Research On Non-grid Small Wind Power Generation System Based On Asynchronous

Wind power industry is in the ascendant all over the world, international research focus is mainly large-scale grid wind power system now. Relatively, the small wind power generator system is more suitable for distributed generation.The research of small wind power generator system which knows for its higher reliability and lower cost has great significance which has not only enhanced the market competitiveness of it but also accelerate the popularization and application of the small wind power generating system.Cage induction motor structure is simple, durable, low-cost, small-size, easy to maintain, and can be de-excitation protection in short circuit fault.Because of these advantages, it is easy for wind power systems to meet the high reliability, maintenance-free performance of small wind power generating system. However, literatures especially on the design of an asynchronous generator can hardly be found at home and abroad, and its design is generally in accordance with motor programming. Wind induction generators designed according to the asynchronous motor programming can't work well. Its efficiency is very low when in low-speed state, too.The topic has done targeted research on non-grid small wind induction generator system. In order to rise the efficiency of energy conversion, the mathematical model of induction generator considered the iron-loss has been made, and based on this model, the simulation of the non-grid small wind generator system has been completed; According to the research and summarizes on results of optimal efficiency control in induction motor, based on the largest wind energy tracking control, a method of the optimal efficiency control for wind induction generator is proposed and a special method to design low-voltage low-power direct-drive cage asynchronous wind power generation machine is put forward.Lots of in-depth experiments were done on the control platform which based on Freescale's 56F8037DSP. There is a detail introduce of the whole control system including the software and hardware design in this thesis. The final experimental results show that the proposed regulation of optimal efficiency control based on slip frequency can significantly improve the output of the system, especially improve the efficiency in low-speed state.