Supercapacitor charge redistribution analysis for power management of wireless sensor networks

To support many power management applications in wireless sensor networks, a previously developed model is modified to predict the terminal behaviour of a supercapacitor under a dynamic charging/discharging power profile. In addition, a robust model parameter identification method based on the genetic algorithm is developed to determine the model parameters using a dynamic test and a self-discharge experiment. On the basis of the supercapacitor power input model, charge redistribution related figures of merit are derived and used to evaluate the significance of charge redistribution for supercapacitors with various rated capacitance. The results show that supercapacitors with different sizes share similar charge redistribution phenomenon. Furthermore, the charge redistribution significance is studied from several perspectives to provide guidelines for designing power management techniques that can achieve full potential of the energy stored in the supercapacitors.