Modeling, Simulation, and Characterization of a Supercapacitor in Automotive Applications

In the energy storage field, supercapacitors (SCs) are gaining more and more attention thanks to features, such as high-power density, high life cycles, and lack of maintenance. In this article, an improved SC three-branch model, which considers the residual charge phenomenon, is presented. The procedure to estimate the model parameters and the related experimental setup are presented. The parameter estimation procedure is repeated for several SCs of the same type. The average parameters are, then, obtained and used as initial guesses for a recursive least squares optimization algorithm to increase the accuracy of the model. The model of a single SC is, then, extended to SC banks, testing different configurations and operating conditions. The simulation results, obtained in the MATLAB/Simulink environment for both the single SC and the different SC bank configurations, are validated with experimental tests to assess the model accuracy.