JPH0260490A - Drive controller - Google Patents

Abstract

PURPOSE:To reduce a torque ripple and cogging by driving a motor device, etc., by switching and changing the amplitude of switching pulses in response to the operation of the motor device, etc. CONSTITUTION:A drive controller has a speed amplifier 51, current amplifiers 52-54, a three-phase sine wave generating circuit 55, a rotor-position detector 56, a triangular wave generating circuit 57, comparators 58-60, drivers 61-66, an output variable power circuit 67, a transistor bridge 68, a DC brushless motor 69 connected to the bridge 68, a rotary encoder 70, a speed detector 71, etc. A speed feedback signal 502 by the speed detector 71 is subtracted from a speed reference signal 501, and a speed command 503 is generated through the speed amplifier 51. On the other hand, the current feedback signals 523-524 of the motor 69 are extracted, and the signals corresponding to each phase are subtracted from said speed command 503, and values acquired are output through the current amplifiers 52-54. Accordingly, the amplitude of driving power supply pulses is also changed to a sine wave shape in response to the operation of the motor 69, thus reducing cogging, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a drive control device, and the present invention relates to a drive control device, and for example, when driving a motor by switching, a PAM (pulse amplitude modulation) method is used in combination to reduce torque ripple and smooth the drive control device. This invention relates to a drive control device that enables operation.

(Prior art) Conventionally, for example, when controlling the drive of a DC brushless motor, a power control circuit based on the PWM (pulse width modulation) method as shown in Figure 4 has been used (Sogo Denshi Publishing, Brushless Servo). Basics and applications of motors,
Dote original intention, edited by Fumitake Kinoshita, p. 22, see Figure 2.6).

In the circuit of FIG. 4, given speed reference signal 10
1 and the speed detection signal 102 generated by the rotary encoder 21 and the speed detection circuit 22, an error signal 104 is generated. Further, in accordance with the rotation of the motor 20, the rotor position detection circuit 7 and the sine wave generation circuit 6 generate a two-phase sine wave 103 corresponding to the rotation of the motor 2o,
The signals of each phase of this two-phase sine wave 10B and the error signal],
04 respectively in the DC/SIN conversion circuit 2 to generate current reference signals ]05 and 106. Further, these current reference signals 105 and 106 are added to generate a third phase current reference signal 129.

Further, voltage signals corresponding to the current flowing through the motor 20 are generated as current feedback signals 126, 127, 128, and these current feedback signals are subtracted from the current reference signals 105 to 106129 for each phase to generate current amplifier signals 108, 109. Generate .110. These current amplifier signals 1.08, 109, 110 are input to each comparator 9.10.11 together with the output signal 107 of the triangular wave generation circuit 8 to generate PWM signals 111, 112.., 116. Dry PWM signal/
<12. 13. . . , 17 and the transistor bridge 19 to generate final drive outputs 123.124125 to drive the motor 20. The transistor bridge 19 is supplied with a constant voltage DC power of, for example, 100V or 200V from the power supply circuit 18.

FIG. 5 shows the signal waveforms of each part of the circuit in FIG.
a) shows the current amplifier output, for example 1.08, and the same figure (
2.b) shows the output signal 107 of the triangular wave generation circuit 8, and FIG. 2(c) shows the motor drive output, that is, the pseudo sine wave output. As mentioned above, in the circuit of Fig. 4, P
Since the motor 21 is switched and driven using the WM method to control the power of, for example, an inverter air conditioner compressor or a DC brushless servo motor, it is possible to generate relatively little heat and reduce power consumption.

(Problem to be Solved by the Invention) However, in the circuit shown in FIG. 4, since a pulse-shaped square wave with a constant amplitude as shown in FIG. 5(c) is used as the drive output of the motor, the torque ripple is large. Particularly when the motor rotates at low speed, smooth rotation is not achieved and so-called cogging increases.

In view of the problems with the conventional devices described above, an object of the present invention is to provide a drive that enables smooth operation with less torque ripple without sacrificing the energy saving and reduced heat generation characteristics of the switching drive. The purpose is to provide a control device.

(Means for Solving the Problems) A drive control device according to the present invention includes a waveform signal generating means that generates a waveform signal whose amplitude changes depending on the operating phase of a motor device, and an output level that changes based on the waveform signal. It includes a variable output power supply circuit that supplies power, and a drive means that switches the output of the variable output power supply circuit and supplies it to the motor device. Further, the driving means can also perform the switching in a time width regulated by a pulse width modulated signal based on the speed command signal and/or the current feedback signal. Furthermore, the variable output power supply circuit
It is also possible to change the output level based on a signal obtained by combining the speed command signal and the waveform signal.

(Function) In the above-described configuration, a sine wave-like waveform signal, for example, is generated in response to the operation of the motor device. The variable output power supply circuit outputs a power supply whose output level changes, for example, in a sinusoidal manner based on this waveform signal.

The motor device is driven by switching the sinusoidally changing power supply to the motor device by the driving means. Therefore, the amplitude of the drive power pulse supplied from the drive means to the motor device can also be changed, for example, in a sinusoidal manner according to the operation of the motor device, thereby making it possible to extremely reduce torque ripple and cogging of the motor device.

(Example) Hereinafter, the present invention will be explained in detail with reference to the drawings.

FIG. 1 shows a circuit configuration of a drive control device according to an embodiment of the present invention. The device in the figure includes a speed amplifier 51, current amplifiers 52, 53, 54, a three-phase sine wave generating circuit 55, a rotor position detecting circuit 56, a triangular wave generator 57, comparators 58, 59, 60, a driver 61. 62. ..., 6
6. Output variable power supply circuit 67, transistor bridge 68
, connected to the transistor bridge 68, e.g.
A motor 69 such as a brushless motor, and a rotary encoder 7 that outputs a predetermined signal according to the rotation of the motor 69.
0. It includes a speed detection circuit 71 and the like.

The three-phase sine wave generation circuit 55 is configured using, for example, a read-only memory, and supplies three phases of sine wave signals to the variable output power supply circuit 67. Further, the rotary encoder 70 can be, for example, a resolver or any other device that can output a signal corresponding to the rotation of the motor 69.

Note that the motor 69 is not limited to one that performs rotational motion, and may be, for example, a linear motor.

The operation of the apparatus shown in FIG. 1 will be explained with reference to FIG. Jj
A speed command 503 is generated by subtracting the speed feedback signal 502 given by the speed detection circuit 71 from the obtained speed reference signal 501 and amplifying it in the speed amplifier 5]. On the other hand, current feedback signals 523 and 524 corresponding to the current flowing to the motor 69 are extracted from the three-phase drive output of the motor 69, and the current feedback signals 523 and 524 for these two phases are added and inverted to obtain the current of other phases. A feedback signal 525 is generated. Then, the current feedback signal for each phase is subtracted from the speed command 503 mentioned above, and the current feedback signal for each phase is amplified by the current amplifiers 52, 53, 54, and the current amplifier outputs 504, 505,
Get 506. FIG. 2(a) shows a signal for one phase of these current amplifier outputs. Next, these current amplifier outputs 504, 505, 506 are connected to each comparator 585.
At 9.60, each driver 61, 62, . . .
, 66 are square wave PWM signals 508, 509 . . , as shown in FIG. 2(C). ..., send 51B. In addition, the second
Figure (b) does not show the output 507 of the triangular wave generator 57. The motor 69 is driven by current amplifying the PWM signal in each of the drivers 61, 62, . . . , 66 and switching each switching transistor of the transistor bridge 68. On the other hand, the rotor position detection circuit 56 outputs a signal that changes in accordance with the rotational position of the rotor of the motor 69 based on the output signal from the rotary encoder 70. The three-phase sine wave generation circuit 55 is
A three-phase sine wave signal 526 having a phase determined from the rotor position of the motor 69 is generated and fed back to the variable output power supply circuit 67. As a result, the output variable power supply circuit 67 changes the amplitude of the output power 527, 528, and 529 of each phase in a sinusoidal manner, for example, as shown in FIG. 2 (( )) according to the rotation of the motor 69. The amplitude of the drive pulse supplied to the motor 69 also changes according to the rotation of the motor 69, as shown in FIG. 2(e). Although the output voltage of the motor 69 and the amplitude of the drive pulse applied to the motor 69 are shown to change over both positive and negative polarities, in reality, for example, each output 527, 528, 529 of the variable output power supply circuit 67 changes.
The circuit configuration can be simplified by setting the voltage to a waveform obtained by rectifying the waveform shown in FIG. 2(d). Therefore, in this case, the output pulses supplied to the motor 69 are also shown in FIG.
) is the full-wave rectified waveform.

Further, the transistor bridge 68 includes, for example, two transistors connected in series between the power supply and ground for each phase,
Therefore, the configuration can be basically made up of six transistors in total, but in FIG. 1, a dead time generating circuit for preventing the upper and lower transistors of each phase from turning on at the same time is omitted. Further, the transistor bridge 68 can also be realized by a power device such as a power MO8FET or a GTO.

In this manner, in the apparatus of FIG.
As shown in FIG. 2(e), the amplitude of the drive pulse applied to the drive pulse changes in accordance with the rotation of the motor 69, so that the 1 to 1 ripple of the motor 69 is extremely small and so-called cogging is also avoided. Does not occur. In FIG. 1, the output level of the variable output power supply circuit 67 has been described as changing in a sinusoidal waveform, but this is not limited to a sinusoidal waveform, and may be changed, for example, along a trapezoidal waveform or any other suitable waveform. It can be changed.

FIG. 3 shows a circuit configuration of a drive control device according to another embodiment of the present invention. The device in the figure includes a speed accordion 81, a multiplier 82, a variable output power supply circuit 83, a triangular wave generator 84.3 phase ratio sinusoidal wave generation circuit 85, a rotor position detection circuit 86, a speed detection circuit 87, and a comparator 88. ,89
．． QO, driver 91. ．． 92, 93, . . , 96, a transistor bridge 97, a motor 98, and a rotary encoder 99. Note that the rotary encoder 99 can also be configured by a resolver or the like as described above.

In the apparatus shown in FIG. 3, the obtained speed reference signal 8
A speed command signal 803 obtained by subtracting the output 802 of the speed detection circuit 87 from 01 is input to the multiplier 82 . Nine rotary encoders, a rotor position detection circuit 86, and a three-phase sinusoidal wave signal 8 generated by a three-phase ratio sinusoidal wave generation circuit 85.
04 is converted into a speed command signal 80 for each phase by a multiplier 82.
3 to obtain a power supply control signal 824 corresponding to each phase, which causes the output variable power supply circuit 83 to output 825.8.
26,827. Note that in order to vary the outputs of the three phases of the variable output power supply circuit 83, a corresponding one to the multiplier 82 can be provided for each phase. On the other hand, the drive current of the motor 98 is detected to generate current feedback signals 821, 822, 823 for each layer, and the output 805 of the triangular wave generator 84 is output to each comparator 88, 8990.
Compare with. This allows each comparator to output a square wave P
WM signals 806, 807. . . , 811 are obtained, and these signals are transmitted to the drivers 91, 92 . ..., 96 to the transistor bridge 97, and the motor 98 is switched and driven in the same manner as described above.

Note that the current feedback signals 821, 822, and 823 are generated when, for example, an excessive current flows through the motor 98 and the transistor bridge 97
It functions to prevent destruction of the Also, multiplier 2
It is also possible to digitize data.

(Effects of the Invention) As described above, according to the present invention, since the motor device etc. is driven by switching and the amplitude of the switching pulse is changed according to the operation of the motor device etc., torque ripple and cogging are extremely minimized. (7) It is possible to perform smooth operation. Also, since the device according to the present invention switches and drives a motor device, it goes without saying that a circuit with low heat generation and low power consumption can be realized. Output variable power supply circuits 67 and 8
If B is constructed using a switching regulator system, for example, it is possible to further save energy and reduce heat generation.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing the configuration of a drive control device according to an embodiment of the present invention, FIG. 2 is a waveform diagram for explaining the operation of the device shown in FIG. 1, and FIG. FIG. 4 is an electric circuit diagram showing the configuration of a drive control device according to another embodiment of the invention; FIG. 4 is an electric circuit diagram showing the configuration of a conventional drive control device; and FIG. FIG. 2 is a waveform diagram for explaining. 51.81 + speed amplifier, 52.53, 54: current amplifier, 55.85: 3-phase ratio sinusoidal wave generation circuit, 56.86 + rotor position detection circuit, 57.84: triangular wave generator, 58, 59. 60. 88.89. 90: Comparator, 61.62. ..., 66.91,92.・・・
・96 driver, 67.83: variable output power supply circuit, 68.97: transistor bridge, 69.98: motor, 70.99: rotary encoder. Patent applicant Mitsui Metal Mining Co., Ltd.

Claims (1)

[Scope of Claims] 1. Waveform signal generation means for generating a waveform signal whose amplitude changes in accordance with the operating phase of the motor device; a variable output power supply circuit that supplies a power source whose output level changes based on the waveform signal; and a drive means for switching the output of the variable output power supply circuit and supplying the switched output to the motor device. 2. A waveform signal generating means for generating a waveform signal whose amplitude changes in accordance with the operating phase of the motor device; a variable output power supply circuit that supplies a power source whose output level changes based on the waveform signal; speed detection means for outputting a corresponding speed signal; comparison means for generating an error signal by comparing the value of the speed signal with a reference value; and a pulse width for generating a switching signal having a pulse width corresponding to the value of the error signal. A drive control device comprising: modulation means; and drive means for switching the output of the variable output power supply circuit in a time width regulated by the switching signal and supplying the switched output to the motor device. 3, further comprising current detection means for generating a current feedback signal corresponding to the magnitude of the current flowing through the motor device, and subtraction means for generating a corrected error signal by subtracting the current feedback signal from the error signal, 3. The drive control device according to claim 2, wherein the pulse width modulation means generates a switching signal having a pulse width corresponding to the value of the corrected error signal. 4. Speed detection means for outputting a speed signal corresponding to the operating speed of the motor device; comparison means for generating an error signal by comparing the value of the speed signal with a reference value; A waveform signal generating means for generating a changing waveform signal, a multiplier for generating a power control signal by multiplying the error signal and the waveform signal, and a variable output device for supplying power whose output level changes based on the power control signal. A drive control device comprising: a power supply circuit; and a drive means for switching the output of the variable output power supply circuit and supplying the switched output to the motor device. 5. Further, current detection means for generating a current feedback signal corresponding to the magnitude of the current flowing through the motor device, and pulse width modulation means for generating a switching signal having a pulse width corresponding to the value of the current feedback signal. 5. The drive control device according to claim 4, wherein the drive means switches the output of the variable output power supply circuit in a time width regulated by the switching signal and supplies the output to the motor device.