Novel Quick Backup Function for Dispersed Power Source Employing AC/DC Converter

Abstract

In this paper, the authors present the system configuration and control scheme of a dispersed power source equipped with quick backup function, which acts as a dispersed power source when there exists no fault in commercial power network and functions as a backup power supply in case of a fault of the network. If a fault, e.g., a voltage interruption occurs on the network, the dispersed power source disconnects critical loads from the network in an instant, and continues supplying power to the loads. We also discuss the method of disconnecting power network sufficiently quick when some fault occurs on the network, adopting non-gate-turn-off devices such as thyristors to the ac interconnecting switches. Since it takes only 2 milliseconds to disconnect the loads from a faulted network, there bring no negative effects on the loads. Simulations and experimental tests are carried out to confirm the practicability of the proposed power source.