【摘要】 通过计算机数值仿真和动模实验及理论分析,研究了分别选取线路电流i和电容电压uc两种不同的同步信号时对可控串补(TCSC)装置在系统发生单相接地短路故障时的影响。以线路电流i作为同步信号易使单相接地短路故障时线路电流出现严重直流分量和严重扭曲现象;以电容电压uc作为同步信号时,故障后系统中未出现明显直流分量,但出现明显的低次谐波。采用线路电流的基波分量作为TCSC的同步信号较为合适,其优点是消除了同步信号中的直流分量和谐波分量,使同步信号相位起点不发生偏移,可使系统稳定运行。提出了有效控制对策,缩短了故障时的调节时间,消除了故障时的不良影响,提高了系统的暂态稳定控制特性。更多还原

【Abstract】 When the single phase to grounding fault occurs, the respective influence of two different synchronizing signals, i.e., the line current i and capacitor voltage uc, on TCSC device are studied by the digital simulation, dynamic simulation and theoretical analysis. Taking the line current i as synchronizing signal, the serious DC component will appear in line current i and the line current i will be seriously distorted when single phase grounding fault occurs. Taking the capacitor voltage uc as synchronizing signal, there is not serious DC component in the power system, but serious low-order harmonics. So both the line current and the capacitor voltage are not suitable for being used as the synchronizing signal. It is more rational to take the fundamental component of the line current for being used as the synchronizing signal of TCSC. The advantage of this method is to eliminate the DC component and harmonic components and the starting point of the phase angle of the synchronizing signal will not be shifted, and it is helpful for the stable operation of the power system. In this paper an efficient control strategy is proposed and this strategy can reduce the adjusting time during the fault process and reduce the harmful effect from the fault and improve the control characteristics of power system transient stability.更多还原