Permanent Magnet Guideway Irregularity Measurement and Characterization by Single Dewar HTS Pinning Maglev System

High-temperature superconducting (HTS) pinning maglev has attracted attention due to its advantages of stable levitation without external energy, and integration of levitation and guidance. As one of the main excitation sources of the HTS pinning maglev system, permanent magnet guideway (PMG) irregularity is affected by the geometric and magnetism of PMG together. Therefore, the measurement method only for geometry in wheel-rail systems no longer meets the measurement requirements of PMG irregularity. In addition, the current research on HTS pinning maglev trains is mainly based on the test line, which has certain requirements for repeated measurement and measurement convenience. In this article, various sensors are set on a single Dewar HTS pinning maglev system. PMG magnetic induction intensity signal, the vibration response signal, and the geometric signal are measured, respectively. The equidistant track marker on the PMG surface is used as a keyphasor pulse signal to realize the spatial resample method. After converting the time-domain signal to the spatial domain, the PMG local irregularity evaluation is carried out. Based on the seven-parameter fitting model, the PMG irregularity spectrum is fit. Taking the Chinese mainline railway track spectrum as the contrast, it can be concluded that the mid-wave irregularity of the HTS pinning maglev system is higher. The research content of this article provides a theoretical basis for the selection of measurement methods under different measurement requirements and conditions. The obtained irregularity power spectrum can provide a reference for the dynamic simulation of HTS pinning maglev.