Design of a Self Regulated and Protected Electrification Transformer

[摘要] Electrification of rural areas is one of the biggest challenges faced by ESKOM andmethods are required to extend medium voltage distribution lines to these oftenremote areas. As loads increase due to line-extension, in-fills and energy theft,maintenance cost and life expectancy of distribution and power transformersbecomes more critical. The thesis addresses these two aspects with thedevelopment of a self regulated and protected electrification transformer thatmakes use of current, voltage and ambient temperature measurements toregulate voltage and protect hardware from overloading. The design of thehardware that allows the system to run at 200% load without decreasing thelifetime of the transformer is examined. Temperature estimation techniques areused to estimate the temperatures in the 16 kVA, 22 kV to 230 V, distributiontransformer to run above nameplate ratings without causing damage. The controlof the system is implemented on TMS320F2812 digital signal processor from TIthat is DSP/BIOS compatible. The control software is implemented usingDSP/BIOS, which allows real-time scheduling and monitoring of procedures.Furthermore a distribution transformer was fitted with temperature sensors andheat run tests were performed. The results of the temperature tests were used toverify the estimation techniques and to determine constants used for temperatureestimation.

[发布机构] Stellenbosch University