A No-Arc DC Circuit Breaker Based on Zero-Current Interruption

2017 2nd Asia Conference on Power and Electrical Engineering

能源学;电工学

Xiang, Xuewei^1 ; Chai, Jianyun^1 ; Sun, Xudong^1

Tsinghua University, Beijing

100084, China^1

关键词: Buffering effect;    Current limiting;    Dc circuit breakers;    DC power supplies;    Insulating strength;    Mechanical switch;    Resonance circuits;    Short-circuit fault;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/199/1/012079/pdf
DOI  :  10.1088/1757-899X/199/1/012079

来源: IOP

【 摘 要 】

A dc system has no natural current zero-crossing point, so a dc arc is more difficult to extinguish than an ac arc. In order to effectively solve the problem of the dc arc, this paper proposes a dc circuit breaker (DCCB) capable of implementing a no-arc interruption. The proposed DCCB includes a main branch consisting of a mechanical switch, a diode and a current-limiting inductor, a semi-period resonance circuit consisting of a diode, an inductor and a capacitor, and a buffer branch consisting of a capacitor, a thyristor and a resistor. The mechanical switch is opened in a zero-current state, and the overvoltage caused by the counter electromotive force of the inductor does not exist. Meanwhile, the capacitor has a buffering effect on the voltage. The rising of the voltage of the mechanical switch is slower than the rising of the insulating strength of a contact gap of the mechanical switch, resulting in the contact gap not able to be broken down. Thus, the arc cannot be generated. The simulation results show that the proposed DCCB does not generate the arc in the interruption process, the rise rate of the short circuit current can be effectively limited, and the short circuit fault point can be rapidly isolated from the dc power supply.