Design And Implementation Of A Contactless Power Transfer System

In modern industry, power is mainly transferred through a wire or electrical connectors for power supply. When the power is supplied for moving objects, contact power supply will have the friction and wear, and in the field of high power, chemical, explosive and so on, contact power supply affect the safety and reliability. In the view of the above problems, to provide a new way of power supply is particularly important. Contactless power transfer technology is a new technology based on the principle of induction energy transfer to compensate these shortages.First, this paper investigates the research background and significance of the contactless power transfer technology, and analyzes the major technologies used in the system: contactless power transfer technology, soft switching technology and resonance technology. The realization of a soft switching in the full-bridge phase-shifted converter and the six different working processes in soft switching period are both discussed.With the above theory as a foundation, this paper designed a set of contactless power transfer system. And the input is mains supply, the output is dc voltage 24V, the maximum output current is 20A, the transmission efficiency is more than 80%, and it has over-flow and over-temperature protection function. The system mainly includes the power transfer and power receiving parts. It realizes the relative separation of the power supply and the electric equipment, and the equipment can relative move, so it overcome the shortage of the contact power transfer system. The contactless transformer transfers the power through the principle of electromagnetic induction. Because of using the contactless power transfer technology, the shortage of efficiency decline must be overcome. So the system uses the soft switching technology to reduce the switching loss in the control part, and resonance technology in the contactless part. It also has over-flow and over-temperature protection circuit to enhance the stability. This paper completes the input circuit, full-bridge soft switching circuit, phase-lifted control circuit, transformer, contactless transfer, output rectifier filter circuit, output voltage feedback circuit and so on.Finally, this paper completes the installation and the debugging, gives the experimental results and data, the methods and pictures of debugging, to confirm the feasibility and practicality.