Analysis of Parasitic Parameters and Winding Loss Characteristics of High-Frequency Transformer under Different Winding Structures

Abstract

Abstract With the development of the smart grid and the increasing access of renewable energy to the distribution grid, the traditional AC power grid puts forward an urgent demand for power electronic transformer (PET). The high-frequency transformer (HFT) serves as the core equipment of PET, and its electromagnetic structure and parasitic parameters are the hot spot of study in the field of power electronics. In this paper, the parasitic parameters, winding loss, and leakage magnetic field characteristics of the 20 kHz, 20 kVA HFT are investigated under different winding structures. The results show that the higher the degree of crossover of HFT winding, the lower the leakage magnetic field. The cross winding reduces winding loss and leakage inductance, and also attenuates the impact of frequency variations. The higher the winding height, the lower the leakage inductance. As the insulation thickness increases, the leakage inductance rises. The distribution capacitance varies opposite to the leakage inductance. Based on the analysis of winding loss and parasitic parameters, as well as the consideration of insulation, the final winding layout, the height of winding and the thickness of insulation of the HFT are determined.