We report a design method to enhance the output power of vibrational microelectromechanical system (MEMS) electrostatic energy harvesters by reducing the reactive power that does not contribute to the net output. The mechanism of enhancing the active current while reducing the reactive current is analytically studied using an equivalent circuit model of electret-based velocity-damped resonant-generator. Reduction of the internal parasitic capacitance associated to the contact pads and electrical interconnections significantly improves the power factor and increases the deliverable power. The design strategy is applied to an actual device that produces 1.3 mW from the vibrations of 0.65 G (1 G = 9.8 m s⁻²) at 158 Hz, suggesting a 2.9-fold enhancement of output power by increasing the buried oxide layer thickness from 1 m to 3 m.

我们报告了一种设计方法，通过减少对净输出没有贡献的无功功率来提高振动微机电系统 (MEMS) 静电能量收集器的输出功率。利用驻极体速度阻尼谐振发电机的等效电路模型，分析研究了提高有功电流同时降低无功电流的机理。与接触垫和电气互连相关的内部寄生电容的减少显着提高了功率因数并增加了可传送的功率。该设计策略应用于实际设备，该设备从 0.65 G（1 G = 9.8 ms ^-2) 在 158 Hz，表明通过将掩埋氧化层厚度从 1 增加到 2.9 倍，输出功率提高了 米到 3 米。