The characteristics of wind turbine systems such as nonlinearity, uncertainty and strong coupling, as well as external interference, present great challenges in wind turbine controller design. In this paper, a quasi-continuous high-order sliding mode method is used to design controllers due to its strong robustness to external disturbances, unmodeled dynamics and parameter uncertainties. It can...

This paper presents a novel type of variable speed wind turbine with a new drive train different from the variable speed wind turbine commonly used nowadays. In this concept, a synchronous generator is directly coupled with the grid, therefore, the wind turbine transient overload capability and grid voltage support capability can be significantly improved. An electromagnetic coupling speed regu...

A power criterion for selecting the electric motor used in a gas turbine emulator is defined. The power criterion is derived in terms of the ratio of inertias between the gas turbine engine and the electric motor, rotational losses and load torque. The gas turbine emulator allows emulating the speed-torque behavior of a gas turbine engine. Using simulation models, we show that the steady-state ...

Many challenges exist for the operation of wind turbines in an efficient manner that is reliable and avoids component fatigue and failure. Turbines operate in highly turbulent environments resulting in aerodynamic loads that can easily excite turbine structural modes, possibly causing component fatigue and failure. Wind turbine manufacturers are highly motivated to reduce component fatigue and ...

A new composite turbine control architecture that consists of feedforward and feedback parts based on the upwind speed measurements and wind speed measurements at the turbine site, respectively, is described. The algorithm starts with preprocessing of a low-rate sampled upwind speed via the spline interpolation method. A run-ahead model driven by the signals from a preprocessing block models th...

A variable-speed, constant-pitch wind turbine was investigated to evaluate the feasibility of constraining its rotor speed and power output without the benefit of active aerodynamic control devices. A strategy was postulated to control rotational speed by specifying the demanded generator torque. By controlling rotor speed in relation to wind speed, the aerodynamic power extracted by the blades...

A numerical study of the dynamic behaviour of a turbine meter measuring solid flowrate was carried out by use of the discrete element method. The simulation was conducted with a cylindrical standpipe of 30d in diameter and 40d high, filled with 30000 mono-sized spheres of diameter d, and with a turbine fixed at the centre of the standpipe at a height of 20d. The variations of the torque and rot...

Modern wind turbines are designed in order to work in variable speed operations. To perform this task, wind turbines are provided with adjustable speed generators, like the double feed induction generator. One of the main advantage of adjustable speed generators is improving the system efficiency compared to fixed speed generators, because turbine speed can be adjusted as a function of wind spe...

A steam turbine, heart of all refineries. This work presents the mathematical modelling of the steam turbine unit in isolated operating condition, based on the continuity equation including servomotor for actuation purpose. Steam turbine should run at a constant speed for its safe operation and frequency stability. Adaptation of different controller like Feedback, PI, PID using certain adaptati...

This research deals with investigations on the “Active Generator” under rotor speed variations and output frequency control. It runs at turbine speed and it is connected to a three phase electrical power grid which has its own frequency different from turbine frequency. In this regard the set composed of a four phase synchronous generator and a natural commutated matrix converter (NCMC) made wi...