Abstract: The inter-turn stator winding fault of synchronous generator, which is common and destructive, greatly affects the security of the generator and the power network. Based on the extended Park vector approach(EPVA), a practical method of reference frame conversion—the extended alpha beta method, was proposed, and the unsymmetric voltage and current caused by the inter-turn stator winding fault in generator was analyzed by this new method. Then the graphical representation and digital characteristic of fault is obtained. This method is reliable and easy to be applied into practice. And it is a noninvasive approach to detect the inter-turn stator winding fault. The dynamic simulative experiment results with different load, demonstrate the effectiveness of the proposed technique. Combined with multi-loop method, this can be applied to the on-line detection and location of inter-turn short circuits in the stator windings of three-phase synchronous generator as a new method. 

Key words: Synchronous generator, Dynamic simulative experiment, Stator winding faults, Extended alpha beta reference frame conversion, Multi-loop

摘要： 同步发电机定子绕组匝间短路故障是一种常见的、破坏性很强的故障，对电厂发电机乃至电网的安全运行都将带来一系列严重的影响。参考扩展Park矢量方法（EPVA），利用实用的alpha beta 0坐标，结合EPVA矢量分析方法对发电机定子绕组内部匝间短路故障引起的不对称电压电流信号进行了分析研究，得到该类故障特征的直观图形和数字特征表示。该方法可靠、简单易行，使用该方法可以实现发电机定子绕组内部故障的非侵入式检测，不同负载下的动模试验分析证明了该方法的有效性。结合多回路方法，该方法可以作为三相同步发电机内部匝间短路在线检测和故障定位的新方法。

关键词: 同步发电机, 动模试验, 定子绕组故障, 扩展alpha beta 坐标变换, 多回路