A control algorithm to reduce electric vehicle battery pack RMS currents enabling a minimally sized supercapacitor pack

This paper presents a novel control algorithm that dynamically directs the current between a small supercapacitor / ultracapacitor pack and an electric vehicle battery to create an economical hybrid energy storage system. This has the potential to extend the service life of the battery by reducing the battery peak currents, adding value to the electric vehicle. To validate the effectiveness of the small SC pack on the battery's RMS and peak currents, simulations are presented using Powersim with drive cycle data from the Advanced Vehicle Simulator MATLAB application. The proposed algorithm demonstrates a 19 percent reduction in the battery pack RMS current while using an SC pack that has up to six times less total capacitance than existing SC-based hybrid energy storage systems.