Operation reference status selection for photovoltaic arrays and its application in status evaluation

Abstract

In the context of rapid development of photovoltaic (PV) power generation, as an aspect of the key equipment that undertakes the photoelectric conversion in PV power plants, the operation status of PV arrays directly affects the power generation efficiency and economic benefits of PV power plants. An accurate evaluation of the PV array operation status can quickly locate operational weak points and provide the benchmark array for fault diagnosis, which has important engineering application value. So, a new method for selecting the operating reference status of PV arrays is proposed in the paper. First, the array Performance Ratio (PR) probability distribution model was established using the non-parametric estimation method, and the comprehensive evaluation indicators of the PV array were determined using the model characteristic indices and output power of the PV array. The technique for order preference by similarity to ideal solution (TOPSIS) method was improved, the reference PV array was selected, and a graded evaluation of the operation status of the PV arrays was designed. This study provides a novel method to evaluate the operation status of PV arrays from the perspectives of power deviation and stability. The effectiveness of the proposed method was verified through empirical analysis.