Characterization, Analysis and Modeling of an Ultracapacitor

Ultracapacitors are potentially promising power-augmentation devices in hybrid powertrains. A commercial ultracapacitor module was characterized under standard procedures to assess its performance. Tests were carried out on a platform, with which ambient temperature can be regulated and charge/discharge procedures can be implemented. Key parameters of the ultracapacitor module obtained from tests were used to develop a control-oriented ultracapacitor model proposed in the paper. Simulation results of this model in a stable discharge procedure and in dynamic procedures (i.e. driving cycles) showed excellent agreement with results obtained from experiments, indicating that the ultracapacitor model is accurate enough to be used in further electric powertrain control simulation.