Loop parameters on dynamic characteristics of digital closed-loop accelerometer

The bandwidth of the digital closed-loop quartz-flex accelerometer was only 10 Hz under the integral controller. The servo loop parameters were adjusted to improve the system dynamic performance, and a proportional integral controller was designed to ensure that the system was no difference. The system mathematical model was established. With the method of implicit function, the influences of the loop parameters (including sampling coefficient, proportional coefficient and integral coefficient) on the closed-loop bandwidth, stability and static accuracy were analyzed. To build the system prototype, experimental results of the bandwidth and zero bias stability show that the system bandwidth is positively correlated with the loop parameters, among which proportional coefficient is the most significant factor on the dynamic characteristics of the system. Test results are in consistence with the theoretical analysis, which provides the theoretical basis and experimental instruction for dynamic characteristics adjustment of the digital closed-loop accelerometer.