Song Lepeng

Simulation for strategy of maximal wind energy capture of doubly fed induction generators

In order to most effectively utilize the wind energy and improve the efficiency of wind generation system, an optimum control strategy of doublyfed induction generators (DFIG) was proposed, which made the system operation for both the maximum wind enemy captured below the rated wind speed. Based on the wind turbine characteristics and basic electromagnetic relationship of DFIG the mathematical models of the stator active power and reactive power of DFIG were derived to fulfill maximal wind energy capture and conversion. A dual-passage excitation fuzzy control strategy based on dynamic synchronous reference frame was applied to control the proposed optimal stator active and reactive power. The operational performances of the wind turbine system with DFIG with wind speed variation were analyzed and compared by using Matlab/Simulink . The results show the correctness and feasibility of the proposed control strategy.

Fuzzy controller in the largest double-fed wind power generator in the study of capture system

For the variable pitch grid-connected wind turbine maximum power tracking and improved power quality problems, using new double-fed machine constitutes a wind turbine, based on vector control and the whole fuzzy controller is used to achieve brushless doubly-fed variable speed constant frequency motor control. Self correct factor of fuzzy was introduced in the fuzzy controller design process. The fuzzy controller with parameters self-adjusting is changed different control requirements. Made below rated wind speed, according to wind speed changes, control of motor speed is used to obtain the best tip-speed ratio to achieve maximum power tracking and variable-speed constant frequency. Simulation results show that compared with conventional PID controller can more effectively reduce the vibration. Rapidly to achieve steady state, wind energy conversion system efficiency and quality is increased.

A Design of the Obstacle Avoidance Software for Solar Autonomic Trolley

A four-wheeled autonomic trolley of obstacle avoidance is controlled by way of front-wheel steering and back- wheel driving. Three pairs of ultrasonic sensors are, respectively, installed on the left front, front and right front of the trolley in order to measure the distances between obstacles and the trolley. Its control strategy is drived from the concept of path planning for mobile robot based on fuzzy logic. The reference variables are the current location coordinates, X Y, and tp(the steering angle to target point), thus to find out the output steering angle (hp) of the front wheel.

Simulation study of water level control system based on active disturbance rejection controller

PID controller can not perform well in liquid level control system because liquid system has characteristics of time-delay and inertia. Based on the characteristics of two-tank liquid control system, an ADRC is designed by using control technique of active disturbance rejection. In order to study the control performance of ADRC, the comparative analysis with PID controller is to be carried out in the research. Simulation research shows that water level control system based on ADRC possesses better rapidity, less overshoot and strong disturbance inhibition compared with PID controller. Thus, the research result is of important guidance for engineering of water level control.

The pump house constant pressure fuzzy self-tuning PID control system simulation

Constant pressure water supply system is a complex time-delay system which makes it difficult to ensure the good control performance and fast response in the working condition for traditional PID control. This paper presents a speed control system of constant pressure pump unit based on fuzzy self-tuning PID control strategy which can realize parameter tuning of PID real-timely. According to a real pumping station, a simulation model is established based on Matlab/Simulink. The simulation result shows that the fuzzy self-tuning PID controller possesses better rapidity of response, shorter adjusting time, and higher steady precision compared with traditional PID controller. Furthermore, fuzzy self-tuning PID control system has no overshoot and strong robustness. Thus, it is to be a good solution to complex pump-delay system problems.

Variable Universe fuzzy control of maximizing the wind engergy for a DFIG

Based on Variable Universe fuzzy control technology with good adaptive and robust capability, a new excitation control strategy for DFIG(doubly fed induction generator) without accurate generator mathematical model is proposed in this paper. Full fuzzy excitation control model is established and analyzed in detail. the whole wind generation system model Was established, simulation results indicate that the proposed methods is efectiveness for maintaining optimum power operating, even during generation system characters varying.

Simulation study of two-order Large Inertia and time-delay system based on active disturbance rejection controller

PID controller can not perform well in two-order large Inertia and time-delay system. ADRC is a new control technique which possesses special advantages for large Inertia and time-delay system. Moreover, ADRC overcomes lots of defects of PID control and improves control performance greatly. Two-tank liquid system — the research object in this paper is a typical two-order large Inertia and time-delay system. In the research an ADRC is designed by using control technique of active disturbance rejection and by comparing with PID controller. Simulation research shows that liquid level control system possesses good rapidity and little overshooting with ADRC and can inhibit strong disturbance. Thus, the research result is of important guidance for engineering of liquid level control.