# A Decentralized Wireless Solution to Monitor and Diagnose PV Solar Module Performance Based on Symmetrized-Shifted Gompertz Functions

## TL;DR

A wireless system monitors solar panels using low-cost sensors and a mathematical model to track performance in real time.

## Contribution

A decentralized wireless monitoring system using symmetrized-shifted Gompertz functions for real-time PV module diagnostics.

## Key findings

- The system uses low-cost sensors and wireless networks for real-time PV monitoring.
- Symmetrized-shifted Gompertz functions accurately model expected PV performance.
- The solution was successfully implemented in a Spanish grid-connected PV power plant.

## Abstract

This paper proposes and assesses an integrated solution to monitor and diagnose photovoltaic (PV) solar modules based on a decentralized wireless sensor acquisition system. Both DC electrical variables and environmental data are collected at PV module level using low-cost and high-energy efficiency node sensors. Data is real-time processed locally and compared with expected PV module performances obtained by a PV module model based on symmetrized-shifted Gompertz functions (as previously developed and assessed by the authors). Sensor nodes send data to a centralized sink-computing module using a multi-hop wireless sensor network architecture. Such integration thus provides extensive analysis of PV installations, and avoids off-line tests or post-processing processes. In comparison with previous approaches, this solution is enhanced with a low-cost system and non-critical performance constraints, and it is suitable for extensive deployment in PV power plants. Moreover, it is easily implemented in existing PV installations, since no additional wiring is required. The system has been implemented and assessed in a Spanish PV power plant connected to the grid. Results and estimations of PV module performances are also included in the paper.