Method for controlling power switching apparatus

Patent metadata

Field	Value
Publication number	US-9959999-B2
Application number	US-201615176869-A
Country	US
Kind code	B2
Filing date	Jun 8, 2016
Priority date	Jun 9, 2015
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A method for controlling a power switching apparatus to solve problems including: setting a target time reaching a predetermined position immediately before a target phase by a time calculator during an opening and closing operation of a movable arc contact with respect to a fixed arc contact in a target phase at a predetermined average switching speed; and controlling an electric motor at a speed equal to or less than an average switching speed immediately before the target phase from an operation start time to the target time by a motor controller.

First claim

What is claimed is:

1. A method for controlling a power switching apparatus including a sealed tank that is filled with insulating gas, a breaking portion that is configured of a fixed arc contact provided in a fixed-side conductor disposed within the sealed tank and a movable arc contact coming into contact (pole closing) or separating (pole opening) with or from the fixed arc contact and provided in a movable-side conductor, an electric motor that generates a driving force for operating the movable arc contact, a drive circuit that drives the electric motor, a position detecting device that detects a position of an electric motor mover of the electric motor, a controller that controls at least one of a voltage, a current, and a phase supplied to the electric motor based on position information of the electric motor mover detected by the position detecting device,
wherein the controller includes a phase analysis portion that accumulates a time column of a current or a voltage of a circuit network from a current and voltage monitor detecting the voltage or the current of the circuit network from a predetermined time to a current time, and analyzes at least the phase, a time calculator that calculates a target time, and a motor controller that controls the electric motor via the drive circuit, the method for controlling a power switching apparatus comprising:
setting a target time (Ts) reaching a predetermined position (Xs) immediately before a target phase by the time calculator during an opening and closing operation of the movable arc contact with respect to the fixed arc contact in the target phase at a predetermined average switching speed; and
controlling the electric motor at a speed equal to or less than the average switching speed immediately before the target phase from an operation start time (T 0 ) to the target time (Ts) by the motor controller.

2. The method for controlling a power switching apparatus according to claim 1 ,
wherein the drive circuit receives a control signal from the motor controller, performs switching of internal elements as indicated by the signal and supplies a current from a power supply to the electric motor, the position detecting device grasps a position of the electric motor mover by reading a position of an electric scale by a sensor attached to the electric motor mover and transmits the position information of the electric motor mover to the motor controller, and the motor controller executes speed control based on the position information.

3. The method for controlling a power switching apparatus according to claim 2 ,
wherein a motor current sensor is provided in the drive circuit and a motor current value detected by the motor current sensor is transmitted to the motor controller and the electric motor is controlled.

4. The method for controlling a power switching apparatus according to claim 1 ,
wherein the control method performs a first step in which a switching operation start command is output from a command portion to the time calculator, a second step in which the current and voltage monitor detects information about the circuit network and the position detecting device detects a position (XR) of the electric motor mover, a third step in which the position detecting device always monitors the XR detected in the second step and then the time calculator calculates the target phase and the target time (Ts) immediately before a target operation from information of the circuit network, and a speed (V) determined from the predetermined position (Xs) immediately before the target phase, a fourth step in which a motor current value (J 1 ) realizing the speed (V) calculated in the third step is output to the motor controller, a fifth step in which the motor current value (J 1 ) is compared to a limit motor current value (Jmax), a sixth step in which if J 1 >Jmax in the fifth step, the target phase is changed to a target phase of the next time and the target time (Ts) is calculated, a seventh step in which if J 1 <Jmax in the fifth step, a current position (XR) of the electric motor mover is compared to the predetermined position (Xs), an eighth step in which if it is not XR>Xs in the seventh step, the process returns to the fourth step and if XR>Xs in the seventh step, the drive circuit is driven so that the speed is a switching speed (V 1 ), a ninth step in which the XR is compared to a pole opening and pole closing position (Xt), and a tenth step in which if it is not XR≥Xt in the ninth step, the process returns to the eighth step and if XR≥Xt in the ninth step, the speed (V) is controlled to be 0.

5. The method for controlling a power switching apparatus according to claim 1 ,
wherein the electric motor mover is moved at an initial speed V 0 =(Xs−X 0 )/(Ts−T 0 ) from a switching operation start position (X 0 ) to the predetermined position (Xs) reaching the target time (Ts) when a current time is T 0 and is operated at the predetermined switching speed (V 1 ) from the predetermined position (Xs) to the pole opening and pole closing position.

6. The method for controlling a power switching apparatus according to claim 1 ,
wherein the target time (Ts) reaching the predetermined position (Xs) immediately before the target phase is set to a time within ¼ period immediately before the target phase.

7. The method for controlling a power switching apparatus according to claim 1 ,
wherein if the motor current value exceeds the limit motor current value within a time until the target time after the switching operation is started, the target phase is delayed by at least a half period and the target phase and the target time (Ts) reaching the predetermined position immediately before the target phase are recalculated.

8. The method for controlling a power switching apparatus according to claim 1 ,
wherein the speed (V 0 ) from the switching operation start position (X 0 ) to the predetermined position (Xs) causes the electric motor mover to be controlled in a constant acceleration at equal to or less than the limit motor current value.

Assignees

• Hitachi Ltd

Inventors

• Adachi Koichiro
• Urai Hajime
• Shiraishi Katsuhiko
• Sasaki Masataka

Classifications

• H01H2003/268

  using a linear motor · CPC title

• H01H33/593 Primary

  for ensuring operation of the switch at a predetermined point of the AC cycle (for multipolar switches H01H9/563) · CPC title

• H01H11/0062

  Testing or measuring non-electrical properties of switches, e.g. contact velocity (monitoring contacts H01H1/0015; monitoring gas density H01H33/563; monitoring vacuum H01H33/668; calibrating H01H69/01; adjusting H01H71/74; testing of electrical properties G01R31/333) · CPC title

• H01H33/36

  using dynamo-electric motor · CPC title