US3509267A - Multipurpose insulating column - Google Patents

Description

April 28 1970 O. 'JIENSENV 3,509,257

' MULTIPURPOSE INSULATING COLUMN v Filed Jan. 22, 1968 2 Sheets-Sheet 1 5g Hz 30 CONTROL April 28, 1970 o. JENSEN 3,509,267

I MULTIPURPOSE INSULATING COLUMN Filed Jan. '22, 1968 I 2 Sheets-Sheet 2 United States Patent 3,509,267 MULTIPURPOSE INSULATING COLUMN Otto Jensen, Malvern, Pa., assignor, by mesne assignments, to I-T-E Imperial Corporation, Philadelphia, Pa., a corporation of Delaware Filed Jan. 22, 1968, Ser. No. 699,624 Int. Cl. H01b 17/36 US. Cl. 17430 9 Claims ABSTRACT OF THE DISCLOSURE An insulating column which, by the nature of its construction, is capable of performing a number of functions, such as: supporting mechanism thereabove; electrically insulating such mechanism from the potential at the opposite end of the insulator; supporting a plurality of elements intermediate the ends of the insulator; protectively housing components which pass through the interior of the insulator; together with compressed gas and associated bellows, maintaining such various components in tension at all times; functioning as a conduit by continuously and insulatively conveying such compressed gas from one potential level to another; and at the same time making available a small amount of that compressed gas to inflate gaskets which seal the mechanism supported upon the insulator.

This invention relates to insulating columns and, more particularly, to an insulating column which, by way of the novel construction thereof, performs a multitude of functions.

Insulating columns have been used for many, many years to maintain elements at one potential safely away from areas, such as ground, of a differing potential. The insulating column of the instant invention similarly performs this basic function, but, in addition, because of the novel construction, performs a host of other functions dependent upon the particular system in which the insulating column is being utilized.

Accordingly, it is an object of the instant invention to provide a multipurpose insulating column.

Another object of the instant invention is to provide such an insulating column which will insulatively support mechanisms thereon.

Still another object of the instant invention is to provide such a multipurpose insulating column which will support various components intermediate the ends of the column.

Another object of the instant invention is to provide such a column which will protectively house various components passing therethrough.

Yet another object of the instant invention is to provide such a column which will maintain the aforementioned components in tension at all times.

Yet another object of the instant invention is to provide such a column which will function as part of a conduit system in communicating compressed gas between the ends of the column.

Other objects of the instant invention may be had by referring to the following description and drawings in which:

FIGURE 1 shows an embodiment of the multipurpose insulating column of the present invention as it might be embodiment of the multipurpose insulator column of the present invention. In order to put this invention in proper perspective, and in order to make its disclosure both understandable and meaningful, the colum will be described as it might be used in a protective system for a capacitor bank in a high voltage transmission line. Although described in this environment, it will be apparent that other systems can employ the insulator column of the invention, without departing from the spirit and scope of its teachings.

Broadly speaking, the purpose of a protective system of the type here in question is to protect a capacitor bank from the various abnormalities which may occur within the bank or along a transmission line, either in a single phase system or in a multi-phase system. Being more specific, it may be appreciated that the occurrence of severe faults within the transmission line (such as those which occur during short circuit) require that the capacitor bank be instantaneously removed from the line itself. One apparatus which can be utilized to effectuate such operation includes a spark gap in parallel with the capacitor bank, with the spark gap being designed to instantaneously are over once a predetermined voltage, proportional to the line current, is applied across the bank. When the gap fires, a low impedance path is established in parallel with the capacitor bank to'etfectively remove the capacitor bank from the transmission line.

The protective arrangement in which the present invention is described incorporates such spark gap operation to by-pass the capacitor bank in the event of instantaneous fault within the transmission line. Thus, a pair of doubleended spark gaps may be inserted in a parallel path with the capacitor bank being designed to arc over and thereby by-pass the capacitor bank upon the occurrence of a predetermined potential. However, these spark gaps are of'a nature as to continue to conduct current (even when the fault has subsided) until they are extinguished.

One method of extinguishing the arc is to direct a blast of compressed gas into the spark gap. Compressed air, for example, may be stored on a platform which supports the capacitor bank and the spark gaps, and is arranged to be released to extinguish the gap upon the activation of various control circuits, which are in turn responsive to detection devices which monitor the flow of current through the line. Thus, assuming that a fault of predetermined magnitude has occurred, the spark gap will arccontacts to release the compressed gas in the supply tov extinguish the arc and thereby reinsert the bank. Alternatively, these relays may actually block out mechanisms to permanently by-pass the capacitor bank in the event that the fault has not subsided within a predetermined time interval.

Such protective systems also include a compressor of some type to replenish the storage supply after an extinc- 'tion operation. This compressor might be located on the platform relatively close to the supply. However, it will be appreciated that if the compressor were located on the platform, it would be situated at platform potential (nearly equal to line potential) and would be unavailable for servicing and maintenance while the line was in service. To rectify the situation, the protective system can situate as many components as possible at ground level, operable at ground potential, with various means being provided to insulatively interconnect the various components situated at platform and ground respectively. Thus, the compressor may be situated at ground level with a conduit path being provided to insulatively interconnect the ground level components of the system, the compressor, the storage supply and the platform level elements of the protective arrangement.

A second aspect of the protective system in which the insulator column of the invention may be used relates to the provision of an auxiliary power supply to operate the various components of the gap extinction system. A voltage divider network operable from the transmission line can be employed in such a system to provide a first potential source at substantially platform potential which can operate components of the system which are situated on the platform, and can also provide a potential source which is relatively close to ground potential to operate those components of the system situated at ground level.

For example, the voltage divider may comprise a plurality of capacitors interposed in electrical series between the transmission line and ground, with the uppermost capacitor and a suitable step-down transformer providing operating potential for various control circuits at platform potential. The lowermost capacitor, on the other hand, when combined with a suitable stepdown transformer of like construction, can be employed to provide a relatively low potential power source for operating the various components of the system which are at ground level (such as the motor utilized to operate the compressor).

When overloads for a predetermined length of time exists in the protective system, a by-passing sequence can be provided in order to protect the capacitor bank. Means may also be provided to reinsert the capacitor bank once the abnormality has subsided. As before, such a protective system may be of the type to locate as many components as possible at ground level, with means being provided to insulatively interconnect the various components at ground level with the associated parts at platform potential. Thus, a by-pass switch arrangement may be situated in a parallel path, operable to by-pass and reinsert the capacitor bank by means of an operating mechanism which can be situated at ground level. Means, in the form of an insulative power rod may be employed to interconnect the contacts of the switch with the operating mechanism which controls it.

This brief description of a capacitor bank protective system is, as was previously described, presented only for purposes of setting the multipurpose insulator column of the invention in its proper perspective. Without such description, the construction and operation of the column would be less meaningful than for the case, as here, where the description is present. Although the insulator column itself is fully understandable as to its structure and without resort to additional disclosure, this brief description has been included for purposes of providing various information as to how the insulator column may be used and incorporated in an overall system.

Referring now more specifically to the drawings, there is shown a platform 22 insulatively maintained above ground by the insulator columns of the present invention, preferably comprising a plurality of stacks of individual insulator columns 162, the number of which would depend upon the voltage of the line being carried.

Supported upon the left-hand portion of the platform 22 is the capacitor bank 12 connected in series with the transmission line 10. The capacitor bank 12 is illustratively shown as comprising a plurality of individual capacitor units 14 arranged in series-parallel relationship to provide a desired reactance.

Supported upon an adjacent portion of the platform 22 is that portion of the protective system of FIGURE 1 which operates at platform potential. For example, a reactance 164 may be provided at platform potential to function as part of a current limiter during the occurrence of fault within the transmission line 10. Also, situated within a protective housing 168 is the previously described spark gap 16 situated upon the compressed gas storage supply tank 20, with the monitoring transformer and relays (not shown) associated therewith being in series between the spark gap 16. Also included within the protective housing 168 (though not shown) is the capacitive voltage divider previously described and the respective step-down transformers included to provide the operating potential required to operate the various control circuits which are at platform level and at ground level, as previously described. The by-pass and lock-out switch arrangements 62 and 150, respectively, are schematically shown as being housed in a cylindrical tube 170* at platform potential, with the terminals 172 and 174 of the tube being established in parallel about the spark gap 16 and capacitor bank 12. The by-pass lock-out tube 170 is supported upon a transition tube 176 to be described in greater detail, with the tube 176 being in turn supported upon the multipurpose insulator column 178 comprising the present invention. As indicated in the drawings, in sulator column 178 is in turn supported upon an enclosure 180 which houses the by-pass operating mechanism and lock-out operating mechanism 166 and 132, respectively, as well as the compressor of the system 30, all at ground level. Also shown at ground level is the stepdown transformer 54 which is connected in parallel with the lowermost capacitor 46 of the previously mentioned voltage divider, as well as the ground level control circuitry and various associated components operable by Considering column 178 in greater detail, it will be i seen that this unit is preferably comprised of a plurality of hollow modular insulator segments 182 stacked upon one another. Separating each of the modular components 182 is a supporting platform 186 which supports the various capacitors 40, 42 and 46 of the voltage divider. Thus, it will be seen that a first function of the insulator column 178 is to insulatingly support platform level by-pass and/or lock-out tube 170 with respect to ground. The second function of the column 178 is thus to support the capacitor units defining the voltage divider network, by which platform potential and ground potential energy sources are made available at either end thereof.

The drawings illustrate two further functions of the insulator column 178 in the protective system described. Thus, the by-pass operating mechanism 166 and the lockout power mechanism 132 are shown being situated beneath the insulator column 178 such that the by-pass and lock-out power rods 68 and 148, respectively, extend vertically up through the insulator column 178. These rods are thus able to cooperatively relate with the by-pass and lock-out switch means 62 and 150, schematically illustrated within the tube 170. Thus, the third function of the multipurpose insulator column 178 is to protectively house such power transferring rods which link the ground level mechanism and the associated platform level switches. Also, as shown in FIGURE 2, it will be seen that the insulating column employed protectively houses the signal rods, illustrated by reference numerals 92, 104 and 124.

Also, schematically illustrated in FIGURE 1 is the manner in which the column 178 performs another function associated with the protective system previously described. Specifically, the compressor 30 is situated beneath the column 178, such that the conduit path 32 includes as a portion thereof the hollow interior 188 of the column 178. That is, conduit 32 enters one sealed end of the hollow column 17 8 and is in communication with a relatively large interior hollow passageway 188. At the opposite end of column 178, the conduit tube 32 extends through the sealed end of the column 178 and continues through the tube 32 on its way to the storage tank 20 on platform 22. Thus, the enlarged hollow interior 188 of the column 178 may be thought of as an integral portion of the conduit 32, and continually aids in supplying gas from the compressor 30 to the storage tank 20 used in extinguishing the spark gap. In effect, then, another function of the insulator column 178 is to function as a pipe.

Finally, the insulator column 178 and the gas contained therein perform yet another function. To be more specific, the compressor 30 maintains the gas with hollow interior 188 of insulating column 178 under a substantially constant pressure. This compressed gas under pressure within insulator column 178 itself performs a dual function in that it more adequately insulates the by-pass and/or lock-out mechanism tube 170 from ground level; simultaneously, the pressure therein is utilized to maintain all the power rods and signalling rods passing therethrough in a state of constant tension to neutralize any buckling efiect they might experience in operation.

Turning to FIGURE 2, it will be seen that the insulating column 178 includes an inner tube 184, preferably made of wound glass filament bonded with epoxy resins. It is the inner tube 184 which is filled with compressed air, thereby increasing the internal dielectric strength of the hollow interior 188.

The ends of the tube 184 are circumferentially threaded at 190 to receive termination fittings 192 which perform a dual function. First, the termination fittings 192 secure the inner tube 184 to end flanges 194 and 196, with suitable gaskets 198 being provided between the ends of the tube 184 and the flanges 192 and 196, respectively, to provide an airtight seal therebetween. Secondly, the termination flanges 192 are made hollow as indicated at 200, so as to communicate with apertures 202 provided on the tube 184.

Thus, conduit 32 communicates with the compressor, at one end, and the lower termination fitting at the other end. Conduit 32A communicates with the storage tank 20 on the platform at one end, and the upper fitting termination 192 at the other end. Thus, the complete conduit path is established between the compressor at ground level and the tankat platform level, which conduit path includes the hollow interior 188 of the tube 184 as a portion thereof.

The inner tube 184 is protected by concentric glazed porcelain tube segments 182 interspaced by a plurality of capacitor support platforms 186 in the manner systematically suggested by FIGURE 3.

The space between the inner tube 184 and the outer shorter tubes 182 is filled with a compound 203, such as SF epoxy foam, to prevent surface condensation or the entrance of moisture that would impair the dielectric strength of the assembly.

The end flanges 194 and 196 project out of the outside radius of the tube segments 182. The total combined length of the outside tube segments 182 is made shorter than the inner tube 184, and compression springs 204 exert pressure between the flange 194 and the top of the last porcelain tube 182. This arrangement puts the porcelain segments 182 under compression and the inner tube 184 under tension, thus giving rigidity to the entire assemt3;- 6 bly and at the same time allowing for unequal thermal expansion.

FIGURE 2 also illustrates the manner in which the power rods 68 and 148 are protectively housed within the hollow interior 188 of insulating column 178 and the manner in which the rods pass through the flanges 194 and 196, respectively, into the ground housing 180 at one end thereof and into the signal and transition stage 176 at the other end thereof. Specifically, associated with each of the power rods 68 and 148 and at both ends of each rod, outside of the respective flanges 194 and 196, are individual bellows units 206, 208, 210 and 212. As shown in detail for the unit 212, each of the bellows units is sealed at one end 214 to the respective rod 68 and at the other end to a cylindrical jacket 216 which is rigidly positioned in an associated aperture in the flange 194. The diameter of the power rod is slightly less than the inside diameter of the cylindrical jacket 216, whereby such power rod is free to slide.

It will be appreciated that the bellows arrangement described performs a dual function. First of all it performs the obvious function of maintaining the sealed integrity of the interior 188 of the column 178, while permitting the longitudinal displacement of the power rods therethrough. Secondly, it should be apparent that because of the slight difference in diameters of the rod and associated cylindrical jacket, a certain amount of compressed gas will escape the confines of the interior 188 into each of the bellows. Considering for example by-pass power rod 68, it will be apparent that such compressed gas in building up pressure against the interior of the bellows 210 and 212 will exert equal and opposite forces on the rod 68. Since the forces generated at each end of the power rod will be equal and opposite, they will have no net effect upon the transmission of power by the rod between the ground level operating mechanism and the platform level switch responsive thereto. However, these forces will always maintain the respective rods in tension at all times, thereby counterbalancing any possible tendency that such rods may have to buckle when'they are being utilized as conveyor of compressive force rather than the conveyor of tension forces.

Also, and in a manner to be disclosed immediately be-,

low, the insulator column 178 protectively houses the.

- protective system makes possible the transmission of information between platform potential and ground level, whereby necessary steps can be initiated at ground level to begin various warning, by-pass, and/ or lock-out operations. FIGURE 2 illustrates an arrangement for implementing such a signalling system, it being understood that although only one such signalling arrangement is illustrated, a plurality of such arrangements would be provided in accordance with the number of signals being transmitted between platform and ground. Thus, three such arrangements would be necessary in order to provide a warning signal, a by-pass signal and a lock-out signal. For ease of illustration, FIGURE 2 will be described with respect to the bypass signal.

Signal and transition compartment 176 is interposed between the insulating column 178 and the by-pass and/ or lock-out tube 170. Signal and transition compartment 176 is defined by a concentric cylinder 218 secured at one end to the lower flange 174 of the by-pass lock-out tube 170 and secured at the other end to a ring 220 interposed between the compression springs 204 and the uppermost porcelain tube 182. Extending between the flange 194 and the top end of the signal compartment 176 is a support post 222, which supports a platform 224, outstanding therefrom. Secured to and depending from the platform 224 is the by-pass relay which includes a generally E-shaped core 91 and an energizing coil 93. As-

sociated with the core 91 is a movable armature 95, which in turn is connected to the by-pass signal rod 92 by means of a link 97. The signal rod 92 passes through the interior 188 of the insulating column 178, emerges at the other end within the enclosure 180, and is connected in turn to the double pole switch 99 which comprises the normally open contact pair 90A and the normally closed contact 90B. With the coil 93 non-energized, the return spring 101 normally biases the signal rod 92 and armature 95 downwardly such that the contacts 90A and 90B remain in the normally open and normally closed position, respectively. Upon the occurrence of the various faults, as described earlier, such that coil 93 becomes energized, the armature 95, link 97 and signal rod 92 are drawn upwardly against the bias of spring 101 such that contact 90A closes while contact 90B opens to initiate the by-pass operation in the manner explained previously.

It may be pointed out that bellows 226 and 228 cooperate with respective ends of the signalling rod 92 and with cylindrical jackets 230 and 232, respectively, in the same manner that the various bellows 206, 208, 210 and 212 cooperate with the power rods 68 and 148. Thus, compresed gas from the hollow interior 188 of the insulating column 178 escapes into the bellows 226 and 228 to exert equal and opposite tensile forces on the signalling rod 92 to maintain it in tension at all times to counteract any possible buckling effect. Simultaneously, such equal and opposite forces will have no effect and in no way interfere with the operation of the signalling rod effectuated by either the return spring 101 or activation of the. coil 93.

In one embodiment of the invention, the multipurpose insulator column 178 emloyed a round insulating tube 170 of plastic material terminated at both ends in flat metallic flanges 172 and 174 that served as connection terminals and simultaneously provided heremetic seals at both ends of the tube. Preferably, the inside of the tube 170 was filled with an insulating gas such as SP maintained under pressure which assured that the by-pass switch contacts would be closed in the event that there was a failure in protective system.

Also, an inflatable gasket 240 was used to guarantee the seal between the tube 170' and the lower flange 174. This inflatable gasket 240- was supplied with compressed gas by a thin conduit 242, which communicated with a hollow interior 188 of the multipurpose insulator column 178 through a termination fitting 192 in much the same manner as the conduit 32 communicated with the interior of the column 188 to its respective termination fitting. Thus, another function of the gas under pressure within the insulator column 178 was to aid in sealing the tube 170.

Thus, there has been described a multipurpose insulating column capable, because of its construction, of performing a host of functions. It will be understood that while the present invention has been described in an environment wherein various rods interconnect mechanisms located at ground and platform potentials, the teachings of the instant invention could be used in the protective systems of different configurations, especially if such other systems dictate the use of such movable rods or their equivalents.

The embodiments of the invention in which an exclusive privilege or property is claimed are defined as follows.

1. A multipurpose insulating column comprising:

a hollow insulating tube;

first and second sealing means for closing first and second ends of said tube to define an interior of said tube;

said interior being filled with compressed gas to provide better insulation between said first and second ends;

conveying means cooperating with said first and second ends of said tube for including the interior of said tube as a portion of a conduit for conveying gas between said first and second ends;

said conveying means including termination fittings securing said first and second sealing means to said first and second ends of said tube, said termination fittings including hollow passageways passing therethrough which communicate with said interior;

a mechanism supported above said column requiring a sealing relationship between various parts thereof; inflatable gasket means positioned in sealing relation ship with said various parts; and

direct means communicating with said inflatable gasket means at one end and with said interior through one of said termination fittings at its other end whereby the compressed gas within said interior is also used to inflate said inflatable gasket means.

2. The multipurpose insulating column of claim 1 and further including insulative protective means surrounding said tube.

3. The multipurpose insulating column of claim 2 where said insulative protective means is shorter than said tube and further includes biasing means for maintaining said tube in tension and said protective means in compression.

4. The multipurpose insulating column of claim 2 wherein said insulative protective means comprises a plurality of modular segments separatingly stacked upon one another by a plurality of interposed platforms for supporting various components supported between the ends of said column.

5. The multipurpose insulating column of claim 4 wherein said tube protectively houses a rod interconnecting mechanism at opposite ends of said column.

6. The multipurpose insulating column of claim 5 wherein said rod passes through said first and second sealing means; and further including bellows means at each end of said tube cooperating with a respective one of said sealing means and an end of said rod for preventing escape of said compressed gas from said interior while still permitting slidable movement of said rod.

7. The multipurpose insulating column of claim 6 wherein a first end of each bellows means is sealingly joined to said respective end of said rod, and a second end of each bellows means is sealingly joined to said re spective sealing means; the interior of each of said bellows means connecting with the interior of said tube whereby the compressed gas will generate equal and opposite forces on each of said bellows to apply equal and oppositeforces on said rod to maintain it under tension.

8. A multipurpose insulating column comprising:

a hollow insulating tube;

first and second sealing means for closing first an second ends of said tube to define an interior of said tube;

said interior being filled with compressed gas to provide better insulation between said first and second ends;

insulative protective means surrounding said tube including a plurality of modular segments separatingly stacked upon one another by a plurality of interposed platforms for supporting various components supported between the ends of said column;

a rod protectively housed within said tube interconnect ing a mechanism at opposite ends of said column wherein said rod passes through said first and second sealing means; and

bellows means at each end of said tube cooperating with a respective one of said sealing means and an end of said rod for preventing escape of said compressed gas from said interior while still permitting slidable movement of said rod.

9. A multipurpose insulating column comprising:

a hollow insulating tube;

first and second sealing means for closing first and second ends of said tube to define an interior of said tube;

said interior being filled with compressed gas to pro vide better insulation between said first and second ends;

a rod protectively housed within said tube interconnecting a mechanism at opposite ends of said column wherein said rod passes through said first and second sealing means; and

bellows means at each end of said tube cooperating with a respective one of said sealing means and an end of said rod for preventing escape of said compressed gas from said interior while still permitting slidable movement of said rod.

References Cited UNITED STATES PATENTS 2,804,576 8/ 1957 Coggeshall et a1. 3,071,668 1/1963 Upton et a1. 200--148 X 3,236,982 2/1966 Gonek et a1. 174179 X FOREIGN PATENTS 687,113 5/1964 Canada. 917,920 2/1963 Great Britain.

10 LARAMIE E. ASKIN, Primary Examiner US. Cl. X.R. 174-139, 179

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