An Effective Nuclear Magnetic Resonance Gyroscope Control Method Based on ESOPI-PLL

In the design of nuclear magnetic resonance gyroscopes, the closed-loop control of the excitation magnetic field is crucial. Among various control methods, the phase-locked loop (PLL) is widely used to enhance the dynamic characteristics and stability of the gyroscope. This research employs the Second-Order Generalized Integrator (SOGI) as the phase detector, with the loop filter utilizing PI control. However, the system, being of type 2, cannot track acceleration signals without a static error. To address this limitation, we propose a loop filter design based on an Extended State Observer (ESO) integrated with PI control, effectively transforming the system into ESOPI-PLL, which is a type of Type3-PLL. Compared to the traditional SOGI-PLL system, simulation results demonstrate that our proposed scheme extends the gyroscope range to 2000 °/s, with a bandwidth of 30Hz, and achieves zero static error tracking. This advancement presents significant application potential for nuclear magnetic resonance gyroscopes.