Voltage-Dependent Temperature Coefficient of the I–V Curves of Crystalline Silicon Photovoltaic Modules

The temperature dependence of the I-V curves of various kinds of commercial crystalline silicon photovoltaic modules is investigated, based on experiments by using a solar simulator and a thermostatic chamber. The temperature coefficient (TC) of the output voltage of the modules with p-n junction technology is found to closely agree with a formula as a function of their output voltage per cell and temperature, throughout the voltage range of about 0.5-0.7 V per cell, which is important for estimating the Pmax, fill factor, and Vocof the modules. The formula is derived from a one-diode model, and reproduces the TC of the I-V curves within ±5% relative error without adjusting the parameter for each module. The formula is successfully applied for translating the modules' I-V curves.