JP4063209B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device.

  2. Description of the Related Art Conventionally, servo motors and servo amplifiers are often used because FA system devices such as semiconductor manufacturing devices, robots, and various machine tools require high-precision positioning. A system configuration diagram of the servo amplifier is shown in FIG. The servo motor is connected to a rotor with an encoder 9 for detecting rotation information of the motor, and outputs 10,000 pulses or more per rotation. The output pulses are counted by the feedback pulse counter 10. The servo amplifier drives the servo motor in accordance with a command from the host controller (command output device 1), for example, a sequencer, etc., and the servo motor is adjusted so that the position information fed back from the encoder or resolver matches the command from the host controller. Perform the control action. The command from the command output device 1 is generally a command by a pulse. The command pulse output from the command output device 1 is received by the pulse input circuit 3 in the motor control device 2, and the command pulse counter 4 counts the number of pulses for each cycle. The deviation between the counted command pulse number and the pulse number counted by the feedback pulse counter is calculated by the deviation counter 6, and the motor is controlled by the control means 7 so that this deviation becomes zero.

  Recently, since the speed of the motor and high-precision positioning are required to improve productivity, the frequency of the command pulse is further increased, and the number of cases in which a command is issued with a pulse exceeding 1 Mbps is increasing. The configuration of the pulse input circuit 3 for receiving the command pulse is as shown in FIGS. 12 and 13, and the output circuit of the command output device 1 can be connected to either an open collector or a line driver by using a photocoupler. Is possible. Further, the normal pulse input circuit is provided with a filter to prevent malfunction due to noise. However, noise immunity tends to decrease because the cut-off frequency of the filter needs to be set higher as the command pulse speeds up. In addition, in order to increase noise immunity, the number of cases using line drivers that can transmit signals through differential lines is increasing, but the impedance matching of differential lines cannot be achieved with the input circuit of FIG. Is not limited.

As an improvement measure, there are a method of multiplying the command pulse and a method of dividing the feedback pulse from the encoder to improve the apparent frequency (for example, see Patent Document 1).
JP-A-4-361839

  The problem to be solved is that it is difficult to switch the frequency division / multiplication during operation. Therefore, if high speed is prioritized, undershoot and deviation at the time of stopping increase. If the undershoot or deviation is reduced, the high speed is impaired.

The present invention in order to solve the above problems, a pulse input circuit for inputting a pulse signal, a command pulse counter for counting the pulses number per enter the sampling time the output of the pulse input circuit, the motors a feedback pulse counter for counting the full I over-back pulse encoder to force out in accordance with the rotation angle, and deviation counter for calculating the pulse difference to input command pulse value and the feedback pulse value counted pulse deviation becomes 0 the motor control apparatus for driving a motor by a control unit which controls, at least two or more pulses input circuit, the same number of command pulses counter and the pulse input circuit, a command selector for selecting the output of the command pulse counter wherein the two or more pulses input circuit different configurations, one photocoupler, the other one Consists in-receiver, the pulse value counted by the command pulse counter selected by the command selector to a command value.

Or, a pulse input circuit for inputting a pulse signal, to force out in accordance with the rotation angle of the the command pulse counter for counting the pulses number per sampling time by entering the output of the pulse input circuit, motors encoding a feedback pulse counter for counting the full I over-back pulse da, the deviation counter which enter a command pulse value and the feedback pulse value obtained by counting and calculates the pulse difference, the motor by the control means for controlling so that the pulse deviation becomes 0 the motor control device for driving, comprising at least two or more pulses input circuit, the same number of command pulses counter and the pulse input circuit, a command adder adding the pulse value counted by said plurality of command pulse counter, wherein The pulse value calculated by the command adder is used as the command value.

Or, input a command pulse to at least one pulse input circuit, input a feedback pulse signal from an external scale attached to the equipment to another pulse input circuit composed of line receivers, and deviate the output of the command pulse counter Output to the counter .

  According to the motor control device of the present invention, the motor can be driven with low vibration from low speed to high speed with high accuracy, and the occurrence of overshoot and undershoot can be suppressed. Further, the motor can be prevented from vibrating due to disturbance noise or the like when stopped, and the tact time of the FA apparatus can be shortened.

A pulse input circuit for inputting a pulse signal, a command pulse counter for counting the pulses number per enter the sampling time the output of the pulse input circuit, the encoder to force out in accordance with the rotation angle of the motors drives a feedback pulse counter for counting the full I over-back pulse, a deviation counter which enter a command pulse value and the feedback pulse value obtained by counting and calculates the pulse difference, the motor by the control means for controlling so that the pulse deviation becomes 0 in the motor control device, and at least two pulse input circuit, wherein the pulse input circuit the same number of command pulse counter, comprising a command selector for selecting the output of the command pulse counter, the two or more pulses input circuit Are different in structure, one is a photocoupler, the other is a line receiver, The pulse value counted by the command pulse counter selected in択器 to a command value.

  A motor control device according to the present invention will be described with reference to FIGS.

  FIG. 1 shows a block diagram of a motor control system in Embodiment 1 of the present invention. 1 is a command output device, 2 is a motor control device, 8 is a motor, and 9 is an encoder.

The command output device 1 shows a host controller connected to a servo amplifier such as a sequencer. As shown in FIGS. 2 and 3, the output is generally output by an open collector or a line driver. The command outputs a pulse, and there are three methods as shown in FIGS. According to the method of FIG. 4, when a pulse is output from the controller output 1a, a command is issued in the CCW direction, and when a pulse is output from the controller output 2a, a command is issued in the CW direction. The amount of movement is the number of pulses, and the rising edge of the pulse is counted. The method of FIG. 5 outputs a pulse as a movement amount from the controller output 1a, and the motor rotation direction is CCW when the controller output 2a is H, and CW when the controller output 2a is L. In the method of FIG. 6, the controller output 1a and the controller output 2a are pulses having a phase difference of 90 degrees, and the controller output 2a is CCW when the signal is advanced by 90 degrees and CW when the signal is delayed by 90 degrees. Here, the definitions of CW / CCW, H / L, and detection edge may be reversed. The above is the description of the command output device 1.

Next, the motor control device 2 will be described. The motor control device 2 includes a pulse input circuit 3, a command pulse counter 4, a command selector 5, a deviation counter 6, a control means 7, and a feedback pulse counter 10.

  The feedback pulse counter 10 counts the number of pulses output from the encoder 9 and detects motor position information. For example, in an encoder that outputs 10,000 pulses per revolution, the feedback pulse counter counts from 0 to 9999. Recently, many output signals from encoders are transmitted as serial signals, and in this case as well, the count value is similarly 0 to 9999.

  The deviation counter 6 detects the total command pulse count value 24 obtained by processing the command from the command output device 1 and the pulse value counted by the feedback pulse counter 10 at regular intervals, and calculates the difference.

  The control means 7 controls the motor so that the pulse deviation 25 from the deviation counter 6 becomes zero.

  The pulse input circuit 3 has a circuit configuration as shown in FIG. FIG. 2 shows a photocoupler. In this case, since the output of the command output device 1 can be received by either an open collector or a line driver, it is used as an I / F of a servo amplifier. FIG. 3 includes a line receiver, and the output of the command output device 1 is limited to the line driver. As an advantage of using the line receiver, since it is processed with a differential signal, the influence of common mode noise can be cut. Therefore, the cutoff frequency of the filter can be made smaller than that of the photocoupler, and high-speed pulses can be received.

The command pulse counter 4 counts the pulses output from the pulse input circuit, and moves in the CCW / CW direction by counting up / down according to the H / L of the signal, the phase relationship, etc., or Calculate the amount of movement. A pulse input circuit 3 the instruction pulse counter 4 comprises two or more, and at least another configuration of the photo-coupler and line receiver the configuration of the pulse input circuit 3, you configured to include one or more, respectively. High-speed processing using a line driver output configuration required der lever command output apparatus 1 uses the line receiver to the pulse input circuit 3. Also, when driving at a normal speed, when the pulse input circuit 3 and a versatile photocoupler or line driver, output uses a line receiver in the pulse input circuit 3.

  The command selector 5 selects which command pulse count value is to be used in response to inputs from a plurality of command pulse counters 4. The command pulse count value selected here is output to the deviation counter 6 as a total command pulse count value 24.

  The number of pulse input circuits 3 and command pulse counters 4 is the same. However, the number of pulse input circuits 3 may be plural, the number of command pulse counters 4 may be one, and the number of all pulses may be counted by the same command pulse counter 4. .

  With the above configuration, the motor can be driven with low vibration and high accuracy from low speed to high speed, and the occurrence of overshoot and undershoot can be suppressed. Further, the motor can be prevented from vibrating due to disturbance noise or the like when stopped, and the tact time of the FA apparatus can be shortened.

  A second embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 7, what is different from the first embodiment is a processing method of command pulse count values 23a, 23b, 23c,... From the command pulse counter 4, which will be described.

  The command adder 11 adds the count values of the command pulse count values 23a, 23b, 23c,... Counted by the command pulse counter 4 and outputs a total command pulse count value 24 to the deviation counter 6. This operation will be described with reference to FIGS. FIG. 8 is a diagram in the case where a command is given in the CCW direction when a pulse is given to the command pulse 1a (b), and a command in the CW direction is given when a pulse is given to the command pulse 2a (b). The signals of the pulse input circuit 1 in FIG. 7 are command pulses 1a and 2a, and the signals of the pulse input circuit 2 are command pulses 1b and 2b. When pulses are input to the command pulses 1a and 1b, the number of pulses is counted by the command pulse counters a and b. The counted command pulse count values a and b are added by the command adder 11 to obtain a total command pulse count value 24. By using two configurations of the pulse input circuit 3, the same result as that obtained by performing the double processing is obtained. Next, when a pulse is input only to the command pulse 2a, the total command pulse count value 24 is decremented by one. The command pulses 1a and 1b, 2a and 2b may be either synchronous / asynchronous.

  With the configuration as described above, it is possible to drive with higher accuracy than in the first embodiment, and it is possible to suppress the occurrence of overshoot and undershoot. Further, the motor can be prevented from vibrating due to disturbance noise or the like when stopped, and the tact time of the FA apparatus can be shortened.

  A third embodiment of the present invention will be described with reference to FIGS. The pulse input circuit and the command pulse processing method are the same as those in the first and second embodiments. The difference between the first embodiment and the second embodiment is that one of the pulse input circuits is configured to receive the feedback pulse 31 output from the encoder pulse output unit 30. This encoder pulse output device is a signal output from an encoder that detects the position of a rotor connected to a motor or an external scale attached to equipment. The feedback pulse 31 is input to the pulse input circuit 3. Since the output signal of the encoder pulse output unit 30 is usually composed of a line driver, the pulse input circuit 3 uses a line receiver as shown in FIG. Even when the pulse input circuit 3 is a photocoupler, it can be connected via a line receiver. Next, since the encoder pulse is a signal having a phase difference of 90 degrees, the command pulse counter 4 can process the signal by adopting the counter configuration shown in FIG. The signal counted by the command pulse counter 4 is output to the deviation counter 6. The deviation counter 6 calculates the difference from the signal of the command selector 5 or the command adder 11 and outputs it to the control means 7.

  With the configuration described above, the encoder input and the command input can be shared, so that the number of parts can be reduced.

According to the motor control device of the present invention, the motor can be driven with low vibration from low speed to high speed with high accuracy, and the occurrence of overshoot and undershoot can be suppressed.
It is also useful for avoiding the vibration of the motor due to disturbance noise or the like when stopping, and shortening the takt time of the FA device.

Motor control system block diagram in Embodiment 1 of the present invention First pulse input circuit diagram in Embodiment 1 of the present invention Second pulse input circuit diagram in Embodiment 1 of the present invention The figure which shows the pulse count operation | movement 1 in Example 1 of this invention. The figure which shows the pulse count operation | movement 2 in Example 1 of this invention. The figure which shows the pulse count operation | movement 3 in Example 1 of this invention. Motor control system block diagram in Embodiment 2 of the present invention The figure which shows the pulse count operation | movement in Example 2 of this invention. First motor control system block diagram in Embodiment 3 of the present invention Second motor control system block diagram in Embodiment 3 of the present invention Motor control system block diagram in the prior art First pulse input circuit diagram in the prior art Second pulse input circuit diagram in the prior art

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Command output device 2 Motor control device 3, 3a, 3b, 3c Pulse input circuit 4, 4a, 4b, 4c Command pulse counter 5 Command selector 6 Deviation counter 7 Control means 8 Motor 9 Encoder 10 Feedback pulse counter 11 Command adder 20a1, 20a2, 20-1, 20-2 Controller output 21, 21a, 21b, 21c Amplifier input 22, 22a, 22b, 22c Command pulse 23, 23a, 23b, 23c Command pulse count value 24 Total command pulse count value 25 pulses Deviation 30 Encoder pulse output device 31 Feedback pulse

Claims (3)

A pulse input circuit for inputting a pulse signal, a command pulse counter for counting the pulses number per enter the sampling time the output of the pulse input circuit, the encoder to force out in accordance with the rotation angle of the motors drives a feedback pulse counter for counting the full I over-back pulse, a deviation counter which enter a command pulse value and the feedback pulse value obtained by counting and calculates the pulse difference, the motor by the control means for controlling so that the pulse deviation becomes 0 in the motor control device, and at least two pulse input circuit, wherein the pulse input circuit the same number of command pulse counter, comprising a command selector for selecting the output of the command pulse counter, the two or more pulses input circuit Are different in structure, one is a photocoupler, the other is a line receiver, Motor controller, characterized in that the command value pulse value counted by the command pulse counter selected in択器. A pulse input circuit for inputting a pulse signal, a command pulse counter for counting the pulses number per enter the sampling time the output of the pulse input circuit, the encoder to force out in accordance with the rotation angle of the motors drives a feedback pulse counter for counting the full I over-back pulse, a deviation counter which enter a command pulse value and the feedback pulse value obtained by counting and calculates the pulse difference, the motor by the control means for controlling so that the pulse deviation becomes 0 in the motor control device, comprising at least two or more pulses input circuit, the same number of command pulses counter and the pulse input circuit, a command adder adding the pulse value counted by said plurality of command pulse counter, the command added A motor control device characterized by using a pulse value calculated by a controller as a command value. Input command pulse to at least one pulse input circuit, input feedback pulse signal from external scale attached to equipment to other pulse input circuit composed of line receiver, and output the command pulse counter to deviation counter the motor control device according to claim 1 or claim 2 characterized in that output.

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