DD148688A1 - METHOD FOR CONTROLLING THE OPERATING BEHAVIOR OF OILISOLATED HIGH VOLTAGE UNITS - Google Patents

Abstract

Method and device for controlling the performance of oil-insulated high-voltage devices, in particular large transformers equipped with a compensating vessel in communication with the exhaust air. The performance of such devices depends on the type and amount of dissolved oil in the insulating oil. In order to be able to determine the presence and formation of these gases without the removal of insulating oil samples, an analysis of the mixture present in the air space of the compensating vessel Gebr is also made and closed by the specific gas contents on the gas content in Isolieroel. For this purpose, with closed Belueftungsleitung necessary for breathing the high-voltage equipment air exchange with the Auszenluft over locks u. measured and a part of the air cushion of the Ausgleichsgefaeszes in forced circulation via Meszgeraete directed to determine individual gas concentrations, the Meszwerte formed in a Meszwerterfassungseinheit, optionally evaluated and shared, preferably with other operating parameters of the high voltage device, e.g. the insulating oil temperature and the operating current, are displayed and / or recorded. An arrangement for carrying out is described.

Description

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Title of the invention

Method for controlling the performance of oil-insulated high voltage equipment

Field of application of the invention

The invention relates to a method for controlling the performance of oil-insulated electrical high-voltage equipment "in particular large transformers, which are equipped with a provided with a ventilation line compensating vessel, and an arrangement for carrying out the method.

Characteristic of the known technical solutions

It is known that can be derived from the analysis of the gas dissolved in the insulating statements about the performance of the high voltage equipment. For this purpose, oil samples are taken and the dissolved gases are determined quantitatively and qualitatively (Müller, Schliesing, Soldner: The Assessment of the Operational State of Transformers by Gas Analysis, Elektrizitätswirtschaft, 76 (1977) H. 11, pp. 345-349). Also known is an extraction device arranged directly on the high-voltage device with which an insulating oil sample of a specific size is drawn off and extracted. The extracted gas passes to the qualitative determination to an analyzer, while the oil is returned to the insulating oil tank (DE-AS 2,143,045).

In another known device, which is installed on the high voltage device, the insulating oil is degassed and over

the vacuum change in the device are drawn conclusions about errors in the high-voltage device (DE-AS 2,160,526). All known solutions assume that certain quantities of insulating oil are degassed and the gas released is analyzed.

In the practice of fault diagnosis of transformers, the identification and assessment of the time evolution of the fault gases is becoming increasingly important. From the temporal course of changes in concentration can be derived statements about possible progressive developments. For this reason, a constant control is sought. It has already been proposed, using a device arranged directly on the high-voltage device for determining the gas content, to remove insulating gas samples, degas, determine the gas volumes and to record them together with further simultaneously determined operating parameters such as insulating oil temperature, air pressure, air temperature and operating current and for a complex diagnosis of the operating behavior. This method also requires the removal of insulating oil samples »

Object of the invention

The aim of the invention is to gain statements about the operating behavior, in particular the presence and generation of faulty gases, without insulating oil sampling.

Explanation of the essence of the invention

Based on the fact that in high-voltage devices of the open design, d. h., In which the expansion tank is in communication with the outside air, as a result of temperature fluctuations is a constant transport of dissolved gases from the oil to the atmosphere recorded, the invention is based on the object to fulfill the objective with the help of an analysis of the running dream of the expansion tank existing gas mixture on the gas content, in particular fault gas content, in the insulating close

and thus to control the operating behavior. This is accomplished by continuously or at intervals passing a portion of the air cushion of the surge tank in the forced circulation via gauges for determining individual gas components. The necessary for breathing the high voltage device air exchange with the outside air is controlled with closed vent line via locks and measured. The analysis and measured values are converted in a measured value acquisition unit, optionally evaluated and in a known manner, preferably together with other operating parameters of the high voltage device, ζ. B. the insulating oil temperature and the operating current, displayed and / or recorded.

For carrying out the method, an air line with a multi-way valve is connected to the air space of the expansion tank, which connects the air space either via a lock with the outside air or the suction side of a pump at the pressure side in series measuring instruments for determining the different gas components. The gas outlet of the last meter is connected to another multiway valve which connects a second air duct opening into the air space either via a further lock with the outside air or with said gas outlet. The measurement outputs of the locks and meters are located on a Meßwerterfassungs- and processing unit, which in turn is coupled to display and recording devices. The invention has the advantage that with her already errors in the first emergence, z. B. by the oxygen concentration monitoring, and errors with low activities, such. B. by the hydrogen concentration monitoring, continuously detected and displayed immediately. The emergence of other (fault) gases can be detected in the same way, without the need for the extraction of oil samples is required.

embodiment

The detailed explanation is based on the drawing, which shows a block diagram of an arrangement with which the method according to the invention can be carried out. It is installed on an oil transformer 15, which has a surge tank 3, which communicates with the outside air by means of a belt discharge line 21. A silica gel filter 18 is intended to dehumidify the incoming air. The vent line 21 can be shut off by a valve 19. To the expansion tank 3, a thermoelectric air dryer 16 is connected in a known manner. The arrangement for carrying out the method is via two air lines 17; 20 coupled to the air space of the expansion tank 3. The air pipes 17; 20 are each at a multi-way valve 9; 10, so that when the ventilation line is shut off the air space 2 can be switched either in a measuring circuit or via locks 7; 8 can be connected to the outside air, being inhaled via the one air lock 7 and exhaled via the other lock 8 air or the resulting gas mixture in the air space 2 (if the valve 19 is closed). In the circuit circuit, a part of the air cushion of the expansion tank 3 is sucked by means of a pump 1 continuously or at intervals and guided by measuring devices 4 to 6 for the determination of Gaskon¬ rations and then returned to the air space 2. The necessary during breathing of the transformer air exchange is via the locks 7; 8 controlled and measured. The Meßgänge the locks 7; 8 and measuring devices 4 to 6 are located on a measured value acquisition unit 11; 12, in which the measured variables are detected, reshaped, reinforced and optionally evaluated. This unit 11; 12 is coupled to a display or recording device 13, by which the detected measured values are displayed or registered together, preferably with other operating parameters 14, such as air temperature, oil temperature and operating current.

The gas components from the air cushion above the expansion tank represent a measure of the gases dissolved in the insulating oil

and give information (along with the other operating parameters) about the condition of the transformer with respect to developing faults.

Claims (2)

invention claim 1. A method for controlling the performance of oil-insulated high-voltage equipment, in particular large transformers, which are equipped with a communicating with the outside air equalization tank and their performance is determined in the insulating oil, dissolved gases, characterized in that statements about the dissolved gases in the oil the determination and evaluation of existing in the air space of the expansion tank gases are obtained by the shut-off ventilation line necessary for breathing the high-voltage device air exchange with the outside air via locks and measured and a part of the air cushion of the expansion tank in forced circulation is passed through measuring instruments for determining individual gas concentrations , wherein the measured values in a Meßwerterfassungseinheit reshaped, optionally evaluated, and in a known manner together, preferably with other operating parameters of the high voltage device, ζ. Β. the insulating oil temperature and the operating current, displayed and / or recorded. 2. Arrangement for carrying out the method according to item 1, characterized in that to the air space (2) of the expansion vessel (3) an air line (17) with a multi-way valve (9) is connected, the air space (2) either via a lock (7) with the outside air or the suction side of a pump (1) connects to the suction side in series measuring instruments (4 to 6) for the determination of gas components, wherein the gas outlet of the last meter (6) connected to another multi-way valve (10) is that connects a second in the air space (2) opening air line (20) either via a further lock (8) with the outside air or with the gas outlet and that the measuring outputs of the locks (7; 8) and measuring instruments (4 to 6) on a Meßwerterfassungseinheit (11; 12), which is coupled to a display and / or recording device (13) for a plurality of input variables.