Hydro/PV Hybrid Power System with New Control Strategy to Mitigate the Voltage Disturbances

Abstract

This paper presents a new control strategy for grid integrated hydro/PV hybrid system. Under grid connected mode, the control strategy will work as a constant current controller (CCC) to inject the specific quantity of power generated by micro-grid system and provide robust tracking of generated active and reactive power trajectories. As the fault transpires in electrical power system, the power grid must be disconnected from rest of the micro-grid system to avoid potential hazard and this situation is identified as islanding. In islanding mode of operation, the proposed control strategy switch to constant voltage controller (CVC) for maintaining constant voltage at the point of common coupling (PCC) to feed local sensitive load. The hydro and PV systems are considered in this paper as micro-grid system, which are hybridized for injecting generated power to main grid. The transient and steady state analysis, stability analysis of the proposed grid integrated hybrid system is performed to realize the improved performance of the system. The harmonic analysis is also done to prove the improved power quality of the system. The presented results clearly indicates the control strategy has full control over the active and reactive power flow to/from the hybrid system and proposed system is more effective, reliable, less complex, have higher power quality and better dynamic performance under most severe fault conditions.