The switching device in a power converter can produce very serious electromagnetic interference (EMI). In order to solve this problem and the associated reliability and stability issues, this article aimed to analyze and model the boost power factor correction (PFC) converter according to the EMI conduction path. The sources of common-mode (CM) and differential-mode (DM) noise of the boost PFC converter were analyzed, and the DM and CM equivalent circuits were deduced. Furthermore, high-frequency modeling of the common-mode inductor was developed using a precise model, and the EMI filter was designed. According to the Class B standard for EMI testing, it is better to restrain the EMI noise in the frequency range (150 kHz to 30 MHz) of the EMI conducted disturbance test. Using this method, a 2.4-kW PFC motor driving supply was designed, and the experimental results validate the analysis.

The existence of high-frequency components in common-mode (CM) current would reduce the stability of a non-isolated PV grid-connected system. It has great impacts on the output power quality when the generated power from PV is low. The method of single CM inner loop in suppressing the high-frequency components has poor effect. Based on the CM equivalent circuit model and the cause analysis of the CM current, a novel dual CM inner loops method is proposed to restrain the high-frequency components in CM current. This method not only meets the grid connection demand of CM current, but also overcomes the high frequency resonant problem. Furthermore, the high-frequency components in CM current from the outer parasitic circuit are substantially reduced. Finally, the proposed method is verified by simulation and experimental results.

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Leakage inductance is one of the key parameters of a transformer, and it is often intentionally integrated into transformers. Rogowski’s equation is generally used for leakage inductance calculation; however, it is only applicable to concentric winding transformers where windings have the same height. Consequently, it has limited applications. This paper proposes a transformer leakage inductance calculation method using a double Fourier series. The limitation of Rogowski’s leakage inductance equation was analyzed in practical applications, and a new model for calculating the leakage inductance of a double-group-overlapping winding transformer was derived. Experimental prototypes of transformers were developed, and their simulation models were built in Ansys. The correctness of the proposed calculation method for transformer leakage inductance using a double Fourier series was verified by comparing the calculation results with the simulation and measured ones. A sensitivity analysis was also conducted by studying the variations in different parameters that might affect the leakage inductance value. The proposed calculation model gives an intuitive and simple method with less calculation and design effort while maintaining reasonable accuracy for leakage inductance calculation. In addition, the featured double Fourier series approach has a wider range of applications than Rogowski’s equation.