Method and device for controlling at least one circuit breaker of a power system
AssigneeHitachi Energy Switzerland AG
InventorsMichael Stanek, Soumya Kanta
Life of this patent
Estimating the term…
Abstract
A power system comprises a power source, a transmission line coupled to the power source through a circuit breaker, a shunt reactor coupled to the transmission line, and a current transformer connected in series with the shunt reactor. A method for controlling the circuit breaker of the power system comprises processing an output signal of the current transformer to obtain the voltage on the transmission line by determining a time derivative of a current sensed by the current transformer. The method further comprises performing, by at least one control or protection device, a control or protection operation (e.g., auto-reclosing) based on the determined time derivative of the current sensed by the current transformer.
Claims17
A method of controlling at least one circuit breaker of a power system, the power system further comprising a power source, a transmission line, and a voltage transformer connected to the power source and adapted to sense a source voltage of the power source, the at least one circuit breaker connected in series between the power source and the transmission line, a shunt reactor, and a current transformer connected in series between the transmission line and the shunt reactor to measure a current through the shunt reactor, the method comprising:
- processing an output signal of the current transformer comprising determining a time derivative of a current sensed by the current transformer;
- and
- performing a control operation on the at least one circuit breaker based on the determined time derivative of the current sensed by the current transformer, the control operation comprising a controlled reclosing of the circuit breaker after tripping of the circuit breaker based on an output signal of the voltage transformer and on the time derivative of the current sensed by the current transformer.
A control device for controlling at least one circuit breaker of a power system, the power system further comprising a power source, a transmission line, and a voltage transformer connected to the power source and adapted to sense a source voltage of the power source, the at least one circuit breaker connected in series between the power source and the transmission line, a shunt reactor, and a current transformer connected in series between the transmission line and the shunt reactor,
- the control or protection device comprising:
- an input to receive an input signal representing a current sensed by the current transformer;
- and
- a control circuit adapted to perform a control operation on the at least one circuit breaker based on a time derivative of the current sensed by the current transformer, the control operation comprising a controlled reclosing of the circuit breaker after tripping of the circuit breaker based on an output signal of the voltage transformer and on a line voltage signal derived from the time derivative of the current sensed by the current transformer.
A power system comprising:
- a power source;
- a transmission line;
- at least one circuit breaker connected in series between the power source and the transmission line;
- transmission line;
- a shunt reactor coupled to the transmission line;
- and
- a current transformer connected in series between the transmission line and the shunt reactor to measure a current through the shunt reactor;
- a voltage transformer connected to the power source and adapted to sense a source voltage of the power source;
- and
- a control device connected to the current transformer, the control device configured to:
- process an output signal of the current transformer comprising determining a time derivative of a current sensed by the current transformer;
- and
- perform a control operation on the at least one circuit breaker based on the determined time derivative of the current sensed by the current transformer, the control operation comprising a controlled reclosing of the circuit breaker after tripping of the circuit breaker based on an output signal of the voltage transformer and on the time derivative of the current sensed by the current transformer.
Dependencies are inferred from the claim text.