Power Quality Improvement in SyRG-PV-BES-Based Standalone Microgrid Using ESOGI-FLL-WIF Control Algorithm

In this article, a resilient enhanced second-order generalized integrator with frequency locked loop and inner loop filter (ESOGI-FLL-WIF) control algorithm is implemented to enhance the power quality and to regulate the voltage/frequency of a microgrid. This control has a simple structure, fast convergence, and excellent dynamic and steady-state response. The ESOGI-FLL-WIF control algorithm is used for assessing the fundamental constituent from harmonics and dc bias infected current. ESOGI-FLL-WIF control strategy tracks the frequency and tunes to the frequency fluctuations in transient situations. To have a fair comparison, the performance of the ESOGI-FLL-WIF control algorithm is compared with already existing controls. This three-phase four-wire islanded system consists of a solar photovoltaic array and pico-hydro turbine-driven synchronous reluctance generator (SyRG). As an alternative to the conventional generators, SyRG is used because it is economical (no permanent magnets in the rotor) and has high efficiency (no electrical losses in the rotor). The four-leg converter compensates neutral current and controls the reactive power injection under unbalance load condition, whereas for active power management, battery energy storage is incorporated in the system. A prototype of the system is developed and tested under different situations of load unbalancing and solar insolation change to confirm the effectiveness and viability of the control strategy.