Modeling and model validation of supercapacitors for real-time simulations

Supercapacitors are becoming very important in the automotive and energy and power industry due to their specially characteristics, in particular in the field of hybrid vehicles and hybrid energy storage systems. For this reason, having accurate models that can represent the behavior of such systems is necessary and the main important characteristics of supercapacitor are a high-power density and a long lifetime with low maintenance. This thesis focuses on modeling supercapacitors to the study of their behavior in a short time period. As, their operation often short intense power deliveries. The goal of this thesis is to compare the accuracy of equivalent-circuit models of supercapacitors together with their required execution time for real-time simulations. In the first chapter, the operation of the supercapacitor from the molecular point of view and the principal of storing energy in a supercapacitor is introduced. Common operation modes of supercapacitors are also introduced. Next, equivalent-circuit models of supercapacitors are introduced. The models are implemented in MATLAB/Simulink and their responses are compared with the experimental results. The parameter estimation results. The parameter estimation tool of MATLAB has been used to estimate the model parameters for each model. At the end, the models are compared in terms of inaccurately reproducing the experimental response of a supercapacitor. Lastly, the models are compared in terms of their required execution time for real-time simulations. The models are implemented in RT-LAB software and simulated on the Opal-RT’s OP4510 real-time simulator. Here the execution times of the models compared with the goal of representing a large number of supercapacitor cells.