Research on Cable High Frequency Passive Equivalent Circuit Model Based on Vector Fitting

The modeling method of the cable mainly has physical law and black box method, in order to avoid the impact of factors such as external environmental factors and internal skin effects in physical method, this paper is based on vector fitting algorithm, using black boxes method Modeling the cable. Only the relationship between the input and output of the cable is considered, and the high-frequency passive equivalent circuit model of the cable is studied. First, this paper takes the 10kV high voltage cable produced by a company as the experimental object, and the impedance of the cable is measured at a frequency range of 1 MHz-10 MHz; Secondly, the impedance amplitude spectrum and impedance phase spectrum of the cable at high frequency are fitted by using the vector fitting algorithm and the circuit synthesis theory, and the high frequency circuit model of the cable is obtained; Then, the pattern search algorithm is used to optimize the model passively, and then a stable high frequency passive circuit model is obtained. Finally, MATLAB/Simulink simulation is used to verify the correctness of the above model. This model has a certain guiding role for the study of high-frequency signals in cable and the construction of cable model under the condition of high-frequency.