Circuit Approach Solution for Magnetic Shielding by Cylindrical Shells Against a Unidirectional Current Source
XU Lin1, FU Zheng-cai1, SONG Chun-yan2(1. School of Electronic, Information and Electrical Eng., Shanghai Jiaotong Univ.,Shanghai 200030, China;2. Hangzhou Municipal Electric Power Bureau, Hangzhou 310009)
Metallic cylindrical shell with external loop can effectively shield the magnetic field excited by a unidirectional current. The shielding effectiveness is usually evaluated by numerical method, which is not convenient for application.A circuit approach was employed to derive the shielding effectiveness of the metallic shell with external loop. Close-form expressions of the circuit parameters and easy-to-use formula for the calculation of shielding effectiveness were given. The effectiveness of the derived formula was validated by 2-D boundary element method simulation and laboratory measurements. Application example was also given.
【CateGory Index】： TM15