Fast Phase Error Identification of MEMS Gyroscope Based on Sinusoidal Quadrature Disturbance and FFRLS Algorithm

This paper proposed a fast phase error identification method for MEMS gyroscopes to reduce zero rate output (ZRO) drift. The method applies a sinusoidal disturbance signal to the quadrature suppression electrode of the MEMS gyroscope. The phase error is identified using a designed forgetting factor recursive least squares (FFRLS) algorithm based on the outputs of the quadrature suppression loop (QSL) and the force rebalanced (FRB) loop. Compared with previously methods, this approach enables real-time phase error identification during gyroscope operation. The identified phase error can be directly used for ZRO compensation. The identification accuracy and effectiveness of the method were analyzed through simulations. Experimental results indicate that the identified phase error is -14.1026 deg. After compensation, the gyroscope's bias instability was reduced by a factor of 3.5, reaching 0.0965 º/h.