A comparative study and parameterization of supercapacitor electrical models applied to hybrid electric vehicles

Supercapacitors, also referred as ultracapacitors, are very attractive elements to combine with batteries or fuel cells in hybrid electric vehicle applications. This is due to the fact that they present some interesting features like high power density, long life cycle and low maintenance. Accurate supercapacitors circuit models are very important because they allow optimizing the sizing and power management of the powertrain. These models must be able to emulate the static and dynamic response with accuracy and robustness, avoiding excessive complexity. In this paper, three models of supercapacitors widely used in the literature have been selected. In order to estimate the different parameters of the equivalent circuit, an iterative method is implemented in Simscape-MATLAB®. The optimization function fits the simulation data with the experimental data. After that, the supercapacitor models are validated applying the European driving profile ECE15. Finally, a summary of the recommended supercapacitor model for automotive applications is shown, as well as the main conclusions reached along the analysis.