FU Bing1,2, XIE Zhen hua2

(1.College of Mechanical and Electrical Engineering， China Jiliang University, Hangzhou 310015， China；

2.Quality Low Voltage Apparatus Research Institute，Zhejiang Testing & Inspection Institute for

Mechanical and Electrical Products, Hangzhou 310051， China)

Abstract: Aiming at resolving the problem of poor performance against lightning surge and automatic reclosing function’s failure to the residual current circuit breaker in the grid, automatic reclosing signal sampling circuits of residual current circuit breaker were analyzed, the performance of three residual current circuit breakers with reclosing signal sampling circuits of voltage, current and machine type were compared by electromagnetic compatibility surge and simulation grid voltage drop test. Improvement measures were put forward to solve the disadvantages in voltage and current type of automatic reclosing signal sampling circuits, and the improved ones were retested. The results indicate that the residual current circuit breakers with voltage type automatic reclosing signal sampling circuit have poor performance against lightning surge and be easily failed in automatic reclosing, and the ones with current or machine type have the better performance, particularly, the machine type automatic reclosing signal sampling circuit is worth a recommendation to manufacturing enterprises which has lower cost and a higher value of practical application.

Key words: auto reclosing; sampling circuit; surge; voltage drop