Patent ID: 8442775

Claim:
A system for monitoring dissolved gases in high voltage equipment immersed in insulating oil, the system comprising: a cylindrical rigid rod ( 2 ), endowed with an anchorage device ( 3 ) for its fixing to an orifice ( 4 ) which gives access to oil (O) of the high voltage equipment ( 5 ); for a lower end ( 6 ) of the rod ( 2 ) inserted through the orifice ( 4 ) until it reaches a place where there is a natural oil circulation (O); two orifices ( 7 , 8 ) diametrically opposed at the lower end ( 6 ) of the rod ( 2 ), one for oil inlet ( 7 ) and the other for oil outlet ( 8 ); tubing ( 7 ′, 8 ′) of oil circulation connected to these orifices ( 7 , 8 ), that are axially placed inside the rod ( 2 ) and parallel to each other; the upper end of the rod ( 2 ) to he rigidly fixed to a main body ( 9 ), inside of which there are two oil chambers ( 10 , 11 ), each one connecting to the tubing ( 7 ′, 8 ′), both oil chambers ( 10 , 11 ) being interconnected at their upper parts by means of a pump ( 12 ) of oil circulation, which is controlled by the micro-processor ( 13 ), which switches it on and off according to a program present in its software ( 14 ); wherein the oil pump ( 12 ), when in operation causes oil (O) circulation, which enters through the inlet orifice ( 7 ), moves through the inlet tubing ( 7 ′), enters into the first oil chamber ( 10 ), passes through the pump ( 12 ), enters into the second oil chamber ( 11 ), passes through outlet tubing ( 8 ′) and returns to the high voltage equipment ( 5 ) after having left the discharge orifice ( 8 ); wherein each of the oil chambers ( 10 , 11 ) have one or more of their walls constituted by membranes ( 17 , 18 ) made of semi-permeable material, that allow dissolved gas in oil (O) to permeated into gas chambers ( 10 ′, 11 ′), that are interconnected by channel ( 19 ); at least one sensor ( 20 ) by the gas chamber ( 10 ′) for measurement of a concentration of concerned gases intended to be monitored, gas chambers ( 10 ′, 11 ′) being hermetically sealed, making gases concentration in its inside directly proportional to the concentration of dissolved gases in the oil (O), such that concentration measurements made by the sensors ( 20 ) may be used by the micro-processor ( 13 ) for calculations in its software ( 14 ) of the same gases in oil (O) concentration; an air pump ( 12 ′), that, by means of the inlet ( 23 ) and exhaust ( 26 ) check valves obtains oxygen from the atmospheric air (A) to assure oxygen presence in the gas chambers ( 10 ′, 11 ′), the air pump ( 12 ′) being controlled by the micro-processor ( 13 ), that switches the air pump ( 12 ′) on and off in an intermittent and cyclic manner, according to a program present in the software ( 14 ) processed by the micro-processor ( 13 ).