SIMULATION OF PHOTOVOLTAIC SYSTEM WITH BATTERY STORAGE FOR SUPPLY OF AUXILIARY SERVICES IN HIGH VOLTAGE SUBSTATION

Resumo

The integration of photovoltaic systems (PV) with battery energy storage systems (BESS) has emerged as an effective strategy to enhance reliability, autonomy, and flexibility in supplying critical loads. This paper presents the development and implementation, in Python language, of a computational model for simulating PV systems integrated with BESS, aimed at supplying auxiliary services in high-voltage transmission substations. The model enables hourly resolution of energy flows between photovoltaic generation, load, and battery, incorporating variables such as state of charge (SoC), depth of discharge (DoD), and battery state of health (SoH). The methodology involves comparing load and generation curves, followed by deriving the net energy balance curve for the system. Based on this balance, the model was coded using PyBaMM (Python Battery Mathematical Modelling), an open-source computational platform for battery simulation written in Python. PyBaMM is employed to simulate charge and discharge current profiles required to meet demand and charge the battery bank, considering BESS operational constraints. The model is applied to a case study with two months of simulated operation, allowing assessment of the system’s dynamic behavior and validation of the implemented control logic. Results demonstrate the feasibility of the proposed approach and highlight its potential to support sizing and performance analysis of hybrid systems in real-world applications.