@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.}
}
@article {68,
	title = {Variable structure control of a photovoltaic energy converter},
	journal = {Control Theory and Applications, IEE Proceedings -},
	volume = {149},
	year = {2002},
	month = {Jul},
	pages = {303-310},
	abstract = {<p>The variable structure control of a DC-to-DC converter in photovoltaic applications is presented. The feasibility of establishing stable constant-voltage and constant-current sliding modes is stressed. Further, their ability to satisfy the control objectives, i.e. maximum power tracking or power regulation, is analysed. In addition, different control laws are obtained by combining these sliding motions, thereby improving their individual performances. The capability of these control laws to steer the state trajectories towards the sliding surfaces from any initial condition, as well as the stability of the sliding regimes, is investigated</p>
},
	keywords = {constant-current sliding modes, constant-voltage sliding modes, DC-DC power convertors, DC-to-DC converter, maximum power tracking, photovoltaic energy converter, photovoltaic power systems, power convertors, power regulation, state trajectories, Variable structure control, variable structure systems},
	issn = {1350-2379},
	doi = {10.1049/ip-cta:20020556},
	url = {http://ieeexplore.ieee.org/xpl/abstractAuthors.jsp?arnumber=1039154},
	author = {De Battista, Hern{\'a}n and Mantz, Ricardo J.}
}
