Global Fast Nonsingular Terminal Sliding Mode Control With Finite-Time Extended State Observer for Levitation Systems of High-Speed Maglev Train

High-speed maglev trains are attracting attention for their contactless operation and enhanced comfort. However, high-speed operation makes these systems particularly susceptible to significant disturbances that can impair levitation control performance. To address this challenge, this study proposes an advanced control strategy that integrates a global fast non-singular terminal sliding mode control (GFNTSMC) with a finite-time extended state observer (FTESO). Based on the nonlinear dynamic characteristic, the proposed FTESO enables real-time disturbance estimation while the GFNTSMC provides effective compensation. Theoretical validation of finite-time stability is proven using Lyapunov stability theory. Numerical simulations and hardware-in-the-loop (HiL) experiments consistently show that the proposed FTESO-GFNTSMC method significantly outperforms the conventional linear extended state observer-based non-singular terminal sliding mode control (LESO-NTSMC), achieving a 94.1% faster convergence rate and a 99.3% reduction in maximum tracking error under equivalent disturbance conditions. This demonstrates its effectiveness as a high-performance control strategy for maglev train operations.