The Research On Control Technology Of Hybrid-Excitation Synchronous Wind Power System

Nowadays, energy sources consume increasing daily and environment empoison being serious gradually, in the exploitation for the renewable energy source, wind power is paid great attention by more and more countries because of its standout excellence. The wind power generation technology also becomes research hotspot of scholars all over the world. The Hybrid-Excitation Synchronous wind power system will become one of the most competitive wind power generation for its high efficiency and practicability.Based on the traditional wind power generation, this paper emphasizes the key technology of high-capacity direct-driven wind generation. Taking the megawatt level Hybrid-Excitation Synchronous generation (HESG) wind power system as the major research object, a comprehensive research on its generator and converter control technology is done in this paper.Firstly, the current situation of the wind power industry and wind power generation technology, and the development dynamic of wind power generation are reviewed in this paper. Secondly, the overall structure of the HESG wind power system is present, with the function of every compound. By comparing with the other traditional wind power generation, the superiority of the HESG wind power system is obtained. The variable speed constant frequency principle of the HESG wind power system is analyzed. The converter structure according to its requirments is designed. The power control strategy is proposed, and the main function of generation host controller is given. Thirdly this paper discusses the characteristics of the HESG, and analyzes the basic structure and operating principle of HESG. Mathematic modle is established which includes the ordinally mathematic model in six-phase coordinate system and mathematic model in two-phase revolution coordinate system applying coordinate alternation. The optimizing PID algorithm is utilized to achieve excitation control goal, and simulation analysis on synchronous generator by MATLAB is done. Finally, because the converter in HESG wind power system is one of the focal points of this paper, the indirect current control principle and the direct current control principle with their advantage and disadvantage are discussed, and the dual inverter control scheme is proposed, with simulation study on both of the generator and the uncontrollerble rectifier system and the dual PWM inverter system.