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Abstract
The work reported in this thesis is concerned with the design, development and
testing of a wireless 802.11 condition monitoring sensor for an electrical substation
environments. The work includes a comprehensive literature review and the design and
development of a novel continuous wireless data acquisition sensor. Laboratory and
field tests were performed to evaluate the data acquisition performance of the developed
wireless sensor. The sensor‟s wireless immunity to interference performance was also
evaluated in laboratory and field tests.
The literature survey reviews current condition monitoring practices in electrical
substation environments with a focus on monitoring high voltage insulators and
substation earth impedance.
The data acquisition performance of the wireless sensor was tested in a
laboratory using two artificially polluted insulators, in a fog chamber that applied clean
fog. Analysis of the test results were found to be in good agreement with those recorded
directly through a data acquisition card and transmitted via coaxial cable. The wireless
impedance measurement of a 275kV transmission earth tower base field test was also
performed and was found to be in agreement with previous published results from
standard earth measurements.
The sensor‟s wireless interference performance was evaluated at a field test site
when no high voltage experiments were taking place. The sensors wireless interference
performance was then tested in a laboratory environment before and during high voltage
tests taking place. The results of these tests were compared to each other and to
published results. These tests demonstrate the suitability of the sensor‟s design and its
immunity to interference.
The experimental work conducted using the developed wireless sensor has led to
an understanding that continuous wireless data acquisition is possible in high voltage
environments. However, novel condition monitoring systems that make use of such
wireless sensors, have to take into account data losses and delays adequately.
Furthermore, a solar power source was designed and constructed to be used for
outdoor substation applications and the solar battery charging performance of the
wireless sensor was tested in a solar laboratory.
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