JP5192430B2 - Control apparatus and control method - Google Patents

Description

  The present invention relates to a control device and a control method for a motor and an electromagnetic brake.

  In general, when a motor and an electromagnetic brake are used in combination, the electromagnetic brake is selected according to the specification and application of the motor. For this reason, the motor and the electromagnetic brake motor do not necessarily have the same specification combination, and it is often necessary to provide a control unit for each of the motor and the electromagnetic brake. For example, as described in Patent Documents 1 and 2, these control units are preferably common to the motor and the electromagnetic brake. However, in the conventional common unit, the specifications of the motor and the electromagnetic brake are used. Will be limited.

Japanese Patent Laid-Open No. 11-113295 JP-A-11-215892

  However, for example, there are both DC and AC drive power sources for the motor, and various voltages are supplied. The voltage supplied to the electromagnetic brake also varies depending on the manufacturer and purpose of use. For this reason, if the specifications of the motor and the electromagnetic brake are limited, the versatility of the control unit is lost. In order to secure the drive voltage supplied to the electromagnetic brake, it is troublesome to prepare a unique power source each time, and wiring work between the power source and the control unit is also required.

  An object of the present invention is to cope with a case where a drive voltage is different between a motor and an electromagnetic brake while eliminating the need for a unique power source for the electromagnetic brake.

According to the present invention, a motor and an electromagnetic brake are electrically connected to each other, and a control device that outputs a drive voltage to the motor is provided. An AC voltage is input to the DC voltage used for driving the motor. AC-DC conversion means for converting and output, motor driving means for inputting the DC voltage output from the AC-DC conversion means, and outputting the driving voltage to the motor, and outputting the driving voltage to the electromagnetic brake Electromagnetic brake driving means, PWM signal output means for outputting a PWM signal having a duty ratio based on a preset voltage for the electromagnetic brake, and measurement for monitoring the DC voltage output from the AC-DC conversion means and means, and the AC - as a part of the DC voltage outputted from the DC converting means is input to said electromagnetic brake driving unit, said motor The AC and motor drive means and said electromagnetic brake driving means - is connected in parallel for the DC conversion means, the electromagnetic brake driving unit, the PWM output part of the direct current voltage from the PWM signal output unit The DC signal is converted to a DC voltage proportional to the duty ratio of the signal and output to the electromagnetic brake. The PWM signal output means maintains the DC voltage output from the electromagnetic brake driving means to the electromagnetic brake at the set voltage. As described above , a control device is provided that adjusts the duty ratio based on a measurement result of the measuring means and outputs the PWM signal .

According to the present invention, there is also provided a control method for outputting a drive voltage to a motor and an electromagnetic brake, wherein the alternating current voltage is converted into a direct current voltage used for driving the motor by an alternating current-direct current conversion means and output. A DC conversion step, a motor drive step of inputting the DC voltage output from the AC-DC conversion unit to the motor drive unit, and outputting a drive voltage from the motor drive unit to the motor, and an electromagnetic brake drive unit. An electromagnetic brake driving step of outputting a driving voltage to the electromagnetic brake, a PWM signal output step of outputting a PWM signal having a duty ratio based on a preset voltage set in advance for the electromagnetic brake, and an output from the AC-DC converting means and a measurement step for monitoring said DC voltage, the AC - part of the DC voltage outputted from the DC converting means As input to the electromagnetic brake driving unit, said motor driving means and said electromagnetic brake driving means the AC - connected in parallel for the DC conversion means, the electromagnetic brake driving step, by the electromagnetic brake driving means A part of the DC voltage is converted into a DC voltage proportional to the duty ratio of the PWM signal output in the PWM signal output step and output to the electromagnetic brake. In the PWM signal output step, the electromagnetic brake drive The PWM signal is output by adjusting the duty ratio based on the measurement result in the measurement step so that the DC voltage output from the means to the electromagnetic brake is maintained at the set voltage. A control method is provided .

  According to the present invention, it is possible to cope with the case where the drive voltage is different between the motor and the electromagnetic brake while eliminating the need for a unique power source for the electromagnetic brake.

It is a block diagram of control device A concerning one embodiment of the present invention. 2 is a block diagram illustrating an example of a control circuit 10. FIG. (A) is a circuit diagram showing an example of the electromagnetic brake control circuit 20, (b) is a diagram showing a voltage input to the input unit 21, (c) is a diagram showing a voltage output from the terminal 2a. It is a block diagram of control device B concerning other embodiments of the present invention. It is a block diagram of the control apparatus C which concerns on other embodiment of this invention.

<First Embodiment>
FIG. 1 is a block diagram of a control apparatus A according to an embodiment of the present invention. The control device A includes a connection portion 1 to which the motor M is electrically connected and a connection portion 2 to which the electromagnetic brake Bk is electrically connected. In the case of this embodiment, the motor M assumes an AC motor. The electromagnetic brake Bk is driven by a DC voltage. In the present embodiment, it is assumed that the electromagnetic brake Bk operates in a non-braking state while the DC voltage is supplied and in a braking state when the supply is cut off. On the contrary, it may be a braking state during the supply of the DC voltage and a non-braking state when the supply is cut off.

  For example, the electromagnetic brake Bk is connected to the drive shaft of the motor M, and the connecting portions 1 and 2 that stop the rotation of the drive shaft of the motor M in the braking state connect the motor M and the electromagnetic brake Bk, respectively. The control device A outputs a driving voltage from each of the connecting portions 1 and 2 to drive the motor M and the electromagnetic brake Bk. The AC power supply 100 is, for example, a 200V commercial power supply. The control device A has a connection portion 3 to which the AC power supply 100 is electrically connected, and an AC voltage output from the AC power supply 100 is input to the control device A. The control device A includes a connection unit 4 to which a communication line with an external computer is connected. An instruction or the like from an external computer is input to the connection unit 4.

  The control device A includes an AC / DC converter 5. The AC / DC converter 5 is a rectifier that converts the AC voltage input to the connection unit 3 into a DC voltage (for example, 280 V) used for driving the motor M and outputs the DC voltage to the bus bb. A motor drive circuit 6 and an electromagnetic brake drive circuit 20 are connected to the bus bb. That is, the motor drive circuit 6 and the electromagnetic brake drive circuit 20 are connected in parallel to the AC / DC converter 5, and a part of the DC voltage used for driving the motor M on the bus bb (in other words, the DC Part of electric power or direct current) is input to the electromagnetic brake drive circuit 20.

  In the present embodiment, the motor drive circuit 6 is an inverter that converts a DC voltage input via the bus bb into an AC voltage and outputs the AC voltage as a drive voltage. In the case of this embodiment, the motor drive circuit 6 outputs a stop signal for requesting an emergency stop to the control circuit 10 when an abnormality occurs in the drive of the motor M. When a DC motor is employed as the motor M, the motor drive circuit 6 also employs a drive circuit that outputs a DC voltage. At that time, when a voltage different from the direct-current voltage input via the bus bb is output to the motor M, for example, a DC-DC converter or the like can be used. The measurement circuit 7 constantly measures the DC voltage on the bus bb and feeds back the measurement result to the control circuit 10. The measurement circuit 7 constantly measures the DC voltage on the bus bb, thereby monitoring the voltage fluctuation on the bus bb in real time. The measurement circuit 7 is an A / D converter, for example.

  The control circuit 10 outputs a control signal related to the control of the motor M to the motor drive circuit 6. For example, when controlling the rotation speed of the motor M, the control circuit 10 outputs a PWM signal to the motor drive circuit 6 as a control signal. The motor drive circuit 6 changes the speed of the motor M by outputting to the motor M a drive voltage having a frequency proportional to the duty ratio of the input PWM signal. The control circuit 10 also outputs a PWM signal having a duty ratio calculated based on a preset voltage set in advance for the electromagnetic brake Bk to the electromagnetic brake drive circuit 20.

  FIG. 2 is a block diagram illustrating an example of the control circuit 10. The control circuit 10 includes a CPU 11, a RAM 12, a ROM 13, an I / F (interface) 14, and a controller 15. The CPU 11 executes a program stored in the ROM 13. The RAM 12 stores temporary data, and the ROM 13 stores fixed data and programs. These may be other types of storage means. The I / F 14 includes a communication interface that connects an external computer and the CPU 11 via the connection unit 4, and an I / O interface that connects the measurement circuit 7 and the like to the CPU 11. Note that power is supplied to the CPU 11 and the like by a DC power source (not shown).

  The controller 15 is, for example, an FPGA (Field Program Gate Array). In the present embodiment, the controller 15 first outputs a control signal for the motor drive circuit 6 in accordance with an instruction from the CPU 11. Further, a PWM signal is output to the electromagnetic brake drive circuit 20 in accordance with an instruction from the CPU 11. Further, when a stop signal is output from the motor drive circuit 6 to the controller 15, the controller 15 cuts off the power supply to the motor M and the electromagnetic brake Bk without going through the CPU 11. As a result, the driving of the motor M is stopped, and the electromagnetic brake Bk enters a braking state. The controller 15 controls both the motor M and the electromagnetic brake Bk, and does not go through the CPU 11, so that the drive of the motor M can be stopped and the brake Bk can be put into a braking state by minimizing the time lag in an emergency. . In addition, as an emergency stop condition for executing such an emergency stop, in addition to a case where a stop signal is output from the motor drive circuit 6, for example, a case where an emergency stop instruction is received from an external computer via the CPU 11 can be cited. .

  In this embodiment, the CPU 11 calculates the duty ratio of the PWM signal output to the electromagnetic brake drive circuit 20. CPU11 calculates a duty ratio from the setting voltage preset about electromagnetic brake Bk, and the DC voltage on bus-line bb. The set voltage is a target drive voltage to be applied to the electromagnetic brake Bk, and is, for example, 24V or 90V, depending on the type of the electromagnetic brake Bk. For example, the set voltage is input from an external computer via the connection unit 4 and stored in the RAM 12. Alternatively, the type of the electromagnetic brake Bk and each set voltage are stored in the ROM 13, and when the type of the electromagnetic brake Bk is input from the external computer via the connection unit 4, the corresponding set voltage is read from the ROM 13. You may do it.

  In the present embodiment, the DC voltage on the bus bb is the measurement result of the measurement circuit 7. In the case where the measurement circuit 7 is not provided, a DC voltage on the specifications output from the AC / DC converter 5 may be stored in the ROM 13 and regarded as a DC voltage on the bus bb. The duty ratio D of the PWM signal can be calculated from D = (set voltage) / (DC voltage on the bus bb). The CPU 11 outputs information indicating the calculated duty ratio to the controller 15, and the controller 15 outputs a PWM signal having the duty ratio indicated by the information to the electromagnetic brake drive circuit 20.

  As in this embodiment, when the DC voltage on the bus bb is the measurement result of the measurement circuit 7, the CPU 11 calculates the duty ratio in real time and instructs the controller 51 on the duty ratio, so that the motor M generates the regenerative voltage. Even if a voltage fluctuation occurs on the bus bb due to noise or noise mixing, the duty ratio is adjusted according to the voltage fluctuation, and the DC voltage supplied to the electromagnetic brake Bk can be stabilized.

  Next, the electromagnetic brake drive circuit 20 will be described. FIG. 3A is a circuit diagram showing an example of the electromagnetic brake control circuit 20. The electromagnetic brake control circuit includes an input unit 21 that is connected to the bus bb and receives a DC voltage on the bus bb, and an input 22 that receives a PWM signal from the controller 15. In the figure, R is a resistor. The electromagnetic brake drive circuit 20 includes switching elements 23 and 24.

  In the present embodiment, the switching element 24 is an FET, and its drain is connected to one terminal 2 b constituting the connection unit 2. The other terminal 2 a constituting the connection unit 2 is connected to the input unit 21. An electromagnetic brake Bk is connected to the terminals 2a and 2b, and a surge absorbing diode 25 is connected between the terminals 2a and 2b. Therefore, when the switching element 24 is ON, the DC voltage on the bus bb is output to the electromagnetic brake Bk, and when the switching element 24 is OFF, the DC voltage is cut off. Therefore, the output / interruption of the drive voltage to the electromagnetic brake Bk can be switched by turning the switching element 24 ON / OFF.

  In the present embodiment, the switching element 23 is a photoelectric element (for example, a photocoupler) in which the input and the output are insulated from each other. ) 23b. By using a photocoupler in which the input and output are insulated as the switching element 23, the control circuit 10 can be prevented from being affected by noise on the drive circuit side, such as noise on the bus bb, for example. In addition, it is possible to avoid a situation in which the drive voltage is applied to the control circuit 10 due to a failure. The PWM signal from the controller 15 is input to the LED 23a to blink the LED 23a. The collector of the phototransistor 23b is connected to a DC power source (not shown), and is turned on / off by the blinking of the LED 23a, and the switching element 24 is turned on / off. In this way, the output / cutoff of the drive voltage to the electromagnetic brake Bk can be switched by the PWM signal from the controller 15.

FIG. 3B is a diagram showing the voltage input to the input unit 21 and shows the DC voltage V on the bus bb. FIG.2 (c) shows the voltage output from the terminal 2a, and is a drive voltage to the electromagnetic brake Bk. As shown in FIG. 3C, the drive voltage to the electromagnetic brake Bk is a pulse signal corresponding to the duty ratio of the PWM signal. Therefore, by adjusting the pulse width, the drive voltage between t _{0 and} t The average voltage per unit time can be controlled. For this reason, the DC voltage on the bus bb can be converted into the set voltage.

  As described above, in this embodiment, the DC voltage used for driving the motor M is partially used, adjusted to a voltage suitable for driving the electromagnetic brake Bk, and supplied to the electromagnetic brake Bk. Thus, it is possible to cope with the case where the drive voltage is different between the motor M and the electromagnetic brake Bk, while eliminating the need for a power source specific to the motor.

Second Embodiment
In the first embodiment, the control device A includes the AC / DC converter 5. However, a configuration that does not include the AC / DC converter 5 may be employed. FIG. 4 is a block diagram of a control device B according to another embodiment of the present invention. In the figure, the same components as those of the control device A are denoted by the same reference numerals and the description thereof is omitted, and only different components are described below.

  The control device B does not include the AC / DC converter 5 unlike the control device A, and the AC / DC converter 5 has a configuration outside the control device B. A DC voltage output from the AC / DC converter 5 is input to the connection unit 3, and the bus bb is connected to the connection unit 3.

<Third Embodiment>
In the first embodiment, the DC voltage generated in the process of generating the drive voltage of the motor M is used as the DC voltage used for driving the motor M to generate the drive voltage of the electromagnetic brake Bk. May be used. FIG. 5 is a block diagram of a control device C according to another embodiment of the present invention. In the figure, the same components as those of the control device A are denoted by the same reference numerals and the description thereof is omitted, and only different components are described below.

  The control device C does not include the AC / DC converter 5 unlike the control device A, and the AC / DC converter 5 has a configuration outside the control device C. A DC voltage output from the AC / DC converter 5 is input to the connection unit 3, and the bus bb is connected to the connection unit 3. The motor M is a direct current motor, and the control device C does not have the motor drive circuit 6 unlike the control device A. That is, regarding the drive of the motor M, the control device C simply supplies the voltage output from the AC / DC converter 5 to the motor M as it is.

Claims (9)

A control device in which a motor and an electromagnetic brake are electrically connected to each other and outputs a drive voltage to them,
AC-DC conversion means for receiving an AC voltage, converting the AC voltage into a DC voltage used for driving the motor, and outputting the DC voltage;
Motor driving means for inputting the DC voltage output from the AC-DC converting means and outputting a driving voltage to the motor;
Electromagnetic brake driving means for outputting a driving voltage to the electromagnetic brake;
PWM signal output means for outputting a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake;
Measuring means for monitoring the DC voltage output from the AC-DC converting means;
With
Parallel for the DC converter - the AC - as a part of the DC voltage outputted from the DC converting means is input to said electromagnetic brake driving unit, wherein said motor drive means and electromagnetic brake driving means and said AC Connected to
The electromagnetic brake driving means includes
A part of the DC voltage is converted into a DC voltage proportional to the duty ratio of the PWM signal output from the PWM signal output means and output to the electromagnetic brake ;
The PWM signal output means includes
Adjusting the duty ratio based on the measurement result of the measuring means and outputting the PWM signal so that the DC voltage output from the electromagnetic brake driving means to the electromagnetic brake is maintained at the set voltage. Control device characterized. The PWM signal output means includes
A calculation unit that calculates the duty ratio based on the set voltage and a measurement result of the measurement unit, and outputs information indicating the calculated duty ratio;
A controller that outputs the PWM signal to the electromagnetic brake driving means based on the information output by the calculation output stage;
The control device according to claim 1 , further comprising: It said measuring means, the AC - output from the DC converting means and the constantly measured DC voltage, the control device according to the measurement results to claim 2, wherein the feedback to Turkey to the arithmetic unit. The controller is
Follow the instructions of the arithmetic unit, the one which in addition to the output of the PWM signal also performs output of the control signal against said motor drive means, when the predetermined emergency stop condition is satisfied, the at instruction without the operation means The control device according to claim 1, wherein power supply to the motor and the electromagnetic brake is cut off, thereby stopping the motor and putting the electromagnetic brake in a braking state . The control device according to claim 4, wherein the predetermined emergency stop condition is when a stop signal is output from the motor driving unit to the controller. A control method for outputting a drive voltage to a motor and an electromagnetic brake,
An AC-DC conversion step of converting and outputting an AC voltage to a DC voltage used for driving the motor by an AC-DC conversion means;
A motor driving step of inputting the DC voltage output from the AC-DC converting means to a motor driving means, and outputting a driving voltage from the motor driving means to the motor;
An electromagnetic brake driving step of outputting a driving voltage to the electromagnetic brake by an electromagnetic brake driving means;
A PWM signal output step of outputting a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake;
A measuring step of monitoring the DC voltage output from the AC-DC converting means;
With
Parallel for the DC converter - the AC - as a part of the DC voltage outputted from the DC converting means is input to said electromagnetic brake driving unit, wherein said motor drive means and electromagnetic brake driving means and said AC Connected to
In the electromagnetic brake driving process,
The electromagnetic brake driving means converts a part of the DC voltage into a DC voltage proportional to the duty ratio of the PWM signal output in the PWM signal output step, and outputs the DC voltage to the electromagnetic brake .
In the PWM signal output step,
Adjusting the duty ratio based on the measurement result in the measurement step and outputting the PWM signal so that the DC voltage output from the electromagnetic brake driving means to the electromagnetic brake is maintained at the set voltage. A control method characterized by the above. The PWM signal output step includes
A calculation means for calculating the duty ratio based on the set voltage and a measurement result of the measurement step, and outputting information indicating the calculated duty ratio;
A controller that outputs the PWM signal to the electromagnetic brake driving means based on the information output by the calculation output stage;
The control method according to claim 6, wherein the control method is executed by: The controller also outputs a control signal to the motor driving means in addition to the output of the PWM signal in accordance with an instruction from the arithmetic means.
In the control method, when a predetermined emergency stop condition is satisfied, the controller cuts off the power supply to the motor and the electromagnetic brake without an instruction from the calculation means, thereby stopping the motor and the electromagnetic brake. The control method according to claim 7, further comprising a step of setting the brake to a braking state. 9. The control method according to claim 8, wherein the predetermined emergency stop condition is when a stop signal is output from the motor driving means to the controller.

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