Effects of Using Ultracapacitors on Acceleration and Regenerative Braking Performances in Hybrid Electric Vehicles

The concept of Energy Storage System (ESS) in Hybrid Electric Vehicle (HEV) is the most important challenging part of HEV design. Batteries are the main electric ESS which has mostly used for supplying the energy requests; researches confirm this fact that applying a secondary ESS can be so helpful for the overall system performance. Ultracapacitors based on their specifications are the first candidate for this role, Very high power delivery and fast charging are the most famous parameters of ultracapacitors which make them suitable for HEVs. Each driving cycle has many acceleration and braking times which leads to have fast dynamic reactions in energy storage systems. In this paper the role of ultracapacitor as a secondary ESS for improving the system performance in acceleration and regenerative braking times has been inspected and the results show remarkable advantages for the proposed hybrid system configuration and energy sharing strategy.