Cancellation of Closing Resistance of Extra-High Voltage Circuit Breaker in Hydro-power Station and Analysis of Closing Over-voltage in Alternatives

Although the addition of closing resistance to extra-high voltage Circuit breaker can effectively inhibit closing over-voltage, the existence of closing resistance also reduces the reliability of circuit breaker and increases the equipment investment cost. Therefore, it is important to cancel the closing resistance of high voltage circuit breaker for the determination of electrical design scheme of hydro-power station. Here, based on the simulation analysis of closing overvoltage of extra-high voltage Circuit Breaker in several hydropower projects, an alternative scheme of canceling the closing resistance of extra-high voltage Circuit Breaker in hydropower projects is given, which improves the reliability and economy of hydro-power projects.