Research On Bi-directional Inverter With High-frequency Link

Bi-directional inverter with high-frequency link has the advantages such asbi-directional power flow, high frequency electrical isolation, simple topology, few stagesof power conversion, and it is especially suitable for occasion in bi-directional power flow.A new-type bi-directional high-frequency link inverter's circuit configuration andtopology, shifting control strategy, analysis of steady principle are deeply investigated inthis thesis. By using single polarity phase shifting control, cycloconverter turns on/offwhen the voltage of the transformer is zero, then the cycloconverter can be zero voltageswitching(ZVS). A single polarity SPWM wave voltage is got before the output filter andthe output is good. The theoretical analysis is verified by the simulation results.The prototype for 1KVA 270VDC/115V400HzAC bi-directional high-frequency linkinverter is developed, and the test results are given. The result of principle test wasconsistent with the theoretical analysis and the simulation result, confirmed bi-directionalhigh-frequency link inverter feasibility.The work process and the principle of a UPS system that is based on bi-directionalhigh-frequency link inverter have been analyzed. Using bi-directional high-frequency linkinverter may make the main circuit of the UPS system to be more succinctly. Thesimulation result has confirmed the feasibility of the UPS system which is based onbi-directional high-frequency link inverter, and hi-directional high-frequency linkinverter's characteristic such as bi-directional power flow.Through deeply comparison and research on the control strategy, principlecharacteristic, design criteria for the key circuit parameters of single polarity and doublepolarities phase shifting controlled bi-directional inverter with high-frequency link, thisthesis has obtained the important research conclusion.