Increased pollution in the protective earth

• EMC has received increasing interest over past decade. Several standards regarding EMC have been developed. Although manufacturers design and manufacture interference-free equipment in accordance with standards, disturbances are still a problem. According to the current EMC legislation, conducted emissions are to be measured using a LISN between the utility grid and the equipment under test. However, it should be noticed that there is no correspondence between the EMC environment measured at an installation site and the EMC environment measured by the LISN. In this paper some documented cases where electrical equipment are disturbing each other are highlighted and EMC standards are discussed. In the paper it is shown that EMC related problems occurring in the examples all have the same origin: current flow in the PE. The leakage current is fed into the PE via the filters or by a capacitive coupling to the ground. The increased use of power electronic equipment might lead to the need of a complete re-build of the entire grid. An alternative solution to the problem would be to stop the leakage current from being fed into the PE.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Energiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Energy Engineering (hsv//eng)

Keyword

EMC

LISN

protective earth

leakage current

Energiteknik

Energy Engineering

Publication and Content Type

ref (subject category)

kon (subject category)