Study On Multi-Physical Field Analysis And Compensation Method Of Non-Contact Transformer

Wireless transmission technology is one kind of new power transmission mode,which has a very broad application prospect.As its core component,non-contact transformer has the advantages of no friction,no electric spark and relative movement.It is widely used in power systems,aerospace,biological medicine,steering drilling,and so on.The electrical characteristics and temperature characteristics of non-contact transformer are affected by the structure,material,circuit and operating environment,and they are directly related to the security and stability of the whole wireless transmission system.In this paper,the coupling model of the circuit field and the magnetic field of the non-contact transformer is set up,and the simulation calculation is carried out by using the finite element multi-physical field analysis software COMSOL.The transmission power and transmission efficiency of three kinds of materials under different cutting structures at different frequencies,such as permalloy,nanocrystalline,ferrite are analyzed.Secondly,the calculation method of self-inductance,mutual-inductance and coupling coefficient is derived,and the corresponding parameters of the transformer are obtained;the transmission capacity of the non-contact transformer in the four series compensation modes of S-S,S-P,P-S,P-P is analyzed,and the transmission capability in time and frequency domain is calculated.The simulation results show that the transmission capability of the series-parallel model is stronger.Thirdly,the coupling model of circuit field-magnetic field-heat transfer field with compensated non-contact transformer circuit is constructed.The temperature distribution of the non-contact transformer,the change of the temperature with time and frequency and the transmission performance of the transformer under the influence of temperature are simulated and analyzed.Then,the measures to reduce the temperature of non-contact transformer by increasing the convection heat transfer coefficient are also analyzed.Finally,the test platform of non-contact transformer is constructed and tested.The change of transmission capacity and temperature of ferrite and permalloy was compared,which lays a good foundation for further optimizing the test system of non-contact transformer.