A RESONANT CONVERTER FOR UNIVERSAL WIND APPLICATION

WITH A VARIABLE-SPEED GENERATION (VSG) SYSTEM, A WIND TURBINE CAN TURN AT ANY SPEED AND STILL PRODUCE CONSTANT FREQUENCY AND VOLTAGE POWER WHICH IS COMPATIBLE WITH THE GRID. THE PRIMARY BENEFITS OF VSG INCLUDE INCREASED ENERGY PRODUCTION, INCREASED POWER CAPACITY, SOFT-STARTS, CONTROL OF TORQUE PERTURBATIONS, DYNAMIC ELECTRICAL BRAKING, AND POWER FACTOR CONTROL. ALL OF THE MODERN TECHNIQUES FOR IMPLEMENTING VSG RELY ON A POWER ELECTRONIC CONVERTER OF CONDITIONER. CONVENTIONAL CONVERTERS HAVE SEVERAL WELL-KNOWN PROBLEMS: HIGH COST, EXCESSIVE POWER LOSSES, HARMONICS LOSSES AND WINDING DAMAGE IN THE GENERATOR, POOR POWER FACTOR, AND AUDIBLE NOISE. AN INNOVATIVE RESONANT CONVERTER KNOWN AS THE UNIPOLAR SERIES RESONANT CONVERTER (USRC) WOULD MAKE DRAMATIC IMPROVEMENTS IN EACH PROBLEM AREA. THE USRC USES THYRISTORS WITH ZERO VOLTAGE AND CURRENT SWITCHING, THUS MINIMIZING LOSSES AND COST. IT IS ALSO INHERENTLY BI-DIRECTIONAL AND PRODUCES SINUSOIDAL VOLTAGE WITHIN IEEE 519 STANDARDS AT BOTH THE INPUT AND OUTPUT, THUS ELIMINATING SUPPLEMENTAL FILTERS, AUDIBLE NOISE, AND WINDING DETERIORATION. IN PHASE I, A 400 KW USRC THAT CAN BE USED WIDELY IN MANY TYPES OF VARIABLE-SPEED WIND TURBINES WILL BE DESIGNED AND ASSESSED AS TO FEASIBILITY (PERFORMANCE AND COST). IN PHASE II, THE DESIGN WILL BE ASSEMBLED AND INSTALLED IN THE FIELD IN AN ADVANCED WIND TURBINE.