Pitch Control Servo System In Mega-watt Class Wind Turbine

Beginning of the 20th century, with the rapid development of industrial technology, the energy demand is rising. In order to get the rapid economic development, even at the expense of the environment. In the pollution is worsening, energy shortage today, global new energy boom under way, wind power technology gets more attention. Our wind power technology started later than others, the rapid development in recent years, the total installed capacity and in terms of new capacity has been in Asia, the world second. But our country has independently developed small wind turbine wind turbine mainly. In large wind turbine technology, there is still a gap with others. Therefore, large-scale wind turbine technology research has great significance.In this paper, the variable-pitch control theoretical basis was put forward by research on wind turbine aerodynamic characteristics, and established mathematical model of wind turbine .Then the pitch control system by electromotor was researched; the mathematic model operation principle of PMSM and the theory of vector control for PMSM are illuminated .Found wind turbine has strong nonlinear, multivariable, and other characteristics , if control with the PID, is highly difficult to achieve good performance; and the randomness of wind, like wind speed, direction, size, change over time, which is difficult to establish accurate mathematical model of control object, it also makes the difficult to get a good result. Therefore, the study megawatt wind turbine pitch control technology to improve the adaptability of variable pitch wind turbine power regulation on high-frequency wind speed , become an important issue before us.For the above-mentioned technical problems of large-scale wind turbine,this paper combining Fuzzy control technology with traditional PID is proposed in this paper, combined the advantages of Fuzzy control doesn't depend on precise mathematical model of control object and strong robustness with simple structure and easy adjustment advantages of traditional PID. In the last of this paper I used discrete look-up table to design a Fuzzy-PID controller of variable-pitch control system. The MATLAB simulation results show that the controller has improved robustness and response speed of traditional PID controller and achieved a good control effect.