Control Circuit Optimization for High-speed Circuit Breaker in Traction System of Jinan Metro Line 3

Abstract

[Objective] In the early operation stage of Jinan Metro Line 3, multiple sporadic high-speed circuit breaker closing failures are reported. To improve the reliability of train operation, it is necessary to optimize the high-speed circuit breaker control circuit in the traction system. [Method] According to the relevant closing command and the component status when a closure failure of the high-speed circuit breaker on Line 3 train occurs, and in accordance with the control logic principle of the high-speed breaker, the causes of the occasional closure failure are analyzed and the optimization measures are put forward. [Result & Conclusion] The causes of the occasional closure failure are that in the process of closure control of high-speed circuit breaker, the induced electromotive force generated at both ends of the high-speed circuit breaker coil makes the closing power insufficient, resulting in the failure closure of the breaker. The improvement measure is to connect freewheel diodes at both ends of the high-speed circuit coil to suppress the induced electromotive force generated by the above coil. With the above improvement measure, the closure failure of the high-speed circuit breaker caused by induced electromotive force never occurs again, and the reliability of train operation is effectively improved.

Keywords

• metro
• traction system
• high-speed circuit breaker
• control circuit