The generalized MFAC control algorithm is proposed for the disadvantage of the basic MFAC controller in the strong nonlinear system with large time delays.As the same time,the algorithm is applied in the double flume liquid temperature control system,the simulation of the control system is carried out.The simulation results presents the the control structure and control algorithm track ability, anti-interference,rubustness and load adaptability meet the demand of control design.The designed system have good control qualities.

The characteristics of PID controller, Active Disturbance Rejection Controller (ADRC) and Linear Active Disturbance Rejection Controller (LADRC) are introduced in the paper, then the parts which can be improved are analyzed, which leads to the topic of balancing linear and nonlinear elements in controller. LADRC with FFTD is used as an example in simulation experiment operated in Matlab7.0.The results shows that the control effect of LADRC with FFTD is better than other three controllers above. The simulation results and perspectives in paper offers reference for combining linear and nonlinear controller and balancing difficulty and performance.

For implementing excellent control to nonlinear systems with long time-delay, a new intelligent control algorithm of cloud models was proposed. This algorithm presents the uncertainty reasoning of control rules based on cloud model. This model is a new method for transformation between qualitative and quantitative in the knowledge. The intelligent controller uses the theory of the fuzzy control, designing a variant dimension cloud model intelligent controller containing a one-dimension cloud model controller to eliminate steady-state error, which is used for thermal power plant boiler superheated steam temperature. It also shows that the cloud controller is simple and easy, directly perceived through the senses, and has strong robustness, better control performance, and good application.

This paper analyzes the operating characteristics of wind turbine and introduces the principle of maximum power point tracking control system of variable speed wind turbine. A improved maximum power tracking control strategy is proposed for large inertia wind power systems in order to achieve maximum wind power capture and increased utilization of wind energy when wind turbines is below the rated wind speed. A variable speed wind power generation system is modeled and simulated in the Simulink environment of the Matlab .The simulation results proves the correctness and feasibility of the tracking control strategy suggested in this paper.

With the unit capacity of the wind turbine is increasing, analyzing, suppressing of gird harmonic and reducing the grid harmonic pollution by the wind turbine have become one of the issues of common concern. For the characteristic of the grid voltage harmonic components which is the interference source with the fixed period, the repetitive control theory was adopted to design the gird-side converter, and the traditional control strategy of the voltage current double closed-loop was compared with the repetitive control. Harmonic suppression characteristics were studied in the paper. Finally, Matlab-Simulink simulation software established a repetitive controller simulation model of the gird-side converter controller, simulation results showed the correctness and feasibility of suppression for the periodic harmonic by the repetitive control strategy.