Novel Hybrid Analytical/Numerical Conducted EMI Model of a Flyback Converter

A hybrid analytical/numerical conducted an electromagnetic interference (EMI) modeling approach, which adopts both numerical method and analytical method, is proposed in this paper. In this model, the noise source is calculated directly with the original data from oscilloscopes. The noise path at different operating status is extracted from the original converter topology and its analytical expression is then derived. Also, according to the EMI receiver detector mode, the algorithm of the EMI receiver is proposed in this paper. Peak (PK), average (AV), and quasipeak (QP) values of the EMI can then be calculated to analyze the impact of each relevant component. The analytical method is provided to carry out PK, AV, and QP simulations accurately and fast. The simulation and experimental results for common mode leakage currents validate this EMI model. Furthermore, two analysis examples are given to illustrate how this model is applied for engineers.