Research on overvoltage suppression of interrupting no load transformer

Abstract

In the process of power system operation, it is normal to interrupt no load transformer, reactor and no load motor. Switching those inductive loads will give rise to high amplitude overvoltage. With the example of a steel mill's refining furnace transformer, this paper covers the basic principle of the overvoltage formation, introduces the advantages and disadvantages of the resistance-capacitance absorbing device and rectifier bridge device. On base of the above analysis, this paper puts forward a mixed device to suppress overvoltage of interrupting no load transformer. Moreover, simulation has been worked with ATP-EMTP, the results show that the device can greatly reduce the overvoltage and improve the reliability of the system. At last, the effectiveness and feasibility of the presented device are verified by the experiment..