Abstract:

Abstract:Starting from the angle of power transformer economical operation, the selection of the economical operaton point of the transformer and the adjustment strategy of the transformer operation mode were analyzed.The implementation of economical operation needs to switch the transformer frequently. The excitation surge current of the transformer during switch on without load has some negative effects for the transformer service life and the safety, efficiency and reliability of the power supply. In order to eleminate these negative effects, a excitation surge current suppression method based on phase selecting switch on was proposed, and the method can reduce the excitation surge current. The superiority of the method was verified by PSCAD/EMTDC simulation and power system dynamic simulation test.

Key words: Keywords:transformer, economical operation, excitation surge current, suppression technique