Enhanced Energy Management Algorithm for Battery/Ultracapacitor-Based Hybrid Energy Storage System Using Interleaved DC-DC Converter

In many of the hybrid energy storage systems (HESSs), the effective utilization of ultracapacitor (UC) and controlling the energy exchange between the battery and UC within safe operational boundaries is crucial for enhancing system efficiency and overall performance. In general, the conventional energy management algorithm (EMA) is commonly employed to regulate the power sharing in a battery/UC-based HESS. In addition, a control loop for UC is integrated to ensure the maintenance of the UC voltage at its nominal value during load variations. However, this results in limited utilization of UC energy, as the UC voltage varies with a narrowband. The system performance can be improved by effective utilization of the UC. So, in this article, an enhanced EMA by utilizing the UC voltage band with UC voltage control loop is developed to increase its power delivery capacity of UC and control the battery/UC current. In addition, an interleaved boost converter (IBC) is used in an active configuration in place of a conventional boost converter (CBC) to improve the efficiency and health of the battery by minimizing the input ripple current. Various operational modes have been deliberated based on the voltage band of the UC to enhance functionality and maximize the utilization of the battery/UC-based HESS.