CAJ | 학술논문

针对双极柔性直流输电系统站内接地故障，对其故障机理及故障特性进行研究，推导故障分量的数学表达式。分析结果表明，故障发生后交流电流会出现直流偏置导致交流断路器无法正常断开，并且故障站子模块持续充电导致子模块严重过压。针对上述情况，制定相应的保护控制策略，并通过仿真结果验证了相关理论计算及控制保护策略的正确性。
침대쌍겁유성직류수전계통참내접지고장，대기고장궤리급고장특성진행연구，추도고장분량적수학표체식。분석결과표명，고장발생후교류전류회출현직류편치도치교류단로기무법정상단개，병차고장참자모괴지속충전도치자모괴엄중과압。침대상술정황，제정상응적보호공제책략，병통과방진결과험증료상관이론계산급공제보호책략적정학성。
In view of converter grounding fault of bipolar flexible high voltage direct current (HVDC) transmission system, fault mechanisms and fault characteristics were studied, and mathematic expression of fault components were derived. Analysis results show that the AC fault current contains DC bias leading to the AC breaker cannot disconnect properly and the DC fault current continuously charge the sub-module leading to the sub-module overvoltage seriously. According to the aforementioned situation, control and protection schemes were developed. The simulation results demonstrate the relevant analysis is precise and the protection scheme is validity.