Adaptive PR and BBO Based Control Strategy of Wind-Solar Integrated Standalone Microgrid for Residential Application

The off-grid village electrification is made viable by utilizing the full potential offered by renewable energy sources (RESs). Integrating more than one resource i.e. wind and solar, offers self-sufficiency of power due to their complementary nature. The intermittency issues raised by RESs are overcome by using a battery as the storage. The battery reduces the uncertainty during demand rise, power deficiency and overloading with its faster response than diesel generators and micro-turbines. This work deals with the wind energy/solar photovoltaic (PV)/battery energy storage (BES) operating in coordinated manner to meet the high power residential loads at village scale. For the required speed regulation of a wind turbine driven generator, the traditional proportional integral (PI) controller is replaced by evolution inspired biogeography based optimization control (BBO) based PI controller. The relevant issues identified by a use of fixed gain PI controller such as, unsuitable regulation due to incorrect tuning are addressed by the use of BBO tuned speed controller providing fine-tuning of the weighting factors. Whereas, in the voltage control, the performance degradation issue of PI controller while dealing with AC quantities, is dealt with adaptive proportional resonant (PR) controller along with disturbance observer based phase locked loop (DO-PLL). The DO control filters the load current component and improves the power quality at point of common coupling (PCC). The battery is deployed through a bidirectional converter, acts as a residential storage for backing up the power firming RESs production. Performance improvement obtained from a laboratory developed test setup verifies the microgrid effectiveness at RESs generation variability and load changes.