A Study Regarding Failure Detection for String Monitoring System in Photovoltaics

—Field Trial in F Onomichi Photovoltaic Power Plant—

Abstract

Solar power business has been expanding rapidly in Japan since new feed-in tariff began in July 2012. Generally, monitoring for failure detection and total electric generating capacity is done at power conditioning system (PCS) in large scale photovoltaic (PV) power plant. Although PCS monitoring can detect its own failure or reduction in power generation amount, it is difficult to monitor in PV string/panel. In this paper, new failure detection method available to detect by PV string, by collecting current value of each string measured at each terminal and by analyzing these data is proposed. The data collection is done utilizing DECT (Digital Enhanced Cordless Telecommunications) wireless communication method realizing easy installation to both existing and new PV power plants. Finally, the effectiveness of this proposed method is shown in the demonstration experiments using actual F Onomichi PV power plant.