Reduction of the effect of the overflow reset in resonant frequency servo loop for resonator fiber optic gyro

Abstract

Digital proportional-integral (PI) controller is always adopted in the resonant frequency servo loop in a highperformance resonator fiber optic gyro (R-FOG). Large reset pulse at the output of the R-FOG occurs on the overflow reset of the digital PI controller, which limits the lock-in frequency accuracy and system response. To reduce the effect of the overflow reset in the digital PI, an auto-controlled reset technique is proposed and experimentally demonstrated. As a result, the time back to the lock-in state falls from 8 s to 5 ms. With the integration time of 1 s, the equivalent accuracy of the resonant frequency servo loop is improved to 0.18 deg/h.