Research On Maximal Wind Energy Tracing And Excitation Control Of Wind Power Generation System Using Synchronous Generator

With the deepening energy crisis and the increasingly serious ecological damageto the environment,wind energy (reproducible energy), which is one of the mostimportant substitute energy in the21st century,is of great significance for abating theshortage of resource. So the development of the wind energy, has become a hot topicin the world. Under the random wind speed, it is the objective how to extractmaximally the wind energy and improve the reliability of the wind power generationsystem during the dissertation. The detailed research works include(1)This paper summarized and analyzed the present wind power generationsystem and a novel method via cloud model optimal gradient is proposed to trace themaximal wind energy of wind power generation system and maximum power pointtracking of wind power generation system based on fuzzy inference optimal gradient,meanwhile compared the fuzzy control of traditional three-point method with them inthe same system conditions. At last, simulation results show the methods proposed iseffective.(2)A variable-step maximum power point tracking (MPPT) algorithm(optimalgradient method) for wind power generation system is proposed．At present,theexisting MPPT algorithms were wind speed tracking control strategy and speedfeedback control strategy, and sometimes an anemometer is needed to measure windspeed which will bring more cost and complex structure．This paper proposed avariable-step optimal gradient algorithm to track maximum power point for windpower generation system, its advantages are that no measurement of the wind speed isrequired, and can improve the power generation system of wind energy utilization.(3)The model of wind power generation system and wind turbine were built andsimulated in MATLAB． The fuzzy reasoning and cloud model reasoning aredeveloped,and the MPPT algorithm proposed in this paper was simulated anddiscussed in details,the results of simulation were used to prove its feasibility．Thispaper has simulated the controller with MATLAB.From the point of tracking performance and anti-disturbance, the optimal gradient method is better thantraditional algorithm, which can depress the oscillation more efficiently and has arapid rising response, arrive at stabilization more rapidly．(4)The excitation model of synchronous generator(machine infinite-bus systemstate equation) was built,cloud model inferer are developed and stable voltage outputcontrol of excitation synchronous generator based on cloud model theory, the inferer isdivided into two parts,for expel the voltage reasoning of blast and the velocityreasoning, which input respectively for their deviation and deviation rate,and outputsignal for the respective reasoning. Meanwhile, optimization of those parameters forreasoning, thus the correctness of the proposed method is verified by simulation.