International audienceThis paper deals with the power generation control in variable-speed wind turbines. These systems have two operation regions which depend on wind turbine tip speed ratio. A high-order sliding-mode control strategy is then proposed to ensure stability in both operation regions and to impose the ideal feedback control solution in spite of model uncertainties. This control strategy presents attractive features such as robustness to parametric uncertainties of the turbine. The proposed slidingmode control approach has been validated on a 1.5-MW threeblade wind turbine using the National Renewable Energy Laboratory wind turbine simulator FAST (Fatigue, Aerodynamics, Structures, and Turbulence) code. Validation results show that the proposed control strategy is effective in terms of power regulation.Moreover, the sliding-mode approach is arranged so as to produce no chattering in the generated torque that could lead to increased mechanical stress because of strong torque variations
This paper addresses the problem of controlling power generation in variable-speed wind energy conversion systems (VS-WECS). These systems have two operation regions depending on the wind turbine tip-speed ratio. They are distinguished by minimum phase behavior in one of these regions and a nonminimum phase in the other one. A sliding mode control strategy is then proposed to ensure stability in both operation regions and to impose the ideal feedback control solution despite model uncertainties. The proposed sliding mode control strategy presents attractive features such as robustness to parametric uncertainties of the turbine and the generator as well as to electric grid disturbances. The proposed sliding mode control approach has been simulated on a 1.5-MW three-blade wind turbine to evaluate its consistency and performance. The next step was the validation using the National Renewable Energy Laboratory (NREL) wind turbine simulator called the fatigue, aerodynamics, structures, and turbulence code (FAST). Both simulation and validation results show that the proposed control strategy is effective in terms of power regulation. Moreover, the sliding mode approach is arranged so as to produce no chattering in the generated torque that could lead to increased mechanical stress because of strong torque variations. Index Terms-Power generation control, sliding mode control, wind energy conversion system. NOMENCLATURE B g Generator external stiffness (newton meter/radian second). B r Rotor external stiffness (newton meter/radian second). C p (λ) Power coefficient. C q (λ) Torque coefficient. J g Generator inertia (kilogram meter 2). J r Rotor inertia (kilogram meter 2). K g Generator external damping (newton meter/radian second). K r Rotor external damping (newton meter/radian second). n g Gearbox ratio. P a Aerodynamic power (watt). P g Generated power (watt). R Rotor radius (meter).
Abstract-This paper deals with power extraction maximization of a doubly fed induction generator (DFIG)-based wind turbine. These variable speed systems have several advantages over the traditional wind turbine operating methods, such as the reduction of the mechanical stress and an increase in the energy capture. To fully exploit this latest advantage, many control schemes have been developed for maximum power point tracking (MPPT) control schemes. In this context, this paper proposes a second-order sliding mode to control the wind turbine DFIG according to references given by an MPPT. Traditionally, the desired DFIG torque is tracked using control currents. However, the estimations used to define current references drive some inaccuracies mainly leading to nonoptimal power extraction. Therefore, using robust control, such as the second-order sliding mode, will allow one to directly track the DFIG torque leading to maximum power extraction. Moreover, the proposed control strategy presents attractive features such as chattering-free behavior (no extra mechanical stress), finite reaching time, and robustness with respect to external disturbances (grid) and unmodeled dynamics (generator and turbine). Simulations using the wind turbine simulator FAST and experiments on a 7.5-kW real-time simulator are carried out for the validation of the proposed high-order sliding mode control approach.Index Terms-Control, doubly fed induction generator (DFIG), second-order sliding mode (SOSM), wind turbine (WT).
This paper deals with the fault ride-through capability assessment of a doubly fed induction generator-based wind turbine using a high-order sliding mode control. Indeed, it has been recently suggested that sliding mode control is a solution of choice to the fault ride-through problem. In this context, this paper proposes a second-order sliding mode as an improved solution that handle the classical sliding mode chattering problem. Indeed, the main and attractive features of high-order sliding modes are robustness against external disturbances, the grids faults in particular, and chattering-free behavior (no extra mechanical stress on the wind turbine drive train). Simulations using the NREL FAST code on a 1.5-MW wind turbine are carried out to evaluate ride-through performance of the proposed high-order sliding mode control strategy in case of grid frequency variations and unbalanced voltage sags.
This paper deals with power extraction maximization and grid fault tolerance of a Doubly-Fed Induction Generator (DFIG)-based Wind Turbine (WT). These variable speed systems have several advantages over the traditional wind turbine operating methods, such as the reduction of the mechanical stress and an increase in the energy capture. To fully exploit this latest advantage, many efforts have been made to develop Maximum Power Point Tracking (MPPT) control schemes. In this context, this paper proposes a highorder sliding mode control. This control strategy presents attractive features such as chattering-free behavior (no extra mechanical stress), finite reaching time, and robustness with respect to external disturbances (grid) and unmodeled dynamics (DFIG and WT). It seems also well adapted for grid disturbance tolerance. The proposed high-order sliding mode control approach has been validated on a 1.5-MW three-blade wind turbine using the wind turbine simulator FAST. Index Terms-Wind turbine, Doubly-Fed InductionGenerator (DFIG), power generation, grid fault, high-order sliding mode. NOMENCLATURE DFIG = Doubly-Fed Induction Generator; WT = Wind Turbine; HOSM = High-Order Sliding Mode; MPPT = Maximum Power Point Tracking; v = Wind speed (m/sec); ρ = Air density (kg/m 3 ); R = Rotor radius (m); P a = Aerodynamic power (W); T a = Aerodynamic torque (Nm); λ = Tip speed ratio; C p (λ) = Power coefficient; ω mr = WT rotor speed (rad/sec); ω mg = Generator speed (rad/sec); T g = Generator electromagnetic torque (Nm); J t = Turbine total inertia (kg m 2 ); K t = Turbine total external damping (Nm/rad sec); s, (r) = Stator (rotor) index; d, q = Synchronous reference frame index; V (I) = Voltage (Current); P (Q) = Active (Reactive) power; φ = Flux; T em = Electromagnetic torque; R = Resistance; L (M) = Inductance (Mutual inductance); σ = Leakage coefficient, σ = 1 -M 2 /L s L r ; θ r = Rotor position; ω r (ω s ) = Angular speed (Synchronous speed); s = Slip; p = Pole pair number.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.