The Study Of Design Optimization For Brushless Doubly-fed Wind Power Generator

The Brushless Doubly-Fed Generator (BDFG) abolishes the brush and slip ringand has many advantages such as reliable operation, small frequency converter capacity,low system cost and flexible adjustment of speed and power factor. So there is a broadapplication prospect of BDFG in the field of wind power generation. However, atpresent it is lack of the research about BDFG design optimization. Based on the Projectof State Key Laboratory of Power Transmission Equipment&System Security and NewTechnology of Chongqing University, the thesis focuses on the research of the BDFGwith cage rotor from the aspects of electromagnetic design and optimization algorithm.Firstly, the basic structure and the operating principle of BDFG and its powergeneration system were briefly introduced. The voltage equations and the equivalentcircuit were deduced in detail. On this basis, the study of the power flow andperformance calculation method was researched. The BDFG electromagnetic designformulae were then obtained. And the corresponding electromagnetic design softwarewas developed by the platform of Visual Basic.Secondly, the influences of the wind turbine characteristic to BDFG were analyzed.Then the design principles and design objectives of BDFG were put forward. Accordingto BDFG electromagnetic design software, the preliminary electromagnetic designscheme was obtained and discussed.Thirdly, the standard Particle Swarm Optimization (PSO) algorithm and researchstatus of PSO improvement strategy were introduced. Furthermore, the Oscillating AllParameters Strategy Particle Swarm Optimization (OAPS-PSO) algorithm was putforward and validated by4classic Benchmark functions.Finally, combining with the characteristics of wind power generation system, theBDFG design optimization model was established. The OAPS-PSO algorithm was usedto optimize the design of BDFG. And then the optimization results were obtained andanalyzed.The results show that the derived performance calculation method andelectromagnetic design formulae of BDFG are correct and effective. The OAPS-PSOalgorithm can effectively overcome the premature convergence, has better globalconvergence ability and is suitable for solving the multivariable and complicatedoptimization problems. The obtained optimization schemes of BDFG reduce the cost or increase the efficiency, which suggests that the optimization object has been achieved.The study of this thesis provides the theoretical foundation for the electromagneticand optimization design of BDFG, and the optimization schemes of BDFG are valuablefor the manufacture of BDFG prototype.