Using the Dynamic Behavior of Superimposed Fields for Point-Field-Based Current Sensing

The dynamic behavior of magnetic fields surrounding adjacent current-carrying conductors is investigated for the purpose of point-field-based current sensing. The influence of eddy currents on magnetic field distribution over the useful spectrum (dc to 1 MHz) is quantified by using a spatially dependent metric, the 5% flat bandwidth (FBW). A comparison of field distributions at DC and 1 MHz shows the origin of the FBW function, which is unique to each conductor's cross section and nearby environment. The FBW fields for several different conductor geometries are analyzed. Superposition is used for conductor geometries that have multiple currents. A method for determining optimal field detector placement using optimization functions is introduced.