Influence of Velocity Feedback Time Delay on the Nonlinear Dynamic Characteristics of Maglev Trains Under Unsteady Aerodynamic Forces

ABSTRACT Time delays frequently arise in active control systems due to sensor sampling, signal transmission, and actuator response, making their effects on system dynamics non‐negligible. This paper investigates how velocity feedback time delay influences the nonlinear dynamic characteristics of a maglev train subjected to unsteady aerodynamic forces. First, a time‐delay dynamic model of the maglev system under unsteady aerodynamic forces is developed. Then, using the method of multiple scales (MMS), the frequency response equations for the maglev train are derived, and the steady‐state solutions are evaluated for a stability assessment. Finally, the influence mechanism of time delay on the system's nonlinear vibration is explored under various parameters, such as unsteady aerodynamic force, train mass, displacement, and velocity feedback gain coefficients, with a particular focus on mitigating adverse effects stemming from the time delay. The results reveal that time delay plays a pivotal role in determining the vibration amplitude and overall system stability and that its influence exhibits periodic characteristics. In practical applications, judiciously tuning the time delay can help avoid its adverse impact. This study offers theoretical insights into the severe vibrations observed in real maglev operations and offers guidance for designing and optimizing control strategies to enhance ride comfort and system reliability.