Development and Validation of an Autonomous System for Measurement of Sunshine Duration

Abstract

This paper presented an autonomous electronic system for sunshine duration (SD) monitoring based on the contrast method and developed to operate on a horizontal surface. The prototype uses four photoresistors arranged at 90° in a 20 mm diameter circumference separated by a shading structure used to create a shadow pattern on the detection element. Photoresistors are inserted in individual signal conditioning circuits based on the association between Wheatstone bridges and operational amplifiers to provide an analog signal to the microcontroller unit. The determination of SD occurs through the implementation of fuzzy logic with numerical calculation methods to estimate the probability (f) of solar disk obstruction and estimate SD values. The system does not require additional adjustments after installation or use of energy sources for operation due to the use of an internal battery with charge recovery by solar panels. Experimental results of the proposed system were validated with the ones provided by a government meteorology station. Statistical analysis of the results showed a confidence index (c) greater than 90%, with a precision of 94.26%. The proposed system is a feasible low-cost solution to the available commercial systems for the measurement of sunshine duration.

Development of a Real-Time Surface Solar Radiation Measurement System Based on the Internet of Things (IoT)

“…In Brazil, the cost of implementing an essential infrastructure for monitoring solar irradiation has become quite limited for the national radiometric network, affecting the understanding of the behavior and availability of these crucial environmental data. The implementation cost of solar irradiation measurement systems has imposed restrictions as it is a point value [1,[5][6][7][8][9][10].…”

Design of a Real-Time Salinity Detection System for Water Injection Wells Based on Fuzzy Control

“…In the defuzzification stage, the value of u is calculated according to the language description and membership function. The barycenter method was selected from among several calculation methods [ 35 , 36 ]. After defuzzification stage, the range of output u is [0, 7].…”