Optimization of electrostatic energy harvesting device for wireless sensors application

In this paper, we put forward a coupled electromechanical model with differential equation arrays for an electret-based energy harvester with out-of-the plane gap closing scheme. The model is numerically solved for output voltage and displacement of the moveable electrode with given parameters by Matlab/Simulink software. Furthermore, system optimization is carried out using the coupled model to find the optimal values for the load resistance and the initial air gap to maximize the output power. For instance, at an external load resistance of 1 GΩ, a power output of 67 μW is achieved with the initial gap of 380 μm. This output power is promising for the potential applications on the wireless sensor networks and the internet of things.