Ultracapacitors modeling improvement using an experimental characterization based on step and frequency responses

This paper deals with ultracapacitors modeling that has been improved for high power source purpose such as in hybrid and electric vehicles applications. An experimental method based on the combination of step and frequency response has been implemented and used in a dedicated test bench. First, a critical overview of available ultracapacitors models is made and a new approach is proposed. Then, after constant current and impedance spectroscopy tests, the experimental results are presented and discussed. Finally, the exploitation of the tests results leads to the identification of a proposed model parameters. This electric circuit is validated by comparing simulation to experimental curves.