| As technology advances, there is a strong trend towards integration and miniaturization of individual systems to enhance reliability, size, and cost. Although there is a wide assortment of technologies available today for making current measurements for power electronics applications, most of these are confronted with severe obstacles when being considered for high-scale integration. Integrated solutions often incur severe tradeoffs between important qualities such as galvanic isolation, bandwidth, accuracy, size, and cost.; This thesis presents concepts and methodologies for designing integrated current sensors for power electronic modules and bus structures using Giant Magnetoresistive (GMR) point-field detectors. Although the GMR field detector offers galvanic isolation, small size, high bandwidth and accuracy, achieving a current sensor design that fully utilizes all of these attributes is non-trivial. Avoiding the use of a magnetic core in the design takes advantage of the high field sensitivity of the GMR, but requires extra attention to field issues that other technologies do not encounter. Concepts for decoupling cross-coupled magnetic fields are introduced and experimentally demonstrated. A method for evaluating the dynamic behavior of fields due to the skin effect and the proximity effect is introduced for the purpose of optimizing the use of the detector's bandwidth and range-to-resolution ratio.; Using the GMR field detector as an integrated current sensor subjects it not only to cross-coupled magnetic fields, but a wide variation of temperatures as well. Therefore, it is also shown that it is possible to use the temperature sensitivity of both the GMR field detector, as well as the required biasing magnets to serve as independent temperature sensors. These multiple temperature signals can be used to compliment an active thermal control strategy for enhancing reliability and performance of power electronic systems. |
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