| This article briefly addresses the state of art of domestic and foreign small-scale grid-connected wind power generation, and discusses the problems of the existing typical wind power converter topology used for small-scale grid-tied WEGS. It presents an efficient, practical, low-cost small-scale wind generation based on high inductance permanent magnet generator topology and proposes a simple control scheme of the CSI in small-scale wind power technology.The system uses a switched-mode rectifier in conjunction with a high- inductance generator that allows generator torque and power to be controlled via the switch duty-cycle. The system maximizes output power for wind speeds below rated, and limits turbine speed for higher wind speeds, with simplified circuit topology, which possess feasibility in practice. However because of the fluctuation of the output direct current of high inductance PM, the harmonics of output grid-connecter current is large with common SPWM control method. In this respect, through deeply analysis of the transient process of CSI circuit, according to power balance principle between DC-side and grid side, which derives the average voltage expression of inverter input DC-side in half-cycle , the paper presents a new control strategy of CSI. The relation between modulation index (m) and the grid-current amplitude, the instantaneous current of DC side can be derived. The paper constructs the small-scale wind generation and its control strategy used with matlab/simulink. The simulation results proved: the topology is simple and the proposed control method overcomes the bad effect of the fluctuation of direct current, and dynamic performance of the new control strategy is good, that is grid-connected current follows the changed direct current quickly. By comparison between the proposed system with small-scale wind generation, the conclusion that in any wind speed, the transform efficiency of the later is higher.
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