7th International Conference on Electric Power Equipment– Switching Technology (ICEPE 2024)

226 / 2024-05-19 21:39:50

Asynchronous control method for large-capacity generator circuit breaker with vacuum multi-breakers in parallel

generator circuit breaker,vacuum multi-breakers in parallel,current-sharing,asynchronous control,large-capacity breaking

An environmentally friendly generator circuit Breaker (GCB) is a key power switch equipment in power plants, which has the advantages of being completely environmentally friendly, fast action, and low cost. It is crucial for the safe and stable operation of generators and power grid systems. A single commercial vacuum interrupter (VI) can not meet the working requirements of large-capacity GCB, and the vacuum multi-breakers in parallel can effectively improve the rated current flow capacity and short-circuit opening capacity. However, due to the actual production process, environmental magnetic interference, and other reasons, it is difficult to balance the current distribution of each parallel branch. The problem can be divided into two parts: static current-sharing and dynamic current-sharing. Firstly, the paper carried out an experimental study on the dispersion of the opening time of the VI. It can be found with the increase of the voltage level of the precharge capacitor, the dispersion will gradually decrease and remain at a low level, which was conducive to the accurate control of the opening time of the VI. When the vacuum arc was generated, the current transfer process based on the arc voltage drive was analyzed in detail, and an innovative asynchronous control method of vacuum multi-breakers in parallel was proposed. The parallel current-sharing experiment of vacuum double breakers was carried out. The experiments showed that the proposed method could cleverly use current transfer to offset the influence of static current imbalance, reduce the current difference, and significantly improve the dynamic current-sharing effect. The conclusions will lay the foundation for improving the breaking performance of the high-voltage and large-capacity GCB.