US3098891A - Apparatus for the preservation and regeneration of insulating oil for electrical apparatus provided with an oil reservoir - Google Patents

Apparatus for the preservation and regeneration of insulating oil for electrical apparatus provided with an oil reservoir Download PDF

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Publication number
US3098891A
US3098891A US3681660A US3098891A US 3098891 A US3098891 A US 3098891A US 3681660 A US3681660 A US 3681660A US 3098891 A US3098891 A US 3098891A
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United States
Prior art keywords
reservoir
oil
piston
liquid
cylinder
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Expired - Lifetime
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English (en)
Inventor
Paul Delguste
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Umicore NV SA
Original Assignee
ACEC SA
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Priority claimed from FR797977A external-priority patent/FR1237310A/fr
Application filed by ACEC SA filed Critical ACEC SA
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Publication of US3098891A publication Critical patent/US3098891A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/08—Cooling; Ventilating
    • H01F27/10—Liquid cooling
    • H01F27/12—Oil cooling
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/08—Cooling; Ventilating
    • H01F27/10—Liquid cooling
    • H01F27/12—Oil cooling
    • H01F27/14—Expansion chambers; Oil conservators; Gas cushions; Arrangements for purifying, drying, or filling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7287—Liquid level responsive or maintaining systems
    • Y10T137/7339—By weight of accumulated fluid

Definitions

  • This invention relates generally to electrical devices cooled with an insulating fluid and particularly to an apparatus for preserving the insulating and dielectric qualities of the insulating fluid and for decontaminating it.
  • an oil reservoir in electrical apparatus also creates a certain danger, tor example, in the event of a terminal breaking and possibly causing fire.
  • the oil expansion reservoir can empty itself on to the site of the defect and thus accelerate the destruction of the tapparatus.
  • the present invention has for a principal object to provide an apparatus which combines the advantages of the known devices and which further offers the possibility of continuous regeneration and decontamination of the oil.
  • the apparatus according to the invention permits the Patented July 23, 1963 ice maintenance of a high or partial vacuum on the surface of the oil in the reservoir, while maintaining in a reliable manner the atmospheric pressure or even a slightly higher pressure in the main tank of the electrical apparatus or device.
  • One advantage of the present invention is that the level of oil can rise freely in the reservoir.
  • the vacuum acting on the surface of the oil operates, in service, to eliminate the last traces of moisture or gases dissolved or entrained in the oil, and by reason of the pressure existing at the same time in the main tank of the electrical device formation of bubbles, which would reduce the dielectric properties of the oil, need not be feared.
  • the oil from the reservoir cannot pour out to add to the danger of fire.
  • the apparatus for preservation and regeneration of insulating oil for electrical devices provided -With an oil reservoir communicating with the exterior through a pipe, which may contain a dryer or dehydrator, is characterised in that the admission of oil from the reservoir, in which a low pressure obtains, to the main tank of the apparatus, in which atmospheric or slightly higher pressure obtains, is effected by a pump controlled by the actual variations of the oil volume in the main tank.
  • the flow of oil from the main tank to the reservoir is effected through a delivery valve, the opening of which is also controlled by the variations of the oil volume in the main tank of the oil-cooled device.
  • the valve controlling means responsive to the variations of the volume of oil in the tank, preferably comprises a piston reciprocable in a cylinder connected directly to the main tank and it includes means for controlling the pump and means for controlling a delivery valve.
  • the upper part of the oil reservoir above the oil level has no communication with the exterior or atmosphere except through an escape val-ve permitting the escape of gases or air above the oil level and communication with the atmosphere can be established through a dehydrator to which the communication is controlled by the movements of the piston, but access or communication thereto is closed in normal operation.
  • the means for regulating a delivery valve to the reservoir is constituted by a piston responsive to the variations of the oil volume in the main oil tank of the oil-cooled device.
  • the cylindrical surface of this piston is utilized as the means for opening and closing the delivery valve.
  • FIG. 1 is a schematic elevation view, partly in section, of an apparatus according to the invention
  • FIG. 2 is a fragmentary, sectional, detail view of an other embodiment of a pressure-responsive element for sensing oil volume variations in the apparatus shown in FIG. 1;
  • FIG. 3 is a schematic elevation View, partly in section, of another embodiment of the apparatus shown in FIG. 1.
  • an apparatus for preserving the insulation and dielectric properties of insulating oil and for regenerating the insulating oil of a main oil tank (not shown) of an oilinsulated device for example, an oil-cooled transformer (not shown)
  • an oil reservoir 1 to which is connected a motor-driven oil pump 2 and a cylinder 3 in which a delivery valve is operable as hereinafter explained for allowing oil flow from the main oil tank into the reservoir.
  • the cylinder 3 is provided with connection line 6 providing communication between the interior of the cylinder and the main oil tank of the transformer (not shown).
  • the cylinder 3 is provided with means responsive to variations of the volume of the oil in the main oil tank comprising a piston 7 reciprocable in opposite directions in the cylinder 3.
  • a valve 4 is provided with a long valve stem 9 extending into the piston and having a shoulder 10 which is engaged by the piston for unseating the valve 4 as later herein explained.
  • the piston is provided with a rod internally of the skirt thereof in the form of a tail rod 12 provided with a cam 12a for starting and stopping the oil pump 2 in response to variations in the volume of the oil in the main tank.
  • the pump 2 is connected to the reservoir 1 and the cylinder 3 through lines 14 and 15 between which is disposed a non-return valve 17 and branch lines 15, 20 connected downstream and upstream of the non-return valve 17 respectively.
  • the line 20 is a discharge line from the pump and a non-return valve 21 is disposed therein. Both non-return valves allow oil flow in the direction toward the cylinder 3 and to the main oil tank.
  • the ratio of the pump delivery to the maximum intake of the main tank, which takes place in cold weather and on total shutdown of the load on the device or transformer, is calculated in such a way that the pumping cycles succeed one another at a sufficiently slow rate.
  • the intake through the line 6 progressively raises the piston 7 again.
  • the piston at a given moment, unmasks an opening 30 which allows the vacuum in the reservoir to be broken by permitting atmospheric air to enter the reservoir through the opening 30, a drier 31 and the line 28.
  • the travel of the piston 7 between its normal position and the position at which it unmasks the opening 36 determines a reserve volume of oil which retards the breaking of the vacuum in the reservoir in the event of failure of the pump 2.
  • the valves 17 and 21 being subjected on both sides to the same pressure, can open to permit circulation of oil from the reservoir to the main tank.
  • the reservoir operates like a normal reservoir provided with an air vent, and the flow of oil takes place towards the main tank through the line 14, the valve 17 and the line 6, as well as by any leakages in the pump 2 and at the valve 21.
  • This arrival of oil returns the piston 7 into the position shown in the drawing, and the cycle will recommence.
  • the ratio of the rate of flow of oil into the main tank to the volume of the cylinder 3 is calculated so that the opening 30 is only unmasked after a failure of current, in the motor driving the pump, of a sufiiciently long and predetermined duration.
  • the air drier 3 1 is only placed in communication with the atmospheric air in the event of failure of the oil pump, thus its drying properties are kept at a maximum.
  • the reservoir 1 is almost constantly under vacuum, or, if not, under a reduced pressure due to a slow outflow of oil through line 14, valve 17, line 15 and an upper space 32 of the cylinder 3 and out line 6 or through lines 14, 19, the pump 2 and valve 21, line 15, the space 32 and line 6. Because of this the oil in the reservoir will not run out upon rupture of the main tank, breakage of terminals or some similar accident. In fact, in such a case, the valves 17 and 2 1 close firmly on their seats and an out-flow from the reservoir is prevented. The air rushing in through the tank opening or rupture will replace the oil in the top end space 32 of the cylinder 3 and in the line 15 leading to the reservoir.
  • the piston 7 is not subjected to pressure or vacuum, but only to the weight of the oil contained in the cylinder 3 up to the lower edge of the line 6.
  • the piston then remains in the position shown in the drawing, since this weight of oil is not suflicient to overcome the force of the spring .24.
  • the valve 4 therefore remains closed and the oil from the reservoir 1 cannot ilow towards the main tank.
  • the apparatus is prefer-ably provided with a motordriven vacuum pump shown schematically at 34 connected to take a vacuum drag on the reservoir or expansion tank :1 above the level of the oil therein.
  • the pressure in the reservoir can always be kept below a predetermined value, which greatly improves the effectiveness of the reservoir as a degasifier and dehydrator.
  • the vacuum pump 34- is preferably controlled by the piston rod 12 by means of a cam 12b thereon which closes a switch 36 when the delivery valve 4 opens.
  • the closing of switch -36 electrically energizes the motordriven vacuum pump 34 from the electrical supply circuit as shown.
  • a manometer 37 which senses the pressure above the oil level in reservoir 2 and operates a switch 38 in series with the switch 36. When the pressure is low the manometer opens the switch 38.
  • a deformable elastic diaphragm 40 of known type as shown in FIG. 2.
  • the masking of the orifice or opening 36 leading to the air drier 31 can be effected by the deformable diaphragm covering the opening 30'.
  • This arrangement is equivalent to a valve and permits the elimination of the valve 29 as shown in FIG. 1. The air expelled from the reservoir by expansion of the oil is then compelled to pass first into the drier 31 before being released to the exterior, but this presents no great disadvantage.
  • the apparatus for oil preservation and regeneration is connected to the main tank (not shown) of a transformer by means of a line '6' and it comprises a reservoir 1', a motor-driven oil pump 2', a device responsive to variations of the volume of oil contained in the closed main tank of the transformer, and a delivery valve iormed by an opening 41 in a line 26" in conjunction with a piston 7'.
  • the device responsive to the variations of the oil volume is constituted by a cylinder 3' into which the pipe 6 opens, and said piston 7.
  • the piston 7' is provided with an element, in the present case a head rod 12. provided with a cam 12a for starting and stopping the pump 2. according to the variations of the oil volume in the closed main tank, which variations are measured by the position of the piston 7 in the manner heretofore described with respect to the embodiment in FIG. 1.
  • the means for controlling the delivery valve is constituted by the piston 7 itself, since the cylindrical walls of its skirt form a slide valve for the opening and closing of the opening -41.
  • the pump 2' is controlled by switch 22 and the valves 17', 21' and line 114' here carry out the same rfunctions as already described with reference to their corresponding parts in FIG. 1.
  • the pressure in the transformer tank is always equal to the atmospheric pressure obtaining above the piston 7' plus the weight of the piston and of the column of oil contained in the line 6 and in a space 32 inside the cylinder 3'.
  • a groove 46 situated near the top of the piston, is placed in communication with the oil beneath the piston through a small bore passageway 47.
  • This groove 46 is thus constantly filled with oil, and in the event of a defect in the tightness of the piston, it is this oil which is sucked into the reservoir, and not atmospheric air.
  • the dimensions of the reservoirs -50 and 51 and the quantity of oil which they contain is so determined that in case the reservoir 1 is placed under atmospheric pressure, dried air which has been dehydrated by the drier 55' will bubble through the oil, in passing from the reservoirs 50,
  • the Weight of the piston 7 and the clearance between that piston and the cylinder wall are determined in such a way that the highest level reached by the oil between those parts is above the groove 46 but not above the top of the piston.
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having an expansion reservoir comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, means comprising a valve and a piston reciprocable in said cyiinder for operating said valve in response to volume variations of said insulating liquid in said device and movable in one direction for controlling liquid flow into said reservoir when the liquid in said device expands and flows in a direction toward said reservoir and movable in an opposite direction for controlling flow of liquid from said reservoir to said device when the liquid contracts and flows in a direction toward said device, a fluid pump in communication with said reservoir and said cylinder, means for intermittently operating said pump in response to a preselected range of positions of said piston for pumping liquid from said reservoir to said device to maintain ⁇ a preselected volume of insulating liquid in said devim, means for creating a partial vacuum in said reservoir comprising a vacuum pump in communication with said reservoir, means actuated by said piston to intermittent
  • Apparatus tor preserving and regenerating insulating liquid for liquid-cooled electrical devices having an expansion reservoir under a partial vacuum comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, means comprising a delivery valve and a piston operably connected to said valve and recip-rooable in said cylinder in response to volume variations of said insulating liquid in said device and movable in one direction for controlling liquid flow into said reservoir when the liquid in said device expands and flows in a direction toward said reservoir and in an opposite direction for controlling flow of liquid from said reservoir to said device when the liquid contracts and flows in a direction toward said device, and a pump in communication with said reservoir and said cylinder, means for intermittently operating said pump in response to a preselected range of positions of said piston tor pumping insulating liquid, froml said reservoir to said device to maintain a preselected volume of insulating liquid in said device, means to periodically increase the vacuum in said reservoir to a preselected value under control of
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having a liquid expansion reservoir under a partial vacuum comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, a piston reoiprooable in said cylinder in response to volume variations of said insulating liquid in said device, a valve operable to an open position by said piston in one direction of travel thereof for allowing liquid to flow into said reservoir when the liquid in said device expands and flows in a direction toward said cylinder and operable to a closed position by said piston in its other direction of tnavel when liquid in said device contracts and flows in a direction toward said device, said means providing communication between the pump and cylinder comprising a pump, a one-way series-valve connected in series with said pump and another one-way valve connected in parallel with said pump and said series valve, and means for intermittently operating said pump in response to a preselected range of positions of said piston for pumping insulating liquid from said reservoir
  • Apparatus according to claim 3 including means actuated by said piston in dependence upon its travel exceeding a predetermined range of positions for placing said reservoir in communication with the atmosphere for allowing the liquid to flow from the reservoir to said cylinder and said device through said valve connected in parallel.
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having a liquid expansion reservoir comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, means comprising a piston reciprooable in said cylinder in response to volume variations of said insulating liquid in said device and movable in one direction for controlling liquid flow into said reservoir when the liquid in said device expands and flows in a direction toward said reservoir and movable in an opposite direction for controlling flow of liquid from said reservoir to said device when the liquid contracts and flows in a direction toward said device, valve means controlled by said piston for controlling said liquid flow, a fluid pump in communication with said reservoir and said cylinder, means for intermittently operating said pump in response to preselected positions of said piston for causing said pump to pump liquid from said reservoir to said device to maintain a preselected volume of insulating liquid in said device, means for creating a partial vacuum in said reservoir comprising a vacuum pump in communication with said reservoir, and means actuated by said
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having an expansion reservoir comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, means comprising a valve and a piston reciprocable in said cylinder for operating said valve in response to volume variations of said insulating liquid in said device and movable in one direction for controlling fluid flow into said reservoir when the liquid in said device expands and flows in a direction toward said reservoir and movable in an opposite direction for controlling flow or" liquid from said reservoir to said device when the fluid contnacts and llows in a direction toward said device, a pump in communication with said reservoir and said cylinder, means for intermittently operating said pump in response to a preselected range of positions of said piston for causing said pump to pump liquid from said reservoir to said device to maintain a preselected volume of insulating liquid in said device, means for creating a partial vacuum in said reservoir comprising a vacuum pump in communication with said reservoir and means actuated by said
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having an insulating liquid expansion reservoir comprising, an expansion cylinder, means providing a communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, a piston reciprocable in said cylinder in response to volume variations of said insulating liquid in said device, first valve means operable by said piston to an open position allowing liquid to flow into said reservoir when the liquid in said device expands and operable by said piston to a closed position
  • one-way valve means connected to allow liquid to flow from said reservoir through said means providing communication between said cylinder and said reservoir .to said cylinder toward said device when the liquid contracts, a pump in communication with said device and said reservoir, and means for operating said pump intermittently in response to preselected positions of said piston for causing said pump to pump liquid from said reservoir to said device to maintain a preselected volume of insulating liquid in said device.
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having an insulating liquid expansion reservoir comprising, an expansion cylinder, means providing communication between said cylinder and said device and means for providing communication between said cylinder and said reservoir, a piston reciprooable in said cylinder in response to volume variations of said insulating liquid in said device, first valve means connected to said piston operable to an open position for allowing liquid to flow from said device into said reservoir when the fluid in said device expands and operable to a closed position when the liquid in said device contracts and in the event of loss of fluid our of said device, one-way second valve means disposed in said means providing communication between said cylinder and said reservoir to allow insulating liquid no flow in a direction only from said reservoir through said cylinder to said device when the liquid contracts and in the event of loss of said device, whereby said first and second valve means provide communication between the reservoir and :the cylinder and are operable to "a closed position for maintaining the liquid in said reservoir in the event of fluid ioss out or said device
  • Apparatus for preserving and regenerating insulating liquid for liquid-cooled electrical devices having an insulating liquid expansion reservoir comprising, an expansion cylinder, means providing communication between said cylinder and said reservoir, a first valve, a piston operably connected to said first valve and recipnocable in said cylinder in response to volume variations of said insulating liquid in said device and movable in one direction tfior controlling liquid flow through said first valve into said reservoir vvhen the liquid in said device expands and flows in a direction toward said cylinder and said reservoir, second valve means for allowing the liquid to flow only from said reservoir to said device when the liquid contracts and flows in a direction toward said device, and a pump in communication with said reservoir through said means providing communication between said cylinder and said reservoir to said device when the liquid contracts and flows in a direction toward said device, and a pump in communication with said reservoir and said cylinder intermittently operable in response to preselected positions of said piston fior pumping liquid from said reservoir to said device to maintain a pre selected volume of insulating liquid in

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Compressors, Vaccum Pumps And Other Relevant Systems (AREA)
  • Drying Of Solid Materials (AREA)
  • Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
  • Compressor (AREA)
US3681660 1959-06-18 1960-06-17 Apparatus for the preservation and regeneration of insulating oil for electrical apparatus provided with an oil reservoir Expired - Lifetime US3098891A (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
FR221649T 1959-06-18
FR797877A FR1237288A (fr) 1959-06-18 1959-06-18 Dispositif de préservation et de régénération de l'huile pour les appareils électriques munis d'un conservateur
FR797977A FR1237310A (fr) 1959-01-20 1959-06-18 Chronomètre avec dispositif de jeu
FR804395A FR76279E (fr) 1959-06-18 1959-09-04 Dispositif de préservation et de régénération de l'huile pour les appareils électriques munis d'un conservateur

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US3098891A true US3098891A (en) 1963-07-23

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US3681660 Expired - Lifetime US3098891A (en) 1959-06-18 1960-06-17 Apparatus for the preservation and regeneration of insulating oil for electrical apparatus provided with an oil reservoir

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US (1) US3098891A (fr)
AT (1) AT221649B (fr)
BE (1) BE591502A (fr)
CH (1) CH369820A (fr)
DE (1) DE1121720B (fr)
FR (2) FR1237288A (fr)
SE (1) SE184918C1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4234754A (en) * 1978-02-28 1980-11-18 Bicc Limited Oil-filled electric cable installations comprising pressurizing oil tanks
US4390858A (en) * 1980-03-31 1983-06-28 Transformatoren Union Aktiengesellschaft Liquid-cooled transformer for large power ratings
US4967832A (en) * 1989-12-27 1990-11-06 Nrc Corporation Cooling method and apparatus for integrated circuit chips
DE102012203502A1 (de) * 2012-03-06 2013-09-12 Siemens Aktiengesellschaft Gehäuseanordnung für ein Aktivteil einer elektrischen Maschine
US20230326651A1 (en) * 2020-09-18 2023-10-12 Hitachi Energy Switzerland Ag Housing part, electrical system and operating method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1642406A (en) * 1923-02-05 1927-09-13 Buchholz Max System of protection of electric apparatus
US1970393A (en) * 1929-11-22 1934-08-14 Gen Electric Method of and means for connecting reservoirs to fluid filled cables
US1991368A (en) * 1933-09-02 1935-02-19 Okonite Callender Cable Co Inc Electric power cable
US2220728A (en) * 1939-04-04 1940-11-05 Gen Electric Means for controlling liquid pressure in riser cables
US2639309A (en) * 1950-03-20 1953-05-19 Savoisienne Const Elec Safety device for transformers with oil reservoir

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1642406A (en) * 1923-02-05 1927-09-13 Buchholz Max System of protection of electric apparatus
US1970393A (en) * 1929-11-22 1934-08-14 Gen Electric Method of and means for connecting reservoirs to fluid filled cables
US1991368A (en) * 1933-09-02 1935-02-19 Okonite Callender Cable Co Inc Electric power cable
US2220728A (en) * 1939-04-04 1940-11-05 Gen Electric Means for controlling liquid pressure in riser cables
US2639309A (en) * 1950-03-20 1953-05-19 Savoisienne Const Elec Safety device for transformers with oil reservoir

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4234754A (en) * 1978-02-28 1980-11-18 Bicc Limited Oil-filled electric cable installations comprising pressurizing oil tanks
US4390858A (en) * 1980-03-31 1983-06-28 Transformatoren Union Aktiengesellschaft Liquid-cooled transformer for large power ratings
US4967832A (en) * 1989-12-27 1990-11-06 Nrc Corporation Cooling method and apparatus for integrated circuit chips
DE102012203502A1 (de) * 2012-03-06 2013-09-12 Siemens Aktiengesellschaft Gehäuseanordnung für ein Aktivteil einer elektrischen Maschine
US20230326651A1 (en) * 2020-09-18 2023-10-12 Hitachi Energy Switzerland Ag Housing part, electrical system and operating method

Also Published As

Publication number Publication date
FR76279E (fr) 1961-09-29
BE591502A (fr) 1960-10-03
DE1121720B (de) 1962-01-11
FR1237288A (fr) 1960-07-29
AT221649B (de) 1962-06-12
SE184918C1 (sv) 1963-09-03
CH369820A (fr) 1963-06-15

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