The Research On The Modeling Method Of High Frequency Passive Circuit Model For The Potential Transformer

Power system electromagnetic transient simulation, as well as electromagnetic compatibility analysis of the need to build electromagnetic transient calculation model of the potential transformer. A high frequency circuit model is setup based on black-box technique in this paper. The Y parameters is transformed from the S parameters of PT and approximated by rational functions using the Vector Fitting at first. In order to improve the simulation stability of circuit model, a optimization to the rational function of admittance matrix of PT and circuit components of the equivalent circuit are calculated , which enforces the circuit model is microcosmic passive. At last, two kinds of circuit model composed of R, L, C, G and real transformer are synthesized. The simulation and measurement results are presented, confirming the validity of the proposed model. The proposed method is effective and general which provides a powerful tool for researching the interference caused by VFTO to the secondary circuits and provides a new way for modeling the high-frequency passive model of the transforming device.