Design And Simulation Of Medium-High Frequency Transformer

Medium-high frequency transformers(MHFT)play an important role in the fields which require limited space and weight of the equipment,such as offshore wind farms,rail traffic tractions and so on.Compared to traditional power frequency transformers,MHFT has smaller size,lighter weight and higher power density.MHFT is in line with energy-saving and miniaturization trend of the times and has good prospects for applications.Compared with traditional power frequency transformers,MHFT increases the working frequency,thus reduces the size and weight.When designing MHFT,engineers need to select lower-loss magnetic core materials and proper structures of windings so as not only to reduce the AC resistances,but also to pay more attention to insulation and temperature rise problems caused by smaller size.This paper focuses on the design and simulation of electromagnetic and thermal field of large-capacity MHFT.In the process of developing the large-capacity MHFT,the simulation tools can help engineers save time of manufacturing prototypes,cut the cost and shorten the research and develop cycle.Therefore,to find an accurate simulation method is of practical significance in engineering design.Finite element software,namely Maxwell,is used to simulate the electromagnetic and thermal fields of MHFT in this paper.It contains the calculations of the leakage inductance,AC resistance of common structure windings at different frequencies,the electromagnetic losses,stray losses and temperature rise on different cooling conditions.The rationality of the theory and simulation method is validated by the test of the prototype.