基于电流波形差异性的超导电缆失超保护策略

Quench Protection Strategy of Superconducting Cable Based on Current Waveform Difference

针对高温超导电缆失超运行工况难以准确快速检测,失超过程中发生轻微故障差动保护难于及时反应的问题,提出了失超综合保护策略。利用超导电缆简化数据模型推导出超导态运行时屏蔽层电流相对于超导层的补偿系数,计算出电缆失超时电流波形的差异度,提出基于电流波形差异性和非电气量的失超综合保护策略,并利用PSCAD建立反应超导态、失超态连续变化的超导电缆失超模型,对提出的保护策略进行了仿真研究,仿真验证了失超综合保护策略的可行性。

Aiming at the problem that it is difficult to accurately and quickly detect the operation condition of hightemperature superconducting cable when it is out of normal state,and it is difficult for the differential protection to respond in time when a slight fault occurs in the process of overload,this paper proposes a comprehensive protection strategy for overload.Based on the simplified model of superconducting cable,the compensation coefficient of shield layer current relative to conducting layer current is deduced.The difference degree of current waveform is calculated at the condition of cable loss time-out.The comprehensive protection strategy is proposed based on current waveform difference and non-electric quantity.PSCAD is used to build the loss time-out model of superconducting cable,which reflects the continuous change of superconducting and quenching state.The simulation results show that the comprehensive protection strategy is feasible.