Power management strategy for hybrid vehicle using a three-port bidirectional DC-DC converter

The electric energy storage system (ESS) used for electric vehicles (EVs) or hybrid electric vehicles (HEVs) usually is a battery. The development of practical EVs and HEVs has been limited by the costs and effectiveness of ESS. Several problems with batteries include overheating, low energy storage capacity, low charging and recharging efficiencies, as well as life time. Installing a super-capacitor (SCs) as a second power source to solve some of the battery problems and to improve the performance of electric vehicles is a feasible and perfect solution. In this paper, a model of hybrid energy storage for electric vehicle with a battery, a SCs and a three port bidirectional converter was designed. To have smaller current ripple for the battery and SC which results in improved electric mode efficiency in hybrid vehicle and to achieve more control flexibility three-port bidirectional converter with novel control strategy, used for manage energy between battery and SCs. The results show that the proposed hybrid energy storage system, improves the working conditions of the battery, furthermore the peak and average current of the battery is reduced due to the working of the SCs, which provided better working conditions for the battery and increased the operating life of the battery. For this purpose, simulations were made in MATLAM/SIMULINK environment.