Mutual Inductance of a Precise Rogowski Coil in Dependence of the Position of Primary Conductor

The Rogowski coil is a well-known current-to-voltage transducer. To use it for the high-accuracy measurement of ac current (at power supply frequency), all influencing quantities and their contribution should be recognized and analyzed. Thus, the partial influence due to the deviation from the central position of the primary conductor for a real sensor, with the nonhomogeneous density of secondary turns, is given in this paper. The measured deviation of mutual inductance in this case showed very good agreement with the theoretical prediction, which is promising for the expected application of such a sensor.