Power Control Design for Variable-Speedwind Turbines (original) (raw)

Control of Variable Speed Variable Pitch Wind Turbine at Above and Below Rated Wind Speed

Journal of Wind Energy

The paper presents a nonlinear approach to wind turbine (WT) using two-mass model. The main aim of the controller in the WT is to maximize the energy output at varying wind speed. In this work, a combination of linear and nonlinear controllers is adapted to variable speed variable pitch wind turbines (VSVPWT) system. The major operating regions of the WT are below (region 2) and above rated (region 3) wind speed. In these regions, generator torque control (region 2) and pitch control (region 3) are used. The controllers in WT are tested for below and above rated wind speed for step and vertical wind speed profile. The performances of the controllers are analyzed with nonlinear FAST (Fatigue, Aerodynamics, Structures, and Turbulence) WT dynamic simulation. In this paper, two nonlinear controllers, that is, sliding mode control (SMC) and integral sliding mode control (ISMC), have been applied for region 2, whereas for pitch control in region 3 conventional PI control is used. In ISMC,...

Systematic approach for PID controller design for pitch-regulated, variable-speed wind turbines

1998 ASME Wind Energy Symposium, 1998

Variable-speed, horizontal axis wind turbines uSe blade-pitch control to meet specified objectives for three regions of operation. This paper focuses on controller design for the constant power production regime. A simple, rigia non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired, The robust nature of the proportional-integralderivative (PD) controller is illustrated, and optimal operating conditions are determined. Became numerous simulation runs may be completed in a short time, the relationship of the two opposing metrics is easily visualized.

Pitch Angle Control of Variable Speed Wind Turbine

The aim of this study is to design a simple controller to maximize the extracted energy of wind turbines. In this study the pitch angle control of variable speed wind turbine is investigated. In particular, it concentrates on the extraction of maximum available energy, reduction of torque and output power variations, which gives stresses in the gearbox and mechanical structure. The control concentrates on separate wind speed internals as well as on whole wind speed region. It is found that the control structures varies substantially between the wind speed regions. Two different control systems are compared. The results show that pitch actuator with three levels of pitching speed have better response.

Systematic Controller Design Methodology for Variable-Speed Wind Turbines

Wind Engineering, 2000

Variable-speed, horizontal axis wind turbines use blade-pitch control to meet specified objectives for three regions of operation. This paper provides a guide for controller design for the constant power production regime. A simple, rigid, non-linear turbine model was used to systematically perform trade-off studies between two performance metrics. Minimization of both the deviation of the rotor speed from the desired speed and the motion of the actuator is desired. The robust nature of the proportional-integral-derivative controller is illustrated, and optimal operating conditions are determined. Because numerous simulation runs may be completed in a short time, the relationship between the two opposing metrics is easily visualized. Traditional controller design generally consists of linearizing a model about an operating point. This step was taken for two different operating points, and the systematic design approach was used. The surfaces generated by the systematic design approa...

Nonlinear Power Control Strategies for Variable- Speed Wind Turbines

International Journal of Renewable Energy Research, 2017

These last years, several important researches are about the controls of a variable-speed wind turbines. The objectives of these controls are the optimization of power in the zone of lows winds and the regulation of the power in the zone of intense winds and reduction of the mechanical constraints applied to the wind turbines. The productivity of the wind turbines is limited by available linear controls. In this paper, we will have developed nonlinear controls that satisfy the control objectives of variable-speed wind turbines. The nonlinear controls are tested and compared between them for lows and intense winds. The simulation results on Matlab software show that the nonlinear controls satisfy the desired objectives.

Maximizing the performance of variable speed wind turbine with nonlinear output feedback control

Procedia Engineering, 2012

In this paper, the problem of designing an output feedback regulation control scheme of variable speed wind energy conversion system with rotor speed measurement is addressed. The controller consists of the combination of a linear control for blade pitch angle with a nonlinear H ∞ torque control and a finite-time convergent Super-Twisting Observer. This strategy does not use the wind velocity and avoid the chattering phenomena. The nonlinear H ∞ torque control take into account the nonlinear dynamic aspect of the wind turbine and the turbulent nature of the wind, also mitigate the effects of external disturbances that occur at the input and output of the system. The controller exhibits better power and speed regulation when compared to classic linear controllers. In order to validate the mathematical model and evaluate the performance of proposed controller, we used the National Renewable Energy Laboratory (NREL) aerolastic wind turbine simulator FAST. Simulation and validation results show that the proposed control strategy is effective in terms of power and speed regulation.

Modeling and control of a variable speed variable pitch angle prototype wind turbine

2013

This paper focuses on modeling, control and simulation of a 500 horizontal axis prototype wind turbine that is being developed in the context of the MILRES (National Wind Energy Systems) Project in Turkey. The prototype turbine is designed as variable speed variable pitch angle wind turbine due to its advantages in efficiency and the structure. Aerodynamic, mechanical and electrical subsystems along with pitch and torque controllers are designed in both Matlab/Simulink and S4WT simulation environments. The main control purpose is to generate a power curve that is close to the ideal power curve where the energy efficiency is maximized below the nominal wind speed of 11 / and the power is limited to the nominal value above the nominal wind speed. Turbsim is integrated with both environments to generate a realistic wind profile of Kaimal turbulence model. The performance analysis of the prototype turbine is done under the power production scenario in both environments. Start up, emergency stop, shut down and parked scenarios are also implemented in S4WT.

The Modeling and Dynamic Characteristics of a Variable Speed Wind Turbine

In this paper, a functional structure of a wind energy conversion system is introduced, before making a comparison between the two typical wind turbine operating schemes in operation, namely constant-speed wind turbine and variable-speed wind turbine. In addition, the modeling and dynamic behavior of a variable speed wind turbine with pitch control capability is explained in detail and the turbine performance curves are simulated in the MATLAB/simulink.