Optimal Power Sharing Control of the Hybrid Energy Storage System of an Electric Vehicle Along a Standard Driving Cycle

The paper presents a strategy of energy loss minimization within a hybrid energy storage system of an electrical vehicle, composed by a battery and a supercapacitor. The optimization of the power sharing between these energy storage devices is performed for the New European Driving Cycle, using the Particle Swarm Optimization algorithm. The minimum energy storage required to pass through the driving cycle is taken into account as a time-variable constraint during the optimization. The dimension of the search space increases with the dimension of the optimization vector, which has to be kept low in order to keep the complexity of the problem manageable. It is shown, that the subdivision, and piecewise optimization of the driving cycle improves the result by means of relaxation of the constraint represented by minimum level of the required energy storage.