Microcontroller Based Low Cost and Modular Architecture for Photovoltaic Array Monitoring

This paper presents the architecture and characteristics of a low cost system to monitoring operation variables associated to an 1.68kW PV generator located in the Electrical and Electronics Engineering School at Universidad del Valle, in Cali-Colombia. The monitoring system is composed by Measurement Modules (MMs) connected to a personal computer through a RS-485 bus in a master-slave architecture. Each MM receives voltage, current, irradiance and temperature measurements of PV modules. The system is designed to allow increase the number of MMs, adjusting to the necessities in case that the PV generator is enlarged.

I. Introduction

The installation of PV systems has experienced an increase in the last decade. By the end of 2016, global installed capacity was at least 303 GW [1]. This has made it necessary to evaluate the operation of PV modules in several conditions, to overcome the vulnerability to aging and failures due to various factors, such as mismatching conditions, harsh operating environmental conditions, and so on [2]. Facing these problems requires carrying on researching activities based on information collected about performance of the PV system, therefore monitoring systems are needed.