A remote control system for scattered grid-connected inverters of photovoltaic system

Abstract

This paper introduces a new method of controlling Anti-island of multiple photovoltaic grid-connected inverters which are scattered in a confined resident area. The main test point of Grid Island is selected at the transformer substation where there is a central remote control system built that testing work situation of transformer. When the switches of the transformer turn off due to some troubles, the central control system can check the information and emits commands that the grid-connected inverters shut down, that means the work situation of island in this area can be stopped. Besides being the central control system, it can also receive signals using modem from separate grid-connected inverters through power carrier wave, which can check any grid connected inverter is connecting or not the power line between grid-connected inverters and the transformer substation of the local. If the central control system does not receive signal from some grid-connected inverters, the central control system will confirm the some part of power line has interrupted from the main grid power line. The central control system then emits commands so that it controls the grid-connected inverters shut down through a wireless remote control. This method is suitable when there are many grid connected inverters installed in the same power line local area and it can detect any island situation at any location. Copyright © (2007) by the International Solar Energy Society.