LMMN-Based Adaptive Control for Power Quality Improvement of Grid Intertie Wind–PV System

Abstract

A new topology comprising of wind-turbine-driven synchronous generator (SG) and solar photovoltaic (PV) array for renewable energy harvesting is proposed in this paper. The stochastic inputs for the proposed system are agitated using nonlinear time-dependent parameters such as varying wind speed and changing solar insolation. The speed variations are absorbed using back-to-back interfaced power electronic converters (PECs), namely, SG side converter (SGC) and utility grid side converter (UGC) with a common dc link where a solar PV array is tied directly. The power injection into the utility grid is leveled by the optimal utilization of the PECs. The SGC uses vector control (VC) for speed control of the SG and maintains unity power factor (UPF) at stator terminals. UGC acquires its switching pulses with proper application of least mean mixed-norm (LMMN) control technique. The new application of LMMN control scheme is used for the compensation of harmonics and for the extraction of fundamental load component. The dc-link voltage is regulated using a proportional integral controller. A prototype is developed and tested under different conditions of sudden changes in load, wind-velocity variations, and varying solar PV insolation. The power sharing scheme proves to be effective. The power quality issues are also addressed and mitigated effectively. The performance is exhibited for the validation of the proposed system and its control.