IEC 61869 compliant Rogowski coil for volume production

International instrument transformer standardization efforts include alternative designs in their scope. Rogowski coils fall within the so-called “low power passive current transformers” category. The main disadvantage of easy-to-use split-core Rogowski coils can be overcome by adding a simple ferrite core at the clasp: short-circuiting the magnetic path by a soft magnetic part in the region where the winding density cannot be kept constant leads to a near perfect independence of the ratio error on the position of the primary conductor. A well-characterized winding support ensures an absolute error low enough to be acceptable for billing purposes.