Tunneling Magnetoresistance Current Sensors for Power and Energy Systems: A Critical Review of Architectures, Error Mechanisms, and Design Trade-Offs

Current measurement in Power and Energy Systems must accommodate direct-current components, converter harmonics, fast transients, wide dynamic ranges, and strong electromagnetic interference. Tunneling magnetoresistance (TMR) sensors offer high field sensitivity, broad intrinsic bandwidth, compact size, and low power consumption, but these device-level advantages do not directly translate into system-level accuracy or usable bandwidth. The principal contribution of this review is a unified framework organized around sensor architecture that connects magnetic tunnel junction transfer characteristics and Wheatstone-bridge behavior to complete current-sensing systems. Unlike previous reviews organized mainly by materials, operating principles, or applications, this work compares surface-mounted, linear-array, ring-array, and magnetic-core open- or closed-loop architectures across sensor-element, circuit, external-field, manufacturing, and installation errors, together with compensation strategies, test conditions, implementation burden, and application evidence. It further distinguishes device metrics from complete-system performance and laboratory feasibility from deployment evidence. The comparative analysis identifies current-to-field geometry, bridge matching, thermal drift, external interference, signal conditioning, and feedback dynamics as the coupled factors that determine usable range, accuracy, and bandwidth. Their relative importance changes with architecture: surface-mounted layouts are especially sensitive to placement and crosstalk; linear and ring arrays introduce channel-matching and spatial-calibration requirements; and magnetic-core designs are additionally constrained by core behavior and, in closed-loop systems, feedback dynamics. These relationships provide a requirements-driven basis for selecting an architecture according to waveform, current range, installation geometry, interference environment, and uncertainty requirements. Meaningful comparison further requires common-condition evaluation of amplitude and phase error, overload recovery, environmental stability, and calibration transfer across devices and installations.