具备自适应重合闸能力的电容箝位式直流断路器

Capacitor-clamping DC Circuit Breaker With Adaptive Reclosing Capability

为了解决直流电网直流故障线路切除及重合闸问题,提出了一种具备自适应重合闸能力的电容箝位式直流断路器。该方案采用耐压、耐流能力强且价格低廉的晶闸管作为主要开关器件,利用电容箝位模块主动升压,起到高电压支撑作用,迫使换流器出口故障电流快速下降至零,然后通流模块自然关断从而隔离故障线路。并且该方案利用自适应重合闸判断模块的电流值实现故障类型自判断,防止重合闸于永久性故障对电力系统造成二次冲击。最后,利用PSCAD/EMTDC仿真验证所提方案的有效性,并从器件使用量和自适应重合闸能力等方面验证了论文方案优异的综合性能。

In order to solve the problems like DC fault line isolation or reclosing in DC grid, a capacitor-clamping DC circuit breaker with adaptive reclosing capability is proposed.The thyristors with high-voltage and high-current resistances at a low price are used as the main switching devices. The capacitor-clamping module is used to boost the voltage actively,which can play a role of voltage support, forcing the fault current to drop to zero quickly. Besides, the temporary and permanent fault can be distinguished by analyzing the current of the adaptive reclosing judgment module, which can prevent reclosing in permanent fault from causing damage to the stability of the power system. At last, a simulation on the PSCAD/EMTDC platform is used to verify the effectiveness and applicability of this scheme, and the excellent comprehensive performance of the proposed scheme is verified in terms of the usage of the devices and the adaptive reclosing capability.