Energy management technique of hybrid energy storage system-based DC microgrid

Abstract

The generation of variable energy from photovoltaic (PV) is significantly affected by unpredictable fluctuations due to weather changes. Additionally, the variability in load demand is a critical consideration for microgrid. Consequently, the implementation of an energy storage system is essential to address these challenges. This study presents a novel energy management technique (EMT) for hybrid energy storage systems (HESS). The innovative approach incorporates a low-pass filter (LPF) to optimize power distribution between batteries and supercapacitors (SC), thereby enhancing system stability and prolonging battery life. The proposed LPF-based EMT facilitates optimal power allocation, improves system stability by effectively filtering high-frequency power fluctuations, and extends battery life through reduced stress and optimized charge-discharge cycles. It developed a comprehensive system model to enable accurate simulation and analysis, supported by rigorous experimental validation that demonstrates the effectiveness of our method. This approach successfully redirects high-frequency power demands to the SC, stabilizing the DC link voltage. Comprehensive simulations indicate the system's capability, revealing quantitative improvements in battery performance and efficiency across various LPF time constants τ, representing a significant advancement in renewable energy control. The simulation results confirm that the proposed architecture and system representation achieve optimal DC link voltage stability. Furthermore, increasing the τ reduces the state of charge (SOC) of the battery, contributing to an overall increase in battery lifespan.