Control of Real and Reactive Power using a Novel SVC Feedback System for Load Sharing in Grid Connected PV Power System

Abstract

In a power system of conventional parallel-connected generators, share of real power and reactive var of an incoming generator are controlled by adjusting shaft power input and field excitation. The scenario of load sharing by a grid connected PV system is however different. Since no prime mover or excitation source are present. Due to serious power crisis, there is a need for the transfer of PV power to the grid systems. However, this needs intensive analysis on the load sharing phenomena. In this study, aspects of load sharing of a grid connected PV system utilizing boost inverter are analyzed, and a strategy is proposed where the load sharing task can be undertaken controlling the modulation index of the boost inverter.  We also have briefly surveyed the characteristics of the boost inverter for different voltage levels and prescribed a range of modulation index for which the system can perform perfectly for each of these voltage levels. It is seen that both real power and reactive var are affected upon the change in the modulation index of the boost inverter. Analysis and simulation results are presented to demonstrate effectiveness of the proposed control technique using boost inverte

Keywords

• Boost inverter, PV system, Static Var Compensator(SVC), Modulation index, SPWM bridge inverter.

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