关键词: 静电力, 加速度计, 阻尼补偿, 闭环控制

Abstract: Based on an electrostatic forcebalance quartz acceleraometer, the dynamic model is established and a closeloop control system based on electrostatic force is designed. The stiffness model and deflection model of the pendulous reed are established, indicating that the nonuniform of the capacitor gap variable quantity affects the drive and sense parameters. Besides, the electrostatic force model of drive capacitor is established, and the effect of negative stiffness on the dynamic model is analyzed. To decrease the mechanical thermal noise, the accelerometer is evacuated, which causes the system damping decreasing to zero. To avoid oscillation near the system resonant frequency, a damping compesator is added into the closeloop system. Besides, an integal element and a correction element are designed to increase the rapidity and atablility of the whole system. The simulation results show that, the bandwidth is 2 380 Hz, and the overshoot abd response time are 3% and 0.5 ms respectively. Besides, the closeloop system can work stably with the increasing of negative stiffness.