Design And Control For High Inductance Generator Based On Small Scale Grid-connected Wind Power Generation System

With the rapid development of wind power generation in the global market , small-scale wind power generation market share is growing by about 35% annually. Batteries are usually adopted in the current small off-grid wind power generation which results in high costs and maintenance costs. And therefore the wide promotion and application of such systems face a serious of challenges especially in the vast area covered by the grid. Meanwhile low-cost, energy-efficient small-scale grid-connected wind power systems have been paid more and more attention and demanded increasingly.The topology of a new wind power system based on permanent magnet synchronous generator (PMSG)with high stator inductance and current source converter is simple. Bulky DC inductance and low reliability DC capacitor of the voltage inverter are eliminated by integrating the DC inductance into the generator. Fractional-slot concentrated windings and changing slot sharp are adopted to implement PMSG with high stator inductance in term of requirements of the system. The design theory of generator, main parameters, and cogging torque based on the above method are analyzed. Taking 10kW wind power system for example, the proposed design method and software of RMxprt are used to design generator, and then field-circuit method based on finite element method are adopted to calculate the generator characteristics under different loads and its inductance. The results show that the cogging torque is small with the sine wave of Back EMF and the inductance of the generator meets the system requirements. Besides, Grid-connected current waveform quality, system efficiency, generator efficiency and maximum wind power capture at different wind speeds are analyzed in details and validated by modeling and simulating the new small-scale wind power grid-connected system based on current source converter and the proposed PMSG by matlab/simulink.