## 4 Evaluation  
Based on the presented concept, a 24 m full-scale Demonstrator was constructed in the south of Munich between late 2022 and mid-2023. Alongside the levitation and propulsion systems, vacuum and safety were also tested. After TUV Sud safety approval was obtained, it was tested with passengers in vacuum [2]. A front view of the Demonstrator from within the tube, showing the guideway and the shell of the passenger module, is depicted in Figure 6.  
Figure 5: Schematic of the derived TUM Hyperloop Concept proposal. Electrically powered components are colored dark blue. Passive components are light blue or gray. Compared to the presented concept, the Demonstrator does have three major simplifications. Firstly, the electromagnetic suspension was powered by a DC power supply by means of a cable chain, instead of an onboard battery. This simplified the certification and testing of the prototype. Secondly, a permanent magnet array, instead of the superconducting excitation, was featured in the pod, to speed up the development process. The superconducting excitation will be tested on a separate test wagon in the Demonstrator tube. Thirdly, the auxiliary suspension system for lane switching was not implemented at that point. The following will provide an evaluation of the presented suspension and propulsion systems, assessing the experiences had on a conceptual level during testing. The electromagnetic suspension generally worked as expected. Nevertheless, there were several challenges to overcome, and control software is still being improved to reduce vibrations in the pod. A major challenge that was underestimated when switching from the 1D test stand to the full-scale Demonstrator was the dampening system between the passenger module and the service module. This load change is modeled in the controller as disturbance, increasing the performance requirements of the controller significantly. Another point that was and is of great scientific importance is the interactions between the systems that are hard to model. The propulsion, levitation and guidance systems interact magnetically, electrically and in software. Plotting the airgap deviation shows that switching on either propulsion or guidance during levitation leads to extra disturbances. In the current state, the controller is capable of handling those extra disturbances, but vibrations are induced that, in some cases, are also noticeable for the passengers. The self-developed electronic system powering the levitation coils worked seamlessly, until, in winter, an operating temperature of less than 5 \({}^{\circ}\)C was reached. This triggered over current protection, probably caused by a change of behavior of the silicon carbide MOSFETs. Several current-limiting measures in the software and hardware fixed this problem. The emergency skids proved to be helpful for maintenance, testing and certification. They ensured safe suspension and defined braking, even at a complete loss or disconnection of power. One advantage that became clear only during construction was the separation of the guideway and the tube. It allowed for separate accuracies in both the elements and the independent production of the tube and guideway. Additionally, in a concrete tube, the anchoring of parts is challenging. The guideway allowed for a screw-through connection of the levitation and guidance rail, promising a  
Figure 6: Photo of the front view of the TUM Hyperloop Demonstrator. stable connection over a long lifetime and, therefore, improved performance compared to a ceiling-mount. The construction of the propulsion system showed that the air-cored armature might actually not be much more expensive than a laminated steel reaction rail for a short stator reluctance motor plus an inductive power transfer system. However, the conceptually determined clearance between the levitation reaction rail and the propulsion armature results in a substantial propulsion air gap, necessitating a powerful magnetic excitation.