发电机空气间隙对横差电流的影响

Impact of Generator Air Gap on Transverse Differential Current

通常,发电机定子绕组或转子绕组匝间短路是导致横差保护动作的主要原因。但是,如果机组检修后,定、转子间的空气间隙偏差过大,也会使横差电流超过设定值,导致横差保护动作。根据以往的案例,着重分析了在发电机启励、空载、灭磁过程中空气间隙对定子横差电流的影响。

Usually,the motion of generator transverse differential protection is mainly caused by the turn-to-turn fault on the stator windings or on the rotor windings.But,after the repair,if the difference among all air gaps between the stator and the rotor is too large,it also can make the transverse differential current exceed the setting value which will cause the motion of transverse differential protection.Based on a case,the impacts of air gap on the transverse differential current of stator in the course of generator startup,no-load operation and excitation suppression are analyzed.