WO2010109791A1

WO2010109791A1 - Control device and control method

Info

Publication number: WO2010109791A1
Application number: PCT/JP2010/001641
Authority: WO
Inventors: 野口幸一
Original assignee: 平田機工株式会社
Priority date: 2009-03-24
Filing date: 2010-03-09
Publication date: 2010-09-30
Also published as: KR101292683B1; CN102362423A; KR20110128939A; JP2010226897A; CN102362423B; JP5192430B2

Abstract

A control device has a motor and an electromagnetic brake which are electrically connected to each other and outputs a driving voltage to the motor and the electromagnetic brake. The control device comprises a PWM signal output means for outputting a PWM signal of duty ratio based on a set voltage which is set with respect to the electromagnetic brake in advance, and an electromagnetic brake driving means which receives part of a direct-current (DC) voltage used for driving the motor, converts the part of the DC voltage into a DC voltage in proportion to the duty ratio of the PWM signal outputted from the PWM signal output means, and outputs the converted DC voltage to the electromagnetic brake.

Description

Control apparatus and control method

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

Generally, when a motor and an electromagnetic brake are used in combination, the electromagnetic brake is selected according to the motor specification and application. 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, the motor drive power source has both direct current and alternating current, 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 the case where the drive voltage differs between the motor and the electromagnetic brake while eliminating the need for a unique power supply 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 and outputs a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake. PWM signal output means, and a part of the DC voltage used for driving the motor is input, and a part of the DC voltage is converted to a DC voltage proportional to the duty ratio of the PWM signal output from the PWM signal output means. An electromagnetic brake driving means for converting and outputting to the electromagnetic brake is provided.

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 PWM signal output step outputs a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake. An electromagnetic brake driving step of converting a part of the DC voltage used for driving the motor into a DC voltage proportional to the duty ratio of the PWM signal output in the PWM signal output step and outputting the DC voltage to the electromagnetic brake; There is provided a control method characterized by comprising.

According to the present invention, it is possible to cope with the case where the drive voltage differs 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. 3 is a circuit diagram showing an example of an electromagnetic brake control circuit 20. FIG. FIG. 4 is a diagram illustrating a voltage input to an input unit 21. It is a figure which shows the 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, and in the case of the present embodiment, it is assumed that the brake operates in a non-braking state while the DC voltage is being 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 case of this 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 DC 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 showing 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 blocks 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. Since the controller 15 controls both the motor M and the electromagnetic brake Bk and does not go through the CPU 11, it is possible to stop the drive of the motor M and minimize the time lag in the event of an emergency, and to put the brake Bk into a braking state. . 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 the present 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 an 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 case of this 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. The light emitting element (LED in this embodiment) 23a and the light receiving element (in this embodiment, a phototransistor). ) 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 to turn on / off the switching element 24. 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 illustrating a voltage input to the input unit 21 and illustrates a DC voltage V on the bus bb. FIG. 3C shows the voltage output from the terminal 2a, which is the 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 per unit time between t ₀ and t The average voltage 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 will be 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 will be 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

A control device in which a motor and an electromagnetic brake are electrically connected to each other and outputs a drive voltage to them,
PWM signal output means for outputting a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake;
A part of the DC voltage used for driving the motor is input, and 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 to the electromagnetic brake. Electromagnetic brake driving means for outputting;
A control device comprising:
2. The control device according to claim 1, further comprising AC-DC converting means for receiving an AC voltage and converting the AC voltage into a DC voltage used for driving the motor.
A motor driving means for inputting a DC voltage and outputting a driving voltage to the motor is provided.
The control device according to claim 1, wherein a part of the DC voltage input to the motor driving unit is input to the electromagnetic brake driving unit.
The motor driving means is
The control device according to claim 3, wherein the control device is an inverter that converts an input DC voltage into an AC voltage and outputs the drive voltage to the motor.
The electromagnetic brake driving means includes
A first switching element that switches between output and cutoff of a part of a DC voltage used for driving the motor to the electromagnetic brake;
A second switching element that receives the PWM signal output from the PWM signal output means and turns on / off the first switching element in accordance with the PWM signal;
The control device according to claim 1, further comprising:
The first switching element is an FET;
The control device according to claim 5, wherein the second switching element is a photocoupler.
The PWM signal output means includes
A calculating means for calculating the duty ratio based on the set voltage 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 device according to claim 1, further comprising:
A DC voltage used for driving the motor is constantly measured, and a measurement unit that feeds back a measurement result to the calculation unit is provided.
The control device according to claim 7, wherein the calculation unit adjusts the duty ratio based on a measurement result of the measurement unit.
The PWM signal output means includes
A calculating means for calculating the duty ratio based on the set voltage and outputting information indicating the calculated duty ratio;
An FPGA for outputting the PWM signal to the electromagnetic brake driving means based on the information output by the calculation output stage;
The FPGA is
The control device according to claim 3, wherein the control device outputs a control signal to the motor driving unit and, when a predetermined emergency stop condition is satisfied, stops the motor and activates the electromagnetic brake.
A control method for outputting a drive voltage to a motor and an electromagnetic brake,
A PWM signal output step of outputting a PWM signal having a duty ratio based on a preset voltage set for the electromagnetic brake;
An electromagnetic brake driving step of converting a part of the DC voltage used for driving the motor into a DC voltage proportional to the duty ratio of the PWM signal output in the PWM signal output step and outputting the DC voltage to the electromagnetic brake;
A control method comprising:
A measurement step of constantly measuring a DC voltage used for driving the motor;
Adjusting the duty ratio based on the measurement result of the measurement step;
The control method according to claim 10, further comprising: