Electric control systems, signal detection equipment, and power conversion modules for high-speed trains and rail transit have the highest industry standards for the safety, stability, and anti-interference of magnetic core products. During the operation of rail transit equipment, the electromagnetic environment is complex, vibration is frequent, and voltage fluctuations are large. Ordinary magnetic cores are prone to performance drift, signal interference, parameter instability, and other problems. High precision nanocrystalline and amorphous magnetic cores, with their advantages of high magnetic permeability, strong anti-interference, and stable performance, can accurately adapt to scenarios such as current detection, signal filtering, and power conversion in rail transit, ensuring precise, safe, and stable operation of rail equipment. The rail transit project has extremely strict requirements for supply chain access, only recognizing source manufacturers with mature processes, strong batch stability, complete qualifications, and long-term supply. High reliability magnetic cores are an important guarantee for the safe operation of rail transit.