Wind-Driven DFIG–Battery–PV-Based System With Advance DSOSF-FLL Control

Abstract

In this article, a wind-driven doubly fed induction generator (DFIG), battery, and photovoltaic (PV) array-based system with advanced discrete second-order sequence filter-frequency locked loop control for grid-side converter (GSC) is presented. The improved grid-side control provides the reactive power demand of load connected at the point of common coupling. The GSC control provides active and reactive power sharing and mitigates the power quality issues at unbalanced and nonlinear load conditions. Moreover, it gives a satisfactory performance during the dynamic wind speeds and load variation. The maximum wind power is extracted using the tip speed ratio algorithm. The necessary quantity of reactive power for DFIG is delivered by the rotor-side converter (RSC). The battery with a bidirectional converter is connected to the common dc link of the DFIG. The battery is used to maintain the dc-link voltage between RSC and GSC and it stores the power in light-load conditions. It provides the load demand during lower wind speed and solar irradiation. The maximum solar power is extracted by well-established incremental conductance (InC) algorithm, which provides optimum performance during the high dynamic variation of solar irradiation. Moreover, the InC algorithm increases the system's stability and reduces costs. It is easy to implement and handle nonlinearity. The feedforward PV component is added with the active load current component to improve the dynamic behavior of the system. Simulated and test results show the performance of the developed system in different dynamic conditions, such as load unbalancing, changes in PV insolation, and change in speed from the cut-in to cut-out speeds of the wind turbine. Moreover, obtained results show the battery behavior during different dynamic conditions.