Research On Design Method Of Contactless Bus Converter

With the rapid development of science and technology,the application of electronic products is more and more extensive,and there are more and more power supply schemes under different application scenarios.In the autonomous navigation equipment such as aerospace and deep sea,due to its long internal transverse length and narrow circular section,the traditional centralized power supply design has some disadvantages,such as long production cycle and unfavorable maintenance.The modular design method based on function combination can improve production efficiency and facilitate rapid maintenance and replacement of components effectively.However,in order to power each functional module unit,it is necessary to study a contactless power supply scheme to replace the traditional centralized power supply.This paper presents a design method of Contactless Intermediate Bus Converter(IBC).The IBC consists of two same size coaxial coils on each side of the primary and secondary sides.In detail,the primary side is connected parallelly,and the secondary side coil is connected seriesly with center tap.The equivalent circuit model of contactless IBC is established based on the principle of electromagnetic coupling.The number of turns of primary and secondary coils are discussed,in order to obtain the positive and negative balance induced voltage.In order to improve the efficiency of the system in low-voltage and high-current,this paper studies the self-synchronous rectifier technology.The driving coil circuit model is established and the influence of driving coil layout on driving voltage waveform is studied.Based on the comprehensive comparison of the driving voltage oscillation peak,waveform stability and process realization,the optimal driving coil layout scheme is proposed.In order to understand the influence of core layout on duty cycle loss,this paper studies the relationship between magnetic core and system characteristics through finite element simulation software Maxwell,and establishes the mathematical relationship among system output voltage,coupling coefficient and load current,which contributes to optimize the number of magnetic cores.Finally,an experimental platform of contactless intermediate busconverter system with an output power of 120 W,output voltage of 20 V,maximum output current of 6A and overall efficiency of over94% is built.The coil optimization,drive coil layout optimization and magnetic core optimization is verified.