大型同步发电机单相接地故障的暂态多回路分析——实验验证

Transient multi-loop analysis on the stator ground fault of large synchronous generator ——Experimental verification

为准确仿真大型同步发电机定子单相接地故障,提出了暂态多回路模型,该模型将定子绕组划分成多个单元,将定子绕组对地分布电容等效为准分布参数的电容。为验证仿真的正确性和有效性,对一台12kW同步发电机实验样机进行了单机空载、中性点电阻接地情况下的定子单相接地实验,并给出了实验结果。对比发电机机端三相电压、中性点电压的仿真结果与实验结果,各电压的绝对偏差不超过电压幅值的7.0%,验证了采用准分布电容参数的定子单相接地的多回路暂态模型的准确性和有效性。

Stator ground faults of large synchronous generators were analyzed with a transient model based on the multiloop method. This model partitions the stator windings into many unit circuits and considers the distributed capacitances of the stator windings to the ground as quasidistributed capacitances. The simulations were compared with experimental results for a ground fault in the stator windings of a 12 kW synchronous test generator as a single machine with no load and neutral grounding with a resistor. The simulation results for the voltages of the threephases terminals and the neutral were within 7.0% of the experimentally measured voltages. The transient multiloop model, therefore, provides an excellent way stator ground faults.