Electricity: measuring and testing – Electrolyte properties – Using a conductivity determining device
Patent
1993-06-11
1995-01-31
Wieder, Kenneth A.
Electricity: measuring and testing
Electrolyte properties
Using a conductivity determining device
324552, 324694, 324722, 174 153, 174 11BH, G01N 2706
Patent
active
053861922
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to an apparatus for checking the contamination condition of electric insulators installed in the open in a given area, for instance the insulators of an electric station or sub-station.
In the following description, with insulators we intend those units made of porcelain, glass or other suitable insulating materials that afford the electrical insulation between two parts at different voltage of an open air electric plant.
A thorough checking of the contamination conditions of the external surfaces of such insulators allows the piloting of cleaning actions on the same insulators. It is noted that a drop in the insulating properties of an insulator also occurs when the contaminator deposit on its surface exceeds the critical threshold that depends on the shape and size of the insulator and on the voltage applied. This has led to the demand for an indicator of the quantity of contaminator deposit to be found on one insulator representative of a group of insulators installed within the same area and able to signal the moment in which said layer of deposit reaches the critical threshold and thus to activate the cleaning system action or, in absence of the latter, the start up of a cleaning action of the insulator group with voltage disconnected. In the description that follows we shall call "the probe-insulator" an insulator that is representative of the group of insulators in the same area, group that will normally be made up of insulators of different type and shape.
It appears that there are no such quantity indicators installed in Italy, but elsewhere there are apparatus that function as quantity indicators of the contaminator deposit. A first system is noted, comprising a probe-insulator exposed at a given height from the ground in the plant area and that is periodically lowered into an underlying tank so as to be washed in the water with the help of auxiliary means such as ultrasonic waves and the rotation around its axis of the insulator itself. All the contaminator materials deposited on the probe-insulator's surface gets washed into the water. At the end of each periodic wash the volume conductivity of the solution is measured, and this, naturally, tends to increase after each wash. In one instance comes the time when the measured value for conductivity is equal to the pre-set critical threshold. A second system is also noted that comprises a probe-insulator that, after being exposed, again at a certain height within the plant area, is periodically lowered and closed into a chamber in which steam, produced by a steam generator, humidifies the contaminator layer on the surface of the probe-insulator. Then the conductivity of this layer is measured and compared with the pre-set critical threshold.
A common disadvantage of both these systems consists in the mechanical complexity required for the automatic performance of the operative stages. For example, both the washing chambers and the humidifying chambers need devices for their opening and closing; especially the first must be kept closed and must open only for the time necessary to allow the entrance of the probe-insulator, and the systems must comprise mechanisms and control means for the movements of the probe-insulator relatively to the chambers. Another disadvantage of the first system relates to the fact that its use is limited to those cases in which the contaminator is easily soluble in water, as are generally marine pollutants. Another disadvantage pertaining to the second system is the need to adjust the steam generator in relation with the environmental conditions and the fact that this adjustment is made more complex and of uncertain result because the system works in the open; moreover, experience has proved the difficulty of completely humidifying the contaminator layer and, at the same time, avoiding that this layer be partly or totally washed away.
The invented apparatus obviates the aforementioned disadvantages and, as claimed, comprises: a probe-insulator featuring an internal cavity; a first system for t
REFERENCES:
patent: 3627899 (1971-12-01), Moore
patent: 3807489 (1974-04-01), Minbiole et al.
patent: 4101828 (1978-07-01), Dehler
patent: 4132853 (1979-01-01), Wagenaar
patent: 4169965 (1979-10-01), Cronin
patent: 4237415 (1980-12-01), Easley
patent: 4358631 (1982-11-01), Matsuda
patent: 5136856 (1992-08-01), Yamamoto et al.
Brown Glenn W.
ENEL-Ente Nationale per l'Energia Elettrica
Wieder Kenneth A.
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