JPH09219972A - Motor controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller more compact even though the operation of the controller can be continued after giving an emergency stop to a motor in the configuration. SOLUTION: A first terminal 24 for connecting an AC power supply 30 of one system and a second terminal 23 for connecting an electromagnetic switch 33, which is to be opened when giving an emergency stop to the motor 22, are provided. An AC power supply 30 is rectified by a diode bridge 25 through the first terminal 24 and then supplies power to an inverter portion 29 and a control power supply generating portion 27. If the second terminal 23 is connected in series to the middle of wiring to the inverter portion 29 from one side of the output of the diode bridge 25, the electromagnetic switch 33 opens and the power supply to the motor 22 is interrupted, but the internal controller is able to continue its operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an electric motor, which can keep the internal power supply of the control device alive even after the electric motor is stopped in an emergency.

[0002]

2. Description of the Related Art In recent years, in the case of emergency stopping of a machine using an electric motor, a method of cutting off the power source of the electric motor while keeping the power source inside the control device of the electric motor alive has become mainstream.

FIG. 2 is a circuit diagram of a conventional motor control device, the structure of which will be described below. In FIG. 2, the control device 1 of the electric motor 2 generates a terminal 11 for applying an AC power supply 3 for supplying electric power to the control power supply generation unit 7 for operating the control device 1, and an AC voltage applied to the electric motor 2. It has a terminal 13 for applying an AC power supply 4 for supplying electric power to the inverter unit 10. The AC power supply 3 turns on the control device 1.
It is applied to the inside of the control device 1 via the switch 12 for switching between ON / OFF and the terminal 11 of the control device 1, rectified into a DC voltage by the diode bridge 5, smoothed by the electrolytic capacitor 6, and then input to the control power supply generation unit 7. To be done. In addition, the AC power supply 4 is applied to the inside of the control device 1 via the electromagnetic switch 14 that opens when the electric motor 2 is stopped in an emergency, smoothed by the electrolytic capacitor 9, and then input to the inverter unit 10. Between the diode bridge 8 and the electrolytic capacitor 9, a DC reactor 16 for reducing the harmonic component of the current supplied to the electrolytic capacitor 9 can be connected to the outside of the control device 1 by the terminal 15.

In the above structure, when some trouble occurs in the machine using the electric motor 2 and the electric motor 2 is brought to an emergency stop, the electromagnetic switch 14 is opened to shut off the power source of the electric motor 2. Since the power source 3 continues to supply power to the control power source generator 7, the control circuit inside the control device 1 can continue to operate. Further, after the emergency stop of the electric motor 2, the control circuit on the machine side continues to operate. Thus, the control circuit on the machine side can know whether or not the control device 1 was normal after the emergency stop of the electric motor 2 when the electric motor 2 has a malfunction leading to the emergency stop. That is, it is possible to know whether the cause of the emergency stop is the machine side or the electric motor side including the control device, and if the control device 1 of the electric motor 2 has a cause, the failure content can be grasped.

[0005]

In the above-described conventional motor control device, since two alternating-current power supplies are connected by wiring, the number of wirings is large and the number of terminals to be connected is also large. Furthermore, the size of the control device cannot be reduced because two diode bridges for rectifying the AC voltage into the DC voltage are required in the control device.

The present invention has been made to solve the above problems, and an object of the present invention is to reduce the number of terminals and simplify the size of the control device by simplifying the wiring connection of the control device of the electric motor.

[0007]

To solve this problem, the present invention rectifies a first terminal for connecting an AC power supply of one system and an AC power supply input from the first terminal into a DC voltage. Control to generate a control power by smoothing the diode bridge and the second terminal that connects the electromagnetic switch that opens when the machine using the electric motor is stopped in an emergency, and the first electrolytic capacitor to the output of the diode bridge. A power supply generation unit, an inverter unit that generates an AC voltage applied to the electric motor, and is connected in parallel to the input of the inverter unit,
And a second electrolytic capacitor that connects one terminal to the output of the diode bridge, and one of the second terminals that connects the electromagnetic switch is connected to the inverter section of the output of the diode bridge. A non-terminal is connected, and a terminal of the input of the inverter section that is not connected to the diode bridge is connected to the remaining one of the second terminals. In addition, an electromagnetic switch that opens when the machine that uses an electric motor is stopped in an emergency and a DC reactor that reduces harmonic components of the current that flows into the control device can be connected in series to the second terminal. is there.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention rectifies a first terminal for connecting an alternating-current power supply of one system and an alternating-current power supply input from the first terminal to a direct-current voltage. A control power supply that generates a control power by smoothing the output of the diode bridge and the electromagnetic switch that opens when a machine using an electric motor is stopped in an emergency with the first electrolytic capacitor. With the generation part,
An inverter unit that generates an AC voltage to be applied to the electric motor,
The diode bridge is connected to the input of the inverter unit in parallel, and includes a second electrolytic capacitor that connects one terminal to the output of the diode bridge, and the diode bridge is connected to one of the second terminals to which an electromagnetic switch is connected. Of the output of the inverter unit is connected to the non-connected terminal, and the remaining one of the second terminal is connected to a terminal of the input of the inverter unit not connected to the diode bridge This is a device, and by connecting a single-system AC power supply by wiring, the operation of the control power supply inside the control device can be continued even if the power source of the electric motor is cut off.

According to a second aspect of the present invention, the second terminal for connecting the electromagnetic switch which is opened when the machine using the electric motor is brought to an emergency stop is a DC for reducing the harmonic component of the current flowing into the control device. A terminal for connecting a reactor and an electromagnetic switch connected in series, which is a terminal for connecting a motor, wherein a DC reactor can be attached and a current flowing into the second electrolytic capacitor. It has the effect of reducing the harmonic components of.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. FIG. 1 is a circuit diagram of a motor control device according to an embodiment of the present invention.

Referring to FIG. 1, a control device 21 for the electric motor 22.
Has a first terminal 24 to which an AC power supply 30 is connected and a second terminal 23 to which an electromagnetic switch 33 that opens when the electric motor 22 is to be emergency stopped is connected. The AC power supply 30 is applied to the inside of the control device 21 via a switch 31 for switching ON / OFF of the control device 21 and the first terminal 24,
The inverter unit 2 that generates an AC voltage to be applied to the electric motor 22 after being rectified into a DC voltage by the diode bridge 25.
9 and the control power supply 27 that generates the control power to operate the control device 21. The first electrolytic capacitor 26 smoothes the output of the diode bridge 25 and supplies power to the control power generation unit 27. The second electrolytic capacitor 28 smoothes the output of the diode bridge 25 and supplies power to the inverter unit 29. Between the output of the diode bridge 25 and the second electrolytic capacitor 28, an electromagnetic switch 33, which is opened when the electric motor 22 is to be emergency stopped, is connected to the outside of the control device 21 via the second terminal 23.

Further, when it is necessary to reduce the harmonic component of the current supplied to the second electrolytic capacitor 28, the DC reactor 32 can be connected to the second terminal 23 by electromagnetic switching without providing a new external terminal. The device 33 and the DC reactor 32 can be externally connected in series.

Explaining the operation of the above configuration, the control power supply generating unit 27 inside the control device 21 is constituted by the switch 3
The operation is continued while 1 is ON (closed). When the switch 31 is ON and the electromagnetic switch 33 is closed, the power source of the electric motor 22 is supplied to the inverter unit 29, and when the electromagnetic switch 33 is opened, the power source of the electric motor 22 to the inverter unit 29 is cut off.

The first terminal and the second terminal are, for example, a terminal block and a connector, and the first terminal and the second terminal may be a combination of the terminal block and the connector. Further, if it is configured with one terminal block or one connector, the control device can be further downsized.

[0015]

As described above, according to the present invention, by connecting the AC power supply of one system by wiring, the operation of the control power supply inside the control device can be continued even if the power source of the electric motor is shut off. Therefore, it is possible to reduce the number of wires of the AC power supply and the number of terminals. In addition, 2 to 1 diode bridges
Since the number can be reduced to one, the control device can be downsized.

Further, the DC reactor can be attached without providing a new external terminal, and both specifications of the presence or absence of the DC reactor can be configured only with the same second terminal, so that the wiring connection can be simplified. And downsizing of the control device becomes possible.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a motor control device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a conventional motor control device.

[Explanation of symbols]

 1, 21 Control device 2, 22 Electric motor 3, 4, 30 AC power supply 5, 8, 25 Diode bridge 6, 26 First electrolytic capacitor 7, 27 Control power generation unit 9, 28 Second electrolytic capacitor 10, 29 Inverter Part 11 Terminal 12,31 Switch 13,24 First terminal 14,33 Electromagnetic switch 15,23 Second terminal 16,32 DC reactor

Claims (2)

[Claims] 1. A first terminal for connecting an AC power supply of one system, a diode bridge for rectifying the AC power input from the first terminal to a DC voltage, and an emergency stop for a machine using a motor. A second terminal that connects an electromagnetic switch that opens to the control circuit, a control power supply generation unit that smoothes the output of the diode bridge with a first electrolytic capacitor, and a control power supply, and an inverter that generates an AC voltage applied to the electric motor Section, and is connected in parallel to the input of the inverter section,
And a second electrolytic capacitor that connects one terminal to the output of the diode bridge, and one of the second terminals that connects the electromagnetic switch is connected to the inverter section of the output of the diode bridge. A control device for an electric motor, wherein a non-terminal is connected, and a terminal of the input of the inverter section which is not connected to the diode bridge is connected to the remaining one of the second terminals. 2. A second terminal for connecting an electromagnetic switch which is opened when an electric motor-driven machine is brought to an emergency stop is provided with a DC reactor and an electromagnetic switch for reducing a harmonic component of a current flowing into a control device. The electric motor control device according to claim 1, wherein the control device is a terminal for connecting those connected in series.