[关键词]
[摘要]
以1台300 MW同步发电机为例,考虑了阻尼系统,在不对称运行条件下,研究了励磁绕组匝间短路后发电机的相关故障特征量,包括励磁电流、励磁绕组的感应电动势、被短路的励磁回路电流以及阻尼绕组电流等。在此基础上研究了负序磁场中励磁短路线圈的匝数、节距以及短路点过渡电阻等因素对励磁短路电流的影响,并粗略地计算了短路点的发热量。研究结果可为发电机经历恶劣工况后的励磁匝间短路故障的维修提供可靠的决策支持。
[Key word]
[Abstract]
The rotor windings interturn short circuit fault is one of the common faults in turbine generator. When a generator runs in asymmetric condition emerging negative sequence magnetic field, the deterioration rate of interturn short circuit fault in rotor windings can be accelerated. In this paper, a 300 MW turbine generator running under asymmetric operation was studied as an example. Considering damping system, the variations of generator fault characteristics after rotor winding interturn short circuit were studied, including rotor current, rotor winding induced electromotive force, short circuit loop current and damping current. What’s more, the influences of rotor short circuit coil turns and pitch and shortcircuit point transition resistance under negative sequence magnetic field on the rotor short current were studied, also the heating condition of the short circuit point was roughly analyzed. The results provided a reliable decision support for repairing interturn short circuit in rotor winding after a generator experienced bad operating conditions.
[中图分类号]
TM 31
[基金项目]
河北省自然科学基金项目(E2016502031);中央高校基本科研业务费专项资金项目(2017MS106)