RULE-BASED ENERGY MANAGEMENT OF A STANDALONE PV-BATTERY SYSTEM UNDER ONE-MONTH SOLAR RESOURCE VARIABILITY: A CASE STUDY IN SENEGAL

Abstract

Energy management is a key factor in the reliability and performance of photovoltaic (PV) systems coupled with battery storage for rural electrification. Unlike studies based on representative days, this work investigates the operation of a PV–battery system over a continuous 28-day period (672 h) to assess the influence of day-to-day weather variations on its behaviour. The system consists of a 36.6 kWp PV generator, a battery storage system (648 Ah, 200 V), and a bidirectional buck–boost converter exchanging energy between the DC bus and the batteries. Simulations were carried out in MATLAB/Simulink using hourly solar irradiation and temperature profiles measured in Senegal in February 2005, and a domestic load profile. Maximum power point tracking is performed with the incremental conductance algorithm, while a PI controller maintains the DC bus voltage at its 395 V reference. A rule-based energy management strategy coordinates PV generation, storage and load supply according to the instantaneous power balance and the battery state of charge (SOC). Results show that the DC bus voltage remains globally close to its reference despite fluctuations in solar irradiation, apart from a transient drop to about 260 V around 275 h. The battery SOC stays close to 50% over the whole month, indicating stable operation of the strategy under the simulated conditions. This study provides a basis for analysing the sizing and operation of PV–battery systems in the sub-Saharan African context.