Algorithms to Estimate the Temperature and Effective Irradiance Level over a Photovoltaic Module using the Fixed Point Theorem

The purpose of this paper is to present four the weather conditions [7]. algorithms to calculate the effective irradiance level, Ei and In addition to the solar irradiance, the temperature can affect temperature, T, of operation for a photovoltaic module, PVM. the output of a PVM. The average temperature for a PVM The main reasons to develop these algorithms are for monitoring should be measured using multiple thermocouples attached climate conditions, the elimination of temperature and solar to be reasured As multipl e thermocouples irradiance sensors, reductions in cost for a photovoltaic inverter to the rear surface [14]. As advantages, the thermocouples system, and development of new algorithms to be integrated can measure a wide range of temperatures and are cheap with maximum power point tracking algorithms. The first three and standard devices in the industry [15]. Thermocouples in algorithms use only the short circuit current, open circuit voltage, photovoltaic applications are used mainly for safety reasons the operating current and voltage for the PVM, avoiding the . . use of pyranometers and thermocouples. The last algorithm can monitoring the average temperature variaions in a PVM [7]. estimate the irradiance level using only the open circuit voltage The main disadvantages using thermocouples are limitations and the PVM temperature of operation. Finally, simulations and in the range of accuracy, noise, connection problems, decaliexperimental results are presented in the paper. bration [15] and the positioning over the surface of the PVM, where it can affect the PVM performance, or under the PVM,

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