Speaker
Description
Magnetically levitated (Maglev) vehicles aim to address the growing demand for efficient and sustainable high-speed transportation solutions. They offer a promising alternative to traditional modes of transportation like air travel or wheel-on-rail systems. Based on the principle of the electromagnetic suspension (EMS), these vehicles need to be actively controlled to maintain stable levitation. Current efforts focus on developing Maglev trains capable of operating at speeds up to 600km/h. At these high speeds, vertical vibrations caused by track irregularities and other disturbances pose challenges to ride safety and passenger comfort, which have to be addressed by the controller. This work proposes the application of Nonlinear Model Predictive Control (NMPC) for reducing vertical vibrations of the vehicle's car body, thereby increasing passenger comfort while ensuring stable levitation. The novel aspect of this approach is the integration of mechanical suspension dynamics into the prediction model, allowing the controller to predict and minimize the car body's vertical movement. NMPC has emerged as a promising solution for the control of high-speed Maglev vehicles due to its ability to effectively handle system nonlinearities and constraints. A dynamic model is utilized to capture the interaction between the levitation magnets and the car body by incorporating an electromagnetic and mechanical model. While the nonlinear magnet model describes the electromagnetic behavior, the two-mass model represents the suspension dynamics. The track irregularities are interpreted as unknown disturbances. The NMPC algorithm predicts the system behavior over a finite horizon and computes an optimal control input by minimizing a cost function while respecting dynamic and input constraints. The cost function is designed such that closed-loop stability and minimal vibrations are ensured. Simulations using a detailed multibody model based on the Transrapid 09 show that this approach significantly reduces vertical vibrations compared to existing methods while ensuring stable levitation.
