Gradual Faults Diagnosis by a Novel Impedance Characterization Method

摘要

This paper presents a novel photovoltaic impedance characterization method aiming to evaluate the state and gradual decrease of photovoltaic (PV) panel health. The big challenge to meet for the PV panels is to guarantee their robust and reliable functioning, and specially maintain their efficient yield as long as possible, which imply that a real-time diagnose is mandatory to detect rapidly the faults that may occur on PV plants and then react effectively. This study developed a novel method that allows not only to detect, locate and recognize the type of PV defects on an already installed PV plant, but also to measure the discordance between the manufacturer PV datasheet and the real performance of the PV panel once received from the supplier. The impedance characterization is a new analytical and criterion method that uses the Photovoltaic Plant Reflectometry Profile (PPRP) in order to measure exactly any discordance between an ideal state PV module and a defective one, and, even detect multiple faults in a string of connected PV modules. Simulation results show that the proposed method is a valid one that detects any type of PV faults.