An Optimized Strategy for PWM Current Source Converter Based Wind Conversion Systems With Reduced Cost and Improved Efficiency

Recently, a series-connected current source converter (CSC) based configuration is proposed for offshore wind conversion systems. However, two problems exist in conventional strategy of such a system. One is increased cost on onshore CSCs, and the other is decreased operation efficiency of onshore CSCs. To solve these issues, this paper proposes an optimized strategy. First, the nominal number of onshore CSCs is optimized that a lower cost and a higher efficiency are achieved. Second, an optimal control scheme is proposed for onshore CSCs with lower operation loss. In addition, it is implemented without any extra components or auxiliary circuits. In summary, the proposed scheme gives a reduced cost and an improved efficiency of the offshore system with all the control objective being ensured simultaneously. Simulation and experiments are finally provided.