flowing through the motor generator is minimized in the second operation mode other than the above operation mode. Is configured.

  The inverter 40, the three-phase / two-phase converter 83, the current command generator 84, the subtractors 85 and 86, the PI controller 87, the two-phase / three-phase converter 88, and the PWM generator 89 are phase angle determining means. “Control means” that drives and controls the motor generator 60 using the first phase angle or the second phase angle determined by the (angle correction unit 82A) is configured.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applied to a motor drive device capable of accurately reducing torque ripple. The present invention is also applied to a motor drive device that can accurately reduce torque ripple when noise reduction is required. Furthermore, the present invention is applied to a motor drive device capable of accurately reducing torque ripple according to the operation mode of the motor generator.

1 is a schematic block diagram of a motor drive device according to Embodiment 1 of the present invention. It is a circuit diagram of the inverter shown in FIG. FIG. 4 is a relationship diagram between torque and current advance angle. It is a related figure of torque ripple and torque. It is a relationship figure of an electric current and a torque. It is a conceptual diagram for measuring the noise and vibration in a motor generator. FIG. 7 is a diagram illustrating a vibration-rotational speed relationship and a sound-rotational speed relationship measured under the conditions described in FIG. 6. FIG. 6 is a relationship diagram between motor regenerative sound and braking force distribution and motor rotation speed. It is a related figure of noise and torque ripple. FIG. 5 is a schematic block diagram of a motor drive device according to a second embodiment.

Explanation of symbols

  1 power line, 2 ground line, 10 DC power supply, 12 voltage sensor, 15 U-phase arm, 16 V-phase arm, 17 W-phase arm, 30 capacitor, 40 inverter, 50 current sensor, 60 motor generator, 61 face plate, 62 vibration Pick, 63 microphone, 70 rotational position sensor, 80, 80A control device, 81 rotational speed detection unit, 82, 82A angle correction unit, 83 3-phase / 2-phase conversion unit, 84 current command generation unit, 85, 86 subtractor, 87 PI control unit, 88 2-phase / 3-phase conversion unit, 89 PWM generation unit, 100, 100A motor drive device, Q1-Q6 NPN transistor, D1-D6 diode.

Claims (10)

Phase angle determination for determining a suitable current phase angle for causing a current to flow through the motor generator so that a torque ripple representing a fluctuation rate of the actually output torque with respect to the average value of the torque output from the motor generator is equal to or less than a predetermined value. Phase angle determining means for performing processing;
A motor drive device comprising: control means for driving and controlling the motor generator using the determined preferred current phase angle.   The phase angle determining means holds a map indicating a relationship between the torque and the current phase angle when the torque ripple is equal to or less than the predetermined value, and determines a current phase angle corresponding to the input torque command value. The motor drive device according to claim 1, wherein the suitable current phase angle is determined by extraction from the map.   3. The motor drive device according to claim 1, wherein the phase angle determination unit performs the phase angle determination process when the number of rotations of the motor generator is within a predetermined range in the regeneration mode of the motor generator. .   3. The motor drive device according to claim 1, wherein the phase angle determination unit performs the phase angle determination process when noise of a reference value or less is required in the power running mode of the motor generator. In the first operation mode, a first current for causing a current to flow through the motor generator so that a torque ripple indicating a fluctuation rate of the actually output torque with respect to the average value of the torque output from the motor generator is equal to or less than a predetermined value. Performing a first phase angle determination process for determining a phase angle, and flowing a current to the motor generator so that a current flowing to the motor generator is minimized in a second operation mode other than the first operation mode. Phase angle determination means for performing a second phase angle determination process for determining the second current phase angle of
A motor drive apparatus comprising: control means for driving and controlling the motor generator using the determined first current phase angle or the second current phase angle.   The phase angle determining means includes a first map showing a relationship between the torque and the current phase angle when the torque ripple is less than or equal to the predetermined value, and the torque when the current flowing through the motor generator is minimized. And a second map indicating the relationship between the current phase angle and the current phase angle corresponding to the torque command value input in the first operation mode is extracted from the first map. The first current phase angle is determined, the current phase angle corresponding to the torque command value input in the second operation mode is extracted from the second map, and the second current phase angle is determined. The motor driving device according to claim 5. The first operation mode is a mode in which the hybrid vehicle travels only by the torque generated by the motor generator,
The motor driving device according to claim 5 or 6, wherein the second operation mode is a mode in which the hybrid vehicle travels by torque generated by the motor generator and the internal combustion engine. The first operation mode is a mode in which the electric vehicle travels other than acceleration travel,
The motor drive device according to claim 5 or 6, wherein the second operation mode is a mode in which the electric vehicle performs the acceleration traveling.   9. The phase angle determination unit according to claim 5, wherein the phase angle determination unit performs the first phase angle determination process when the rotational speed of the motor generator is within a predetermined range in the regeneration mode of the motor generator. 2. The motor drive device according to item 1.   The motor driving device according to claim 1, wherein the predetermined value is a minimum value of the torque ripple.

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