Integrated current sensing for power electronic modules using GMR field detectors

The latest developments in point field detection for integrated current sensing are discussed. The effects that the skin-effect has on bandwidth and accuracy are explored. Numerical calculations and experimental measurements are performed on conductors with rectangular cross-sections. Point field measurements are made using giant magnetoresistive (GMR) field detectors, and are compared with results from numerical analyses. Two-dimensional finite element models demonstrate the tradeoff between flat measurement bandwidth and field strength as a function of frequency. Optimization functions are used to determine the best placement of the field detector for use as a current sensor.