Power management with power quality enhanced operation in off-grid hybrid power systems

Hybrid power systems are considered as a reliable and viable option for the electrification of rural villages which are beyond the reach of grid electricity. Many such renewable based off-grid power systems working mostly in India and Africa are generating power which are not at par with grid power. The control of power among different renewable sources while maintaining the power quality of supply, is important for the reliable and sustainable operation of these off grid systems. This paper proposes a power sharing scheme using instantaneous symmetrical component theory (ISCT) among two parallel inverters and a biomass gasifier engine alternator (BGEA). In the proposed scheme, the reactive, harmonic and unbalance in the load power are always supplied by one photovoltaic (PV) inverter, while the active power is shared between two inverters and a biomass gasifier engine. This power sharing control increases the power reliability and power quality of village hybrid power systems. A simulation study of the proposed system has been carried out and the results are presented.