Diagnosis photovoltaic failure by simple function method to acquire I–V curve of photovoltaic modules string

PV module or a cluster of module failure leads to lower the generating time rate and decrease its power amount. Detection and repair are apprehended to be the constructor's burden. This study aims to constitute the diagnosis function and system. In the future, this mechanism assumes to detect some faults and failures automatically. This method enables to acquire I-V curves of PV modules strings; each I-V curve is divided into two areas. One area is Voltage dependent areas, which voltage varies less, to combine the input capacitance inside of a power conditioner and the variable DC power. This configuration enables to reduce DC power capacity. The other area is Current dependent. I-V characteristic is obtained in each two areas and connected. Consequently, I-V curve of all part is acquired without preventing PV generation from suspension a little. The measurement function and method were investigated and performed. The availability is confirmed to acquire I-V curve for diagnosis detection.