Control of Wind–Diesel Hybrid System With BESS for Optimal Operation

This study presents a wind energy conversion system (WECS) with a diesel generator (DG). The proposed system with its control regulates the loading of DG to achieve a low-specific fuel consumption. The generator used in WECS is a doubly fed induction generator (DFIG). It consists of two voltage-source converters for the system control. The rotor-side converter helps in achieving the maximum power-point tracking of the wind turbine. The generator-side converter (GSC) helps in regulating the DG generation, while maintaining DFIG as well as DG currents balanced and harmonics within the requirement of the IEEE-519 standard for variety of loads. The system envisages an energy storage by connecting a battery bank at the dc bus of DFIG. The battery bank provides a buffer storage. The GSC also provides a path for the surplus or deficient power through the battery bank. The proposed system is modeled using Sim-power-system tool box of MATLAB and its performance results are presented for conditions such as synchronisation of the wind generator, variation of nonlinear and unbalanced loads, and varying wind speeds. Under all these scenarios, the currents flowing through both the generators are balanced. Finally, the effectiveness of the system is demonstrated experimentally on a prototype developed in the laboratory.