Impact-based electrostatic harvesters considered as a multi-source problem

This paper presents a simulation study that compares two microscale impact-based electrostatic energy harvesters with multiple transducers contributing to power conversion as separate electrical sources. One harvester with rigid end-stops has two-sources and another with transducing end-stops has four sources. Each source is connected to a voltage-doubling rectifying circuit and the outputs of all rectifiers charge a common storage capacitor thus constituting a parallel passive circuit topology. The two devices are constrained to have the same total chip area and maximum displacement limit d_max=10μm. Generator performance is evaluated by considering the voltage reached on a storage capacitor C=100nF within 5s. Simulation results show that the impact device with the four-source scheme yields an output energy of 50.0nJ in the impact regime, while the reference device exhibits a saturated energy of 24.5nJ.