Sähkövirranmuuntaja keski- ja suurjännitelaitosta varten

摘要

The current transformer (8) intended for a medium- or high-voltage system exhibits a current sensor (9) and an annular support body (13) used for holding the current sensor (9). The current sensor (9) held by the support body (13) is constructed as toroidally wound coil (14) and, after installation in the system, concentrically surrounds a current conductor (5) of the system. This current transformer is intended to have small dimensions and to be distinguished by a current sensor (9) which can be installed without problems at any point in the system. This is achieved by the fact that the coil (14) is wound in a manner of a Rogowski coil onto an annular core (23) of non-ferromagnetic material of essentially rectangular cross section cut in the axial direction with a small radial dimension in comparison with the radius of the core (23) and with its axial extent, and is arranged in a hollow space (13) of hollow cylindrical construction in the support body (13) which is shielded against electrical fields.