Study on Characteristics of no-load Converter Transformer closing Accessing to High-Cable Rate Network

Abstract

When the converter transformer is closed at no load state, the transient voltage is too large, which may cause the transformer core to saturate; meanwhile, the capacitance of the cable line to the ground is much larger than that of the overhead line, which may cause ferromagnetic resonance phenomenon. Taking the parameters of typical transmission line and 500kV converter transformer as an example, the simulation results of Matlab are used to analyze the possible effects of no-load closing of converter transformer under different cable-forming rates and different outlet modes, and put forward targeted measures, which have certain reference value for the future design of the converter station outline.