Wide Frequency Modeling for the Valve System of HVDC Converter Stations Based on Brune Synthesis Method

In order to calculate and predict the EMI noise produced by the valve ignition, it is essential to develop accurate models of valve equipments (thyristor, snubber circuit, equalized capacitance, saturation reactor) over a broad frequency range. The wide frequency modeling for the valve system of HVDC converter station based on Brune synthesis method was proposed in this paper: After measuring the frequency dependent impedance of the elements, the wide frequency equivalent circuit model of valve elements can be set up with rational approximation and Brune synthesis method. At last the equivalent circuit model is put into EMTP to simulate, and compared with the measuring results to ensure the efficiency and accuracy of the model