محمد يارمحمدي

Capacitor bank energization in a high voltage network is likely to impose transients causing notable problems not only for the capacitor itself, but also the other components such as, the circuit breaker, and electrical apparatuses available on the network; as a result there have been various methods to address this issue. In this paper, controlled switching method is regarded for switching both grounded and ungrounded capacitor banks. There are two main subjects in this paper, the first one is the impact of spread time on controlled switching by two unit circuit breakers, and the latter is to find out the best way for calculating target point on controlled switching for ungrounded capacitor banks using non-ideal circuit breakers. The concept of controlled switching of circuit breakers deals with how to closing the circuit breaker and control the moment of sending closing command, regarding the voltage wave across circuit breaker's contacts, that the presence of current after closing do not cause problematic transients. Target point is eva‎luated for both single and two-unit circuit breakers through mathematical equations, the latter of which is an innovation. In addition to this, there is a non-ideal circuit breaker model designed on EMTP-RV software for both grounded and ungrounded capacitor banks. Likewise, the controller model for energizing a grounded capacitor bank is designed. The employed network for simulation is one used to analyze capacitor switching transients on Hydro Quebec network and there is a transient model for all components of the network, due to the existence of high voltage network. References have mentioned various ways of controlled closing of ungrounded capacitor banks, all of them are analyzed, plus their advantages and disadvantages are discussed. Meanwhile, one method that provides better results is chosen and improved.

برق‌دار كردن كنترل شده , برق‌دار كردن بانك‌هاي خازني , كليدهاي چند محفظه اي , كليد غير ايده‌آل

Controlled Closing , Capacitor Bank Energization , Multi-chamber Circuit breakers , Non-ideal Circuit Breaker

Mohammad Yarmohammadi

Seyyed Mohammad Shahrtash