Non-grid-connected wind power system and its high power DC-DC converter

Wind power industry has become an important strategy to alleviate supply shortage of power. Compared with net-grid-connected wind power system, it is one of the effective ways to reduce construction cost and no-fluctuation to the grid by directly applying the large-scale wind power to high energy-consuming industries. So it is an effective and economical approach to increase the proportion of wind power in China´s energy structure, and we call this new system ldquonon- net-grid-connected wind power systemrdquo. This paper introduced the composition of the non-grid-connection wind power system, provided the structure program of wind power generation system with flywheel energy storage battery, then introduced the HVDC Light Transmission Technology adopted in this system, and pointed out the high input voltage was the main challenge of high power DC-DC converter. After reviewing the main solutions of input-voltage sharing of the high voltage DC-DC converters, a novel equal input-voltage sharing strategy of input-series output-parallel (ISOP) converter was presented. This strategy was designed to solve input-voltage unbalancing at light load. In the end, simulation results were presented to show the effectiveness of this control method.