Overload protection for AC-DC transfer measurement standards

Abstract: Electrical transient overloads (ETOs) are inherent to electrical and electronic systems, especially those that are composed of semiconductor materials. However, as the subject has received research attention since the mid-1900s, design engineers are familiar with this class of electrical or electronic disturbance. Thus, in most electrical and electronic applications, ETOs are compensated for through the implementation of an ETO protection device(s). Nevertheless, more work is still to be done to develop efficient techniques to mitigate this class of disturbance. The work presented in this dissertation identifies the most probable sources of ETOs in the alternating current-direct current (AC-DC) transfer measurement system. The AC-DC transfer measurement system is used to provide electrical calibration services to the national industry and national and regional standardisation bodies, thus complementing the metrological traceability of the international (SI) units of AC current, voltage and power. Thermal converters (TCs), which serve as the main elements of the AC-DC transfer measurement system, are most susceptible to damage and destruction from ETO events, which may arise during the measurement process or be caused by human error. This work also presents a conceptual ETO protection solution for thermal converters, developed through mathematical and simulation analysis...M.Phil. (Electrical and Electronic Engineering