Research On New Rotary Non-contact Power Transmission System

Rotary non-contact power transmission technology is based on the law of electromagnetic coupling coupling,use of power electronic converters and rotary transformers to achieve electrical energy from the static end to the rotating end of the non-contact transmission,instead of the traditional power supply in the wire,brush and slip ring.The existence of improved power supply reliability and security.In this paper,a new type of rotating non-contact power transmission system is designed.The present situation of rotating non-contact power transmission technology is briefly introduced.The structure and basic principle of the rotating non-contact power transmission system are analyzed.The equivalent circuit and magnetic circuit model of the rotary transformer of the core are analyzed.Due to the large air gap between the primary windings of the rotary transformer,the coupling coefficient of the transformer is low.This paper presents an improved transformer structure that improves the coupling coefficient of the transformer by increasing the utilization ratio of the core space without changing the physical size of the original transformer model.The three-dimensional model of the original tank transformer was established and simulated by using Ansoft Maxwell software.The modified transformer structure with the best transmission efficiency was determined.Obtained the relationship of coupling coefficient k and the mutual inductance M with the size of the air gap.The magnetic field distribution and the magnetic flux density distribution of the two kinds of transformer structures are analyzed and compared by using the simulation of the two-dimensional model,and the superiority of the improved transformer model is verified.The circuit characteristics of the system are simulated by Saber simulation software,and the relationship between the phase shift angle and the primary voltage,current and output voltage of the transformer is obtained.The experiment platform of rotary non-contact electric energy transmission system is built and the relevant experimental verification is completed.The experimental results show that the improved transformer model can improve the coupling coefficient k when the air gap exceeds 3mm,and the maximum increase is 35%.