Design and implementation of an energy metering environment protection system

Abstract

This dissertation describes the research study done to design and implement an energy metering environment protection system applicable to three-phase metering systems. The metering environment is the energy meter, its enclosure, and the cables that bring and take out power from this energy meter. Over the past years, Umeme Limited has tried to reduce energy losses from 26.1% recorded in 2012 to 18% in 2021 but this is still high, and the problem of high energy losses still exists to date, a big percentage of these losses being commercial losses. Taking an example of year 2021, Umeme planned to have reduced the losses to 14% from the 17.5% in June 2021 but in June 2022, the losses instead had increased to 18% instead of reducing. Electricity is stolen in different approaches within and outside the energy meter including direct hooking from the utility powerline. Umeme has tried to reduce electricity theft by installing automated meter readers, smart meters, and aerial bundled conductors but gaps in these solutions still exist. High energy losses affect the final electricity tariff rate that the end user pays for using electricity. One of the major gaps that exists in the existing solutions is the inability to capture some bypasses and tampered/ faulty energy meters. This thesis describes an anti-theft device that was researched about and developed based on the different electricity theft approaches often used to steal electricity. It would be installed between the energy meter and customer circuit breaker to monitor consumption and detect electricity theft with logic of behavior of three-phase systems instantaneous values under normal and bypassed conditions introduced by an external circuit. Also, three-phase star configured circuits neutral currents differ when a system is by-passed from the normal metered circuit. This thesis further describes the functionality tests that were done on this developed device through simulations in NI multisim and field tests. A prototype was developed and installed in the field environment to test its functionality. A cost benefit analysis showed a positive net present value and a two-year payback period which indicated that the project would be a viable one to take up.