A unified test and evaluation of PCS on the market for residential PV application in Japan

The operating characteristics of representative PCSs (power conditioning sub systems) on the market in Japan were tested and evaluated, to make use of the high performance design of PV (photovoltaic) systems for 400 to 600 residences that are being established as the new town of Josai-no-mori in the Ota-city, Gunma prefecture in Japan. Especially, the reliability of islanding protection of PCSs for PV application was clarified. It was proved that there were no problems with respect to the power quality and stable operation of most PCSs in Japan. However, regarding the safety, a part of PCS shows the dangerous inclination that continues the islanding phenomenon easily. Therefore, it is necessary to pay attention to PV site design in terms of protection system against islanding phenomenon.