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.