Method for estimating electromagnetic interference of power electronic conversion system based on power transmission line

Abstract

The invention relates to a method for estimating electromagnetic interference of a power electronic conversion system based on a power transmission line. The method comprises the steps of enabling thepower transmission line between a power electronic conversion device and a power system to be equivalent to a transmission circuit; establishing a physical structure of wideband equivalent resistance-inductance steplike topology of the power transmission line; accurately identifying and optimizing wideband key parasitic parameters of the resistance-inductance steplike topology of the transmissionline based on a vector fitting iteration strategy; and substituting the calculated key parasitic parameter values of the resistance-inductance steplike topology into the transmission circuit and estimating a difference mode/common mode conducted electromagnetic interference level of the power electronic conversion system. According to the method, the numerical equivalence is performed on the basis of a resistance-inductance steplike topology theory, so that the frequency change transmission characteristic of inherent parameters of a cable is represented, accurate approximation and stable convergence of a prediction model are achieved, and an effective theoretical basis is provided for achieving accurate identification of wideband parasitic parameters of the model and EMC design of the power electronic conversion system.

Description

technical field [0001] The invention belongs to the technical field of power transmission, in particular to a method for estimating electromagnetic interference of a power electronic commutation system considering power transmission lines. Background technique [0002] The power electronic commutation system constructed by the insulated gate bipolar transistor (IGBT) has a compact structure design and a complex electromagnetic working environment, and produces a high instantaneous current change rate in the high-frequency switching state di / dt and voltage change rate dv / dt, it is difficult to study the electromagnetic interference (electromagneticinterference, EMI). Due to the existence of high-frequency parasitic parameters in the circuit, the high-frequency behavior of components is quite different from the expected ideal characteristics. It is necessary to obtain the corresponding high-frequency model through circuit synthesis theory. For conduction coupling interference...

AI Technical Summary

Problems solved by technology

The traditional vector fitting method proposed by Gustavsen B and Semlyen A et al. can achieve fast parameter estimation, but the higher order of the transfer function also complicates the realization of the circuit, resulting in the least squares fitting residual problem that deteriorates the convergence

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