@article {178, title = {Multiple-input-multiple-output high-order sliding mode control for a permanent magnet synchronous generator wind-based system with grid support capabilities}, journal = {IET Renewable Power Generation}, volume = {9}, year = {2015}, pages = {925-934}, abstract = {This study presents a control design for a grid connected wind energy conversion system based on a gearless PMSG. The generation system structure comprises a three blade turbine, a 2 MW multi-pole PMSG and a full-scale back-to-back frequency converter linked to the utility grid. The proposed control scheme allows following dynamical specifications taking into account operational requirements and ancillary services imposed by the recent grid connection codes, that is, reactive power regulation and fault ride-through (FRT) capabilities. The control actions to be applied during normal grid operation are designed through second-order sliding mode techniques using a two-stage cascade structure. The multi-variable controller designed attains to regulate the active and reactive powers delivered to the grid, minimising the resistive losses into the generator and maintaining important internal variables into the desired range. This controller presents attractive advantages such as robustness against unmodelled dynamics and external perturbations, finite time convergence to the sliding surfaces and chattering mitigation. To endorse the controlled system with FRT capabilities, a switching control scheme based on voltage grid measurements is also proposed. The performance of the whole control approach is analysed through representative simulations which include parameter variations, external perturbations and three-phase voltage dips.}, keywords = {active power regulation, blade turbine, blades, chattering mitigation, control system synthesis, external perturbation, fault ride-through capability, frequency convertors, FRT capability, full-scale back-to-back frequency converter, gearless permanent magnet synchronous generator, grid connected wind energy conversion system, grid support capability, machine control, MIMO systems, multiple-input-multiple-output high-order sliding mode control design, multipole PMSG, multivariable control systems, multivariable controller design, permanent magnet generators, permanent magnet synchronous generator wind-based system, power convertors, power generation control, power generation faults, power grids, power system measurement, reactive power control, reactive power regulation, resistive loss minimization, second-order sliding mode technique, switching control scheme, synchronous generators, variable structure systems, voltage control, voltage measurement, wind power plants, wind turbines}, issn = {1752-1416}, doi = {10.1049/iet-rpg.2014.0417}, author = {Valenciaga, Fernando and Fern{\'a}ndez, Roberto. D.} } @conference {100, title = {Active and reactive power control of a brushless doubly fed reluctance machine using high order sliding modes}, booktitle = {Electrical Machines, 2008. ICEM 2008. 18th International Conference on}, year = {2008}, month = {Sept}, abstract = {

This article develops a decoupled active and reactive power control for a variable-speed constant-frequency (VSCF) power generation system based on a brushless doubly fed reluctance machine. This machine is a forthcoming low cost candidate for applications with limited variable speed requirements such as pumping and wind generation. Basically, it allows the use of a partially rated power electronic converter and, at the same time, offers a reliable and maintenance-free operation because of its brushless feature. The control design is approached through second order sliding mode techniques. This theoretical framework permits to deal with systems described by perturbed nonlinear dynamic models, obtaining simple controllers with a finite time reaching phase and a chattering free behavior. The controller performance is assessed through exhaustive simulations.

}, keywords = {active power control, brushless doubly fed reluctance machine, brushless machines, chattering free behavior, Converters, Costs, high order sliding modes, machine control, perturbed nonlinear dynamic models, Power conversion, power electronic converter, Power electronics, Pumps, reactive power control, reluctance machines, Sliding mode control, variable structure systems, variable-speed constant-frequency power generation system, Wind energy generation, Wind power generation}, doi = {10.1109/ICELMACH.2008.4799959}, url = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=4799959}, author = {Valenciaga, Fernando} } @article {72, title = {Dynamical sliding mode power control of wind driven induction generators}, journal = {Energy Conversion, IEEE Transactions on}, volume = {15}, year = {2000}, month = {Dec}, pages = {451-457}, abstract = {

This paper concerns power regulation of variable-speed wind energy conversion systems. These systems have two regions of operation, depending on the tip speed ratio of the wind turbines. They are distinguished by a minimum phase behavior in one of these regions and a nonminimum phase one in the other. A sliding mode control strategy is proposed that assures stability in both regions of operation and imposes the ideally designed feedback control solution in spite of model uncertainties. Moreover, power regulation by the proposed sliding control in the minimum phase region is completely robust to wind disturbances and parameter uncertainties

}, keywords = {asynchronous generators, Control systems, dynamical sliding mode power control, feedback, ideally designed feedback control solution, Induction generators, machine control, minimum phase behavior, minimum phase region, model uncertainties, nonminimum phase region, parameter uncertainties, Power control, Power generation, power regulation, Power system modeling, Robustness, Sliding mode control, stability, tip speed ratio, variable speed gear, variable structure systems, variable-speed wind energy conversion systems, wind disturbances, wind driven induction generators, Wind energy, Wind energy generation, Wind power generation, wind turbines}, issn = {0885-8969}, doi = {10.1109/60.900507}, url = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=900507}, author = {De Battista, Hern{\'a}n and Mantz, Ricardo J. and Christiansen, Carlos F.} } @article {74, title = {Sliding mode control of wind energy systems with DOIG-power efficiency and torsional dynamics optimization}, journal = {Power Systems, IEEE Transactions on}, volume = {15}, year = {2000}, month = {May}, pages = {728-734}, abstract = {

Wind turbines with double output induction generators can operate at variable speed permitting conversion efficiency maximization over a wide range of wind velocities. However, random wind fluctuations, wind shear and tower shadow, may excite the oscillation mode of the mechanical system, producing large torque ripple. Consequently, damage to drive train components and power quality problems may occur. In this paper, a sliding mode control is developed which provides a suitable compromise between conversion efficiency and torque oscillation smoothing. The resultant sliding dynamics is completely robust to uncertainties in the electrical variables and parameters. In addition, to prevent windup problems due to saturation, a combined sliding surface that incorporates such limitations is proposed

}, keywords = {asynchronous generators, combined sliding surface, conversion efficiency maximization, double output induction generators, drive train components, electrical variables uncertainties, Fluctuations, Induction generators, large torque ripple, machine control, mechanical system, Mechanical systems, oscillation mode excitation, oscillations, Poles and towers, power efficiency, power generation control, Power quality, power quality problems, power supply quality, random wind fluctuations, resultant sliding dynamics, Sliding mode control, Torque, torque oscillation smoothing, torsion, torsional dynamics optimization, tower shadow, uncertainties robustness, variable speed, variable speed gear, variable structure systems, Wind energy, wind energy systems, wind shear, Wind speed, wind turbines}, issn = {0885-8950}, doi = {10.1109/59.867166}, url = {http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=867166}, author = {De Battista, Hern{\'a}n and Puleston, Pablo F. and Mantz, Ricardo J. and Christiansen, Carlos F.} }