Study On High Frequency Link

Based on an overview of high frequency link (HFL) inverters, the advantages and disadvantages of HFL inverters in some important voltage mode and current mode are discussed in the dissertation. The current mode HFL inverters solve the inherent voltage surge problem in voltage mode HFL inverters, so they have better performance and application prospect in low power application. But the voltage mode HFL inverters often have performance and application in high power application.The phase-shifted controlled voltage mode converters with HFL are deeply investigated. This kind of converters is constituted of inverter, high frequency transformer and output cycloconverter. The mode is suit for high output voltage field. The SPWM wave is filtered into steady commercial frequency sinusoidal voltage with low harmonic by output cycloconverter.From the viewpoint of the whole topologies of HFL inverters, a new scheme of HFL inverters is applied. Based on phase-shifted controlled voltage mode, ZVS is achieved with the output capacitance, output inductance of MOS and leaked inductance of transformer.The inverter is a small independent system. Therefore, to achieve a good performance both statically and dynamically, closed loop control method has to be applied. The paper takes advantage of a single close-loop control method based on voltage feedback, and enables the inverter to produce steady sine wave by the digital PID adjuster designed.The high frequency transformer is investigated and compared with power transformer. The high frequency transformer suited HFL inverters is designed and parameters are achieved in this paper.The whole simulation module of control system is built up under the powerful MATLAB/SIMULINK platform. It can precisely reflect the system properties. It will become easier that we select appropriate parameters. Therefore the simulation module would shorten the cycle and economize the cost.