Research on Caputo Fractional Calculus Sliding Mode Control for Attitude Detection System of Wireless Transmission Spherical Motor

This article presents a Caputo-type fractional calculus sliding mode control method for attitude detection in spherical motor wireless power transfer (WPT) systems. It introduces a rapid rotor attitude estimation method using inductance estimation, avoiding complex finite element analysis (FEA), and integrates this with magnetic field analysis to ensure accurate detection. Additionally, a Caputo-type fractional calculus sliding mode control method is proposed for the trajectory tracking problem of the spherical motor motion system, combining fractional calculus with sliding mode control by constructing fractional sliding surfaces and fractional reaching laws, with the stability of the method proven by the Lyapunov theorem. Subsequently, the method is compared with traditional sliding mode control simulations, demonstrating a significant reduction in input signal oscillation and improved trajectory tracking performance of the spherical motor. A comparison of WPT attitude detection methods with visually improved fast discriminative scale space tracking (IFDSST) algorithm and microelectromechanical system (MEMS) fusion algorithms highlights the system’s real-time capabilities. The results indicate that the angular error of the WPT attitude detection method is consistently below 2%. Finally, the effectiveness of this method was validated through closed-loop control experiments, providing experimental evidence for its performance.