Measured and Computed Effect of Holes on Low-Frequency Magnetic Shielding Performance of Electrical Steel Sheet

Electrical steel sheet is widely used in constructing chambers and enclosures for magnetic shielding typically at power frequencies. In practice, sheets are cut into various shapes and drilled prior to forming or joining. The shielding performance can be affected by these processes. This paper presents the effect of a drilled hole on shielding performance of electrical steel sheet at 50 Hz. Both measurements and modeling show that the degradation is very localized around the drilled hole and it will not compromise shielding performance of the whole shielding enclosure