温度对户外光伏系统发电效率影响分析

光伏模块的发电效率会受到各种因素的影响,其中温度是重要影响因素之一。温度对光伏模块发电效率的影响分析是基于二者之间的线性回归模型进行的,现有研究中通常只考虑辐照、风速、安装结构与位置等因素对模块温度的影响,忽视了晴天持续的高辐照使光伏模块持续工作在高发电状态,产生的热量积累使得模块温度随时间推移而上升的情况。文章通过分析屋顶光伏电厂实测数据,验证了晴天热量积累造成模块温度随时间推移而升高,会对发电效率造成负面影响,雨天的雨水起到为电池板降温的作用,发电效率受到的影响较小;在此基础上,在典型发电效率的多元线性模型中加入时间作为另一个因子,构造更准确的不同天气类型的发电效率模型。

Analysis of Temperature Influence on Efficiency of Outdoor PV system

The power generation efficiency of photovoltaic (PV) module is affected by various factors, and temperature is one of the important factors. The influence of temperature on the efficiency of PV module is analyzed based on the linear regression model between them. The existing researches usually only consider the influences of irradiation, wind speed, installation structure and location on the PV module temperature, and neglect the influence of durative high radiation on the PV module which continues to work in the high power generation state, resulting heat accumulation and the module temperature increment over time. In this paper, it is validated that one of the reasons of PV module temperature increase over time is heat accumulation in sunny days by analyzing the measurement data of roof-mounted PV power plant, which will have negative effect on efficiency. The rain plays the role of cooling solar panels, so that efficiency is less affected. Based on this, time is added as another factor of the typical multivariate linear model of power generation efficiency to construct more accurate models for different weather types.