Robust coordinated control using backstepping of flywheel energy storage system and DFIG for power smoothing in wind power plants

Abstract

<p>This paper presents a robust coordinated control of a flywheel energy storage system (FESS) and a doubly fed induction generator (DFIG) based wind energy conversion system (WECS), used to smooth the wind induced output power fluctuations. The overall system control combines field oriented control schemes and nonlinear backstepping approach applied first, to the machine side converter (MSC) to regulate the DFIG active and reactive power in order to ensure maximum power point tracking (MPPT) operation and a unity power factor at the point of common coupling (PCC). Then, to the grid side converter (GSC) to maintain a constant DC bus voltage. Finally, to the flywheel side converter (FSC) in way that allows the storage unit to serve as a buffer that stores energy in the case of excess power and retrieves it back into the output in the case of power deficiency. A numerical simulation using Matlab/Simulink software validates the effectiveness of the proposed control strategies in terms of dynamic response, improvement of generated power quality and robustness against parametric variation.</p>

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“…It can be observed that the current waveforms have also been modified due to the addition of the two sinusoidal components with different frequencies. Unlike the stator overcurrent, which can be tolerated by the machine thermal capacity, the overcurrent in the rotor terminals could damage the power electronic interfaces, normally designed to carry only around one-third of the generator rated power [20]. Figure 12 shows the overvoltage induced at the DC bus capacitor during the fault.…”

Accurate battery model parameter identification using heuristic optimization

“…The justification for selecting these three algorithms is due to their wide applicability and readily to be implemented in Matlab. These algorithms also have been proven to deliver good optimization accuracy, particularly in battery storage application in renewable energy sources [7,12,13,[21][22][23].…”

A wind turbine sensorless automatic control systems, analysis, modelling and development of IDA-PBC method

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