Wind Turbine Based On SMC Research Of Variable Pitch Servo Control System

In recent years, the traditional energy brings serious environmental problems to mankind and looking for new alternative energy has become a problem to be solved in the human sustainable development. Wind of the advantages of renewable, no pollution, has drawn great attention of the countries all over the world. Now, the pursuit of bigness and high performance of wind turbines has become a new trend in wind power market.Variable pitch control technology,as the key technology of large wind power system, researching on it has a very important practical significance.Variable pitch servo system is a complex, changeable, nonlinear and time-varying servo system. The traditional control strategy is difficult to achieve high precision control, it is necessary to adopt the advanced control strategies to ensure that the quality of the wind turbine high power output and the safe and stable operation. Based on the domestic 1.5 MW large doubly-fed wind power generator as the background, by applying the theory of sliding mode control(SMC) is applied to the variable pitch servo control combined with other control method, the paper in-depth research and analysis of the large wind turbines variable pitch control technology.First of all, this paper analyses the general structure of the large doubly-fed wind power generator set and introduces the main part of the mechanical structure and the system composition. The control system are introduced in detail. Variable pitch actuator has been selected and determined the PMSM electric drive mode. then emphatically analyzes the variable pitch control process. Important parameters of the control theory is introduced and derived, which provide a theoretical basis for the further research of variable pitch servo system.Then, the basic concept of servo system are introduced, the wind turbine variable pitch actuator servo system has been planed and designed overall, and the independent PMSM electric variable pitch control schemehas been determined. Finally, the simplified dynamic mathematical model was established in each parts of the wind power system, which laid a foundation for the next chapter controller design.Then, in view of the problem that traditional PID control can’t satisfy the requirement of the high performance, combining the theory of fuzzy control and sliding mode control theory, this paper designed a fuzzy PID and fuzzy sliding mode variable pitch wind power controller, which get a ideal control effect. Through the pitch Angle and the comparison of the output reactive power curve by MATLAB shows that the fuzzy sliding mode control not only weaken the chattering of the system, but also the control effect is better than fuzzy PID,which proved the feasibility of this scheme.Finally, researching the part in detail that electric servo actuator part is simplified in this previous two chapters. Combining sliding mode control,fractional theory, and the RBF neural networks technology, the paper designed a RBF fractional order sliding mode controller in the three closed loop position servo motor servo system. Compared with the traditional PID strategy, proved its superiority. And bringing this module to the whole power of the wind turbine simulation, the effect is compared with common sliding mode control.The simulation results show that the design of the fractional order sliding mode control strategy based on RBF without damaging its dynamic quality weaken the chattering effectively, more superior performance, not only ensures the stability of the unit output power,but also the effect is more realistic and accurate than the previous two methods, which is helpful for the application of practical engineering.