Stabilization of a power system by a distributed generation using the synchronization inverter

Abstract

More and more distributed generators (DGs) using inverters are being connected to power systems. However, DGs with a conventional inverter do not have synchronizing power. As DGs, especially photovoltaic generators (PVs) grow at this rate, power system will become unstable, because of the shortage of synchronizing power. The purpose of this study is to improve stability of power systems with DGs. In this paper, we propose a "Synchronization Inverter", which has a synchronizing power similar to that of a synchronous generator and its control equipment. This inverter is operated according to the control method based on a swing equation, a governor control logic and a power equation. We investigated the stability of power system with DGs by simulation, and compared conventional inverter with the Synchronization Inverter. As a result, when a Synchronization Inverter was introduced into a power system with DGs as a substitute for the conventional inverter, the stability of the power system improved.