The Research on EMI of High-Speed Railway to NDB

The electromagnetic interference caused by electrified high-speed railway (HSR) through the protection areas of nondirectional beacon (NDB) is an important issue, especially when the train passes through the neutral section (NS). In this article, based on the theory of multisection transmission line and considering complex factors, the calculation method of medium-frequency current and electromagnetic emission (EME) on the contact wire (CW) when the train passes through NS is given. The radiation properties of the CW were studied quantitatively and its validity was verified by practical measurement. Then, the influence of HSR on NDB navigation signal is analyzed, and the protection distance of NS is given. This method provides theoretical basis for EME of HSR and guidance for airport site selection.