Evaluation of power generation performance using only the nameplate value using linear interpolation method

Abstract

The standard test condition (STC) is defined as the measurement condition to accurately measure the power generation performance of solar module. Each photovoltaic (PV) module has nameplate values defined under STC. PV module can be measured indoor under STC, but it is difficult to measure under STC in outdoors, because the output power of PV module is greatly affected by solar radiation and temperature. In this study, I-V curves under STC and dark conditions were calculated by using only nameplate values. Irradiance, module temperature and these I-V curves are used for drawing reference I-V curve. One diode model equation was used for the calculation of these I-V curves. This paper used PV Module irradiance Sensor (PVMS) in outdoor experiment. By using calculated I-V curves, linear interpolation method and temperature correction were applied in order to create reference I-V curve to the experimental condition. The I-V curve after temperature correction was used as a reference. Then, reference I-V curve was compared with experiment values in outdoor as the correct value. The power generation performance of the PV module is evaluated by two curves error. Three conditions of irradiances between high irradiance and low irradiance were selected as experimental conditions. As a result, reference I-V curve was calculated about within 3% precision.