A Study on Voltage Fluctuation and Transmission Loss in a Single-Machine Infinite-Bus System with High Penetration of Inverter-Interfaced Power Generation

Abstract

Recently, the installed capacity of inverter-based resources (IBR), such as photovoltaic and wind power generations, has been sharply increasing in power systems across the world. The increase causes concerns on the increases of voltage fluctuations and transmission losses in a power system. The paper examines the voltage fluctuations and transmission losses due to the increases of IBR for a single-inverter infinite-bus system by focusing the maximum reverse power flow received by the infinite-bus. It derives the relations between the voltage of the inverter and the power received at the infinite bus in addition to that between the voltage and output of the inverter. The results show that, when the inverter power is to be increased, the power received at the infinite bus reaches the maximum before the inverter power gets the maximum. Numerical studies reveal that the short-circuit ratio (SCR) corresponding to the maximum power received at the infinite bus is about 1.5 to 3.0, which coincide with empirical value for SCR, for the system adapting the inverter power factor control proposed by the authors.