铁心异常时基于异频电流激励法的定子铁心损耗试验分析

为防止发电机在运行中因片间绝缘损坏，造成短路，引起局部过热，甚至危及机组的安全运行，需要对发电机的定子铁心进行损耗试验。对于试验方案在进行大型机组试验时存在绕线困难等问题，提出了一种采用异频电流激励法进行发电机定子铁心损耗试验的方法。建立铁心存在短路缺陷情况下的有限元仿真模型，通过对比工频大电流激励和异频小电流激励下铁心的发热情况，论证了异频小电流可以替代工频大电流进行铁心损耗试验。

Stator Core Loss Test Analysis Based on Different Frequency Current Excitation Method Under Abnormal Iron Core Condition

Due to the damage of insulation between blades during operation, a short circuit may occur in the generator, causing local overheating, and even endangering the safe operation of the unit. It is necessary to conduct a loss test on the stator core of the generator. The current test scheme has problems such as difficulty in winding when conducting the large-scale unit tests. A method of using the different frequency current excitation method to test the loss of the stator iron core of the generator is proposed. The finite element simulation model of the iron core with short-circuit defects is established. By comparing the heating conditions of the iron core under the conditions of power frequency large current excitation and different frequency small current excitation, it is demonstrated that different frequency small current can replace the power frequency large current to carry out iron core loss test.