Study And Improvement Of Transmission Characteristics Of Contactless Power Supply For Railed Transportation System

Contactless power supply is a new technology of mobile power supply,based on the principle ofelectromagnetic induction. It has been widely used in logistics equipment because of its safety,flexible and clean. This paper studies the transmission characteristics of contactless power supplysystem for railed conveying equipment by theoretical analysis, simulation and experiment, thenimprovement measures are put forward.In the suspect of circuit characteristic, the circuit model of LCL resonant system isestablished,the ideal system power, efficiency and the secondary output transmission performance isstudied, and the resonance condition, impedance and output characteristics areanalysised.Howerver,some key factors such as system operating frequency, equivalent load, mutualinductance etc. are discussed in the paper,which provides the theoretical basis and foundation forsystem design and improvement.In the study of energy characteristics, the conduction, switching and coupling losses are studiedby qualitative and quantitative method. Various loss mechanism, amount of loss and improvementmeasures are discussed, and the loss of U type system is analysised by simulation andcalculation,including loss rate, loss variation and output waveform.To improve the system performance, focusing on the primary converter and electromagneticstructure,power factor correction, inverter control and soft switch technology are discussed, as well asmutual inductance and structure improvement of U type syetem, then,the characteristics of magneticfield, voltage and coupling of various electromagnetic structure are analysised and compared.On the basis of the theory and simulation,in oder to further improve the reliability, the thermaldesign, electromagnetic compatibility and protection circuit is discussed in this paper,which gives thecorresponding circuit design. Finally, on the application platform of rail-guided vehicle, theimprovement effects are verified by experiment, which compared the inverter output and systemoutput, and shows that the power factor and transmission performance is improved obviously.