STRING FAILURE DETECTION FOR LARGE SCALE PHOTOVOLTAIC SYSTEM BY USING NAMEPLATE VALUE AND MEASURED STRING CURRENT AND MODULE VOLTAGE

Abstract

In large-scale PV systems, remote monitoring is conducted in order to reduce the cost of on-site inspection. We propose a remote strings fault detection method for PV systems. By measuring the string current and module voltage of each strings, the proposed method can detect fault such as partial disconnection in the string. The current / voltage measured at the power conditioner and the threshold value obtained by simulation are used for detection. We verified the accuracy of proposed method using an actual large scale PV system in Japan and detected a string that may contain a malfunctioning module.