Simulation On The Pitch Control Of Direct-drive Permanent Magnet Synchronous Generator

China is one of the countries that have abundant wind resources. The energetic development and utilization of wind energy has an important strategic significance on energy security, also has significance on environmental conservation and economic growth。With the advancing wind power generation technology,the unit capacity of wind turbine had increased from primary tens of kilowatts to MW. Meanwhile,the hypergrowth of computers and automatic control technology has made the control mode of simple fix pitch control to pitch control. Now,doubly-fed and direct drive is the most common big-size wind energy power generating units. Direct drive wind turbines have greater potential and used on the sea,for they have been taken of gearbox. As the research object to 2MW/Z72 direct-drive permanent magnet synchronous wind generator, this paper expands its research on modeling and simulation and its analytic research on control characteristics of the pitch controller. The main contents are as follows.(1)Modeling of the direct-drive permanent magnet synchronous wind generator. The mathematical models of subsystems of the direct-drive permanent magnet synchronous wind generator were modeled in the platform of Matlab/Simulink. Include model of rotor aerodynamic system,model of drive system,model of tower dynamics,model of electric conversion and model of pitch actuation system.(2)Establishment of the model of pitch control. The transfer function model of the pitch control system——the transfer function from pitch angle to the wind turbine rotational speed, was established based on the speed feedback control in the light of operating characteristic of the wind turbine. The transfer function reflects the effect of the changes of pitch angle on wind turbine rotational speed.(3)Simulation on the Pitch Control of Direct-drive Permanent Magnet Synchronous Generator. PID,Fuzzy-PID and LKal-Fuzzy-PID controller are designed for the pitch control system. The control performances are simulated and analyzed by Matlab. And also the results are compared. There into,PID control has overshoot of 9.78%,Fuzzy-PID has that of 8% and LKal-Fuzzy-PID has that of 2.44%. The results showed that, compared with the other two controllers,LKal-Fuzzy-PID has the advantages that it can eliminate the noisy signal commendably,has good control performance,has few control static error and good stability stable. It improves the control effect of the system. These showed that the control method of LKal-Fuzzy-PID has high theoretical and practical significance.