为实现对发电机励磁绕组匝间短路故障的在线检测与保护,以一台12kW、3对极隐极同步发电机为例,采用多回路法对该样机负载运行时发生的励磁绕组匝间短路故障进行计算,并与实验进行了对比分析;基于计算与实验结果,分别探讨了分布式励磁绕组的故障位置及短路匝数对故障特征量的影响;在此基础上,提出利用定子分支谐波电流进行故障定位及短路匝数估算的新方法,为隐极发电机励磁绕组匝间短路故障在线检测与保护方案设计奠定了理论基础。
In order to realize the on-line detection and protection of the field winding inter-turn short circuit faults in synchronous generator, in this paper, the field winding inter-turn short circuit faults of a 12kW non-salient-pole synchronous generator with three pairs on load were calculated by the multi-loop method, the result of which was analyzed comparatively with the corresponding experiment. The influences of distributed field winding fault position and short circuit turns to the fault characteristic quantities were respectively discussed. On the basis, a new method of fault slots judgment anti short circuit turns estimation based on stator branch harmonic current was proposed. This paper firstly made a deep and systematical analysis to the fault law of distributed field winding inter-turn short circuit, laying a foundation for the inter-turn short circuit fault on-line detection and protection of the field windings in non-salient-pole generator.