Abstract: In response to the frequency tuning requirements of superconducting cavities in superconducting linear accelerators, the Institute of Modern Physics of the Chinese Academy of Sciences has designed and developed a helium pressure tuning controller. By real-time monitoring of helium pressure and motor position, the fast pulse solenoid valve is precisely controlled to achieve frequency stability of the superconducting cavity. The study focuses on the nonlinearity and delay issues of helium pressure regulation. Traditional control methods are difficult to meet the requirements of high precision and fast response of superconducting cavity tuners. Therefore, an optimization scheme is proposed: using an adaptive algorithm to dynamically adjust control parameters to cope with nonlinear characteristics, combined with Smith predictive control to compensate for system delays to improve response speed. Experiments show that this scheme significantly improves the closed-loop control accuracy, robustness and dynamic performance of superconducting cavity frequency tuning, meets the strict requirements of superconducting cavity frequency synchronization in superconducting linear accelerators, and provides an efficient solution for superconducting cavity tuning.