WO2019154332A1

WO2019154332A1 - Transformer systems including transformer trucks

Info

Publication number: WO2019154332A1
Application number: PCT/CN2019/074476
Authority: WO
Inventors: Jiyuan XIN; Bin Huo; Dezhong Wang; Junjia SHEN; Xuhui REN
Original assignee: Industrial Connections & Solutions LLC
Priority date: 2018-02-09
Filing date: 2019-02-01
Publication date: 2019-08-15
Also published as: CN110137021A; WO2019154332A8

Abstract

A transformer truck for a transformer system is provided. The transformer truck defines a first direction, a second direction, and a third direction, the three directions orthogonal to each other. The transformer truck includes a housing and a grounding switch mechanism. The housing is arranged to receive a first transformer, the first transformer in a first orientation relative to the third direction and a laterally adjacent second transformer in a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. Thc grounding switch mechanism is coupled to the housing, is switchable between a non-grounded condition and a grounded condition, and includes a pair of grounding arms each coupled to respective inner portions of the housing and rotatable between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms.

Description

TRANSFORMER SYSTEMS INCLUDING TRANSFORMER TRUCKS

BACKGROUND

The field of the disclosure relates generally to transformer systems, and more particularly, to transformer trucks designed to improve the safety of transformer trucks within transformer systems and the packaging efficiency of electrical components within an clcctrical enclosure.

Transformers are common electrical components used in electrical distribution, transmission, and control systems to transform, for instance, an input voltage to a desired output voltage. Transformers may also be used to transform an input current to a desired output current. Known electrical distribution, transmission, and control systems may include electrical enclosures having switchgear including transformer trucks configured to house and carry transformers between multiple positions within the enclosure including, for example, an operational position and a service position. At least some known electrical enclosures permit an operator to move the transformer truck to the service position, or “rack out” a transformer truck with a door to the electrical enclosure open and the transformer in an energized state, potentially presenting a safety risk to the operator. Other known transformer trucks incorporate grounding foil to de-energize the transformers when the transformer truck is in the service position, but the grounding foil may become deformed after multiple uses and become ineffective at fully grounding the transformers within the transformer truck. Further, at least some known transformer trucks are configured to house transformers in an arrangement that inhibits the use of more than two transformers per transformer truck while remaining within Institute of Electrical and Electronics Engineers (IEEE) compact switchgear size requirements.

BRIEF DESCRIPTION

In one aspect, a transformer truck for a transformer system is provided. The transformer truck defines a first direction, a second direction, and a third direction, the three directions orthogonal to each other. The transformer truck includes a housing and a grounding switch mechanism. The housing is arranged to receive a first transformer, the first transformer in a first orientation relative to the third direction and a laterally adjacent second transformer in a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. The grounding switch mechanism is coupled to the housing and is switchable between a non-grounded condition and a grounded condition. The grounding switch mechanism includes a pair of grounding arms each coupled to respective inner portions of the housing and rotatable between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms.

In another aspect, a transformer system for an electrical cnclosure is provided. The electrical enclosure defines a first direction, a second direction, and a third direction, the three directions orthogonal to each other. The transformer system includes a transformer truck coupleable between a load side power line coupled to at least one electrical component and a line side power line coupled to at lcast one electrical power source. The transformer truck includes a housing, a plurality of transformers, and a grounding switch mechanism. The plurality of transformers are arranged within the housing, wherein a first transformer of the plurality of transformers has a first orientation relative to the third direction, and wherein a laterally adjacent second transformer of the plurality of transformers has a second orientation relative to the third direction, wherein the second orientation is oppositc to the first orientation. The grounding switch mcchanism is couplcd to the housing and is switchable between a non-grounded condition and a grounded condition. The grounding switch mechanism includes a pair of grounding arms each coupled to respective inner portions of the housing and rotatable between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms.

In yet another aspect a method of de-energizing a transformer is provided. The method includes moving a transformer truck along a carrier from an engaged position to a disengaged position. The transformer truck includes a housing and a grounding switch mechanism. The housing stores a plurality of transformers including a first transformer having a first orientation relative to the third direction, defined by the transformer truck, and a laterally adjacent second transformer having a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. The grounding switch mechanism is coupled to the housing and is switchable between a non-grounded condition and a grounded condition. The grounding switch mechanism includes a pair of grounding arms each coupled to respective inner portions of the housing and rotatable between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms. The method also includes switching the grounding switch mechanism from the non-grounded condition to the grounded condition to cause the grounding bar to contact grounding contacts on the plurality of transformers.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

FIG. 1 is a perspective and partial cutaway view of an exemplary embodiment of an electrical enclosure;

FIG. 2 is a schematic side view of an example embodiment of a transformer system that may be used with the electrical enclosure shown in FIG. 1 illustrating an exemplary transformer truck in an engaged position and an exemplary grounding switch mechanism in a non-grounded condition;

FIG. 3 is a front view of the transformer truck shown in FIG. 2 illustrating an exemplary arrangement of exemplary transformers;

FIG. 4 is a schematic side view of an exemplary fuse assembly that may be used with the transformers shown in FIG. 3;

FIG. 5 is a schematic side view of the transformer system shown in FIG. 2 illustrating the transformer truck in a disengaged position and the grounding switch mechanism in the non-grounded condition;

FIG. 6 is a partial side view of the grounding switch mechanism shown in FIG. 5;

FIG. 7 is a schematic side view of the transformer system shown in FIG. 2 illustrating the transformer truck in a disengaged position and the grounding switch mechanism in a grounded condition;

FIG. 8 is a partial side view of the grounding switch mechanism shown in FIG. 7; and

FIG. 9 is a flowchart of an exemplary method of disconnecting and grounding a transformer system.

Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of the disclosure. These features are believed to be applicable in a widc variety of systcms including one or more embodiments of the disclosure. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.

DETAILED DESCRIPTION

In the following specification and thc claims, reference will be made to a number of terms, which shall be defined to have the following meanings.

The singular forms “a” , “an” , and “the” include plural references unless the context clearly dictates otherwise.

“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about, ” “substantially, ” and “approximately, ” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.

Exemplary embodiments of transformer systems including transformer trucks are described herein. Transformer trucks are a type of electrical switchgcar within an electrical enclosure designed to transport transformers between an operational, engaged position and a service, disengaged position within the electrical enclosure. The transformer trucks described herein generally include a housing and a grounding switch. The housing is configured to receive a plurality of transformers arranged such that a first transformer of the plurality of transformers has a first orientatiou relative to a third direction and a laterally adjacent second transformer of the plurality of transformers has a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. The grounding switch mechanism has a non-grounded condition and a grounded condition and includes a pair of grounding arms coupled to inner portions of the housing that arc configured to rotate along a rotation direction between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms. In the example embodiment, the grounding switch mechanism is configured to de-energize the transformers when the grounding arms and the grounding bar are in the grounded condition and a door of a transformer system compartment has been opened. In one embodiment, the transformer truck includes a carrier extending along a first direction and the transformer truck is configured to translate along the carrier between an engaged position and a disengaged position while the transformer system compartment is closed. The transformer systems facilitate efficient space utilization within an electrical enclosure by using the vertically alternating arrangement of the transformers within the housing and enhanced electrical enclosure safety by facilitating de-energization of the transformers within the electrical enclosure without exposing an operator to the energized transformers.

FIG. 1 is a perspective and partial cutaway view of an exemplary embodiment of an electrical enclosure, for example electrical enclosure 100. A coordinate system 10 includes a first, horizontal X-axis, a second, lateral Y-axis, and a third, vertical Z-axis, the three axes orthogonal to each other. In the exemplary embodiment, electrical enclosure 100 includes at least one transformer compartment 102 and a breaker compartment 104. Each transformer compartment 102 includes at least one transformer compartment door 106 which allows access to an interior of electrical enclosure 100, for example to a transformer system 108 (shown in FIG. 2) . In the exemplary embodiment, transformer system 108 is configured to facilitate manipulation of electrical energy using a spatially-efficient arrangement of internal components while maintaining ease of maintenance and safety standards. More specifically, transformer system 108 includes a plurality of transformers 110 (shown in FIG. 2) , each transformer 110 coupled between a load side power line 105 and a line side power line 107 and configured to transfer electrical energy between two or more circuits through electromagnetic induction. In the exemplary embodiment, each transformer 110 is a voltage transformer 110 and varies current in a first internal coil of transformer 110 to produce a varying magnetic field to induce a second voltage in a second internal coil of transformer 110 and to increase or decrease an output voltage from the second internal coil. In an alternative embodiment, each transformer 110 is a current transformer 110. In other alternative embodiments, transformers 110 may be any type of transformer 110 or additional electrical component that facilitates operation of transformer system 108 as described herein.

Electrical enclosure 100 also includes a plurality of metal or metal-clad exterior panels 111 arranged upon and coupled to a plurality of supportive frame members 112, and which provide structural support and protection from conditions present in an exterual environment 114 outside electrical enclosure 100. Also, in the exemplary embodiment, the interior of electrical enclosure 100 includes a plurality of electrical components 116 such as electrical lines, switchgear, switches, connectors, and various other devices necessary to connect electrical load devices to main power lines, circuit breakers, and transformers, for example. Further, in the exemplary embodiment, the interior of electrical enclosure 100 includes one or more interior panels 118. Interior panel 118 may include one or more apertures 120 defined therethrough. Apertures 120 are configured to perform a number of functions in electrical enclosure 100 including, without limitation, to facilitate ventilation therein and permit connections between individual electrical components 116 of the plurality of electrical components 116 within electrical enclosure 100.

FIG. 2 is a schematic side view of an exemplary embodiment of a transformer system 108 that may bc used with electrical cnclosurc 100 (shown in FIG. 1) illustrating an exemplary transformer truck 200 in an engaged position 202 and an exemplary grounding switch mechanism 216 in a non-grounded condition 232. FIG. 3 is a front view of transformer truck 200 (shown in FIG. 2) illustratiug an cxcmplary arrangcmcnt of exemplary transformers 110. FIG. 4 is a schematic side view of an exemplary fuse assembly 204 that may be used with transformers 110 (shown in FIG. 3) . Transformer compartment door 106 is configured to rotate about a hinge 206 between an open position 208 (shown in FIG. 7) and a closed position 210. In alternative embodiments, transformer truck 200 may include any component that facilitates operation of transformer system 108 as described herein.

In the exemplary embodiment, transformer truck 200 includes a housing 212, a grounding system 214 including a grounding switch mechanism 216, and three transformers 110. In the exemplary embodiment, transformers 110 include a single fuse assembly 204 including a single fuse 218. Housing 212 is configured to receive transformers 110 oriented in an alternating arrangement with respect to the third direction. More specifically, a first transformer 110 of transformers 110 has a first orientation relative to the third direction and a laterally adjacent second transformer 110 of transformers 110 has a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. This orientation facilitates positioning three transfonners 110 within transformer truck 200 such that a first transformer 110 is positioned upright, a second transformer 110 is positioned upside-down and laterally adjacent to the first transformer 110, and a third transformer 110 is positioned upright and laterally adjacent to the second transformer 110, each fuse assembly 204 of the three transformers 110 positioned along a single lateral axis. In an alternative embodiment, transformers 110 may be arranged in any manner within housing 212 that facilitates operation of transformer system 108 as described herein.

In the exemplary embodiment, fuse assembly 204 includes a fuse housing 217, a fuse 218 positioned within fuse housing 217, a pin contact 220 positioned at a first end 222 of fuse housing 217, and a grounding switch contact 224 positioned at a second end 226 of fuse housing 217 opposite first end 222. In the exemplary embodiment, fuse 218 is a current-limiting medium voltage fuse 218. In alternative embodiments, fuse 218 may be any type of fuse 218 that facilitates operation of transformer 110 as described herein. Fuse housing 217 is configured to insulate fuse 218 from an outside environment, to retain pin contact 220 at first end 222 of fuse housing 217, and to retain grounding switch contact 224 at second end 226 of fuse housing 217. Pin contact 220 is configured to facilitate an electrical connection between line side power line 107 and fuse 218, and grounding switch contact 224 is configured to facilitate an electrical connection between fuse 218 and grounding system 214. In alternative embodiments, fuse assembly 204 may be configured in any manner that facilitates operation of transformer system 108 as described herein.

The vertically alternating arrangement of transformers 110 facilitates containing three transformers 110 within each housing 212 while meeting Institute of Electrical and Electronics Engineers (IEEE) compact switchgear standards. More specifically, transformer trucks 200 meeting IEEE compact switchgcar standards have an internal width 228 of six hundred fifty millimeters. Each transformer 110 has an external width of two hundred thirty five millimeters. Three transformers 110 positioned laterally adjacent to each other, and with the same orientations relative to the third direction, would have an overall width of seven hundred five millimeters (i.e., greater than internal width 228) , which would not allow three transformers to fit within a transformer truck meeting IEEE compact switchgear standards. Using the vertically alternating configuration disclosed herein facilitates receiving three transformers 110 within a transformer truck 200 that meets IEEE compact switchgear standards and that positions each fuse assembly 204 along a single lateral axis to facilitate use of a single grounding switch mechanism 216. In an alternative embodiment, transformer trucks 200 may be configured to receive any number of transformers 110 arranged in any manner that facilitates operation of transformer system 108 as described herein.

FIG. 5 is a schematic side view of transformer system 108 (shown in FIG. 2) illustrating transformer truck 200 in a disengaged position 230 and grounding switch mechanism 216 in non-grounded condition 232. FIG. 6 is a partial side view of grounding switch mechanism 216 (shown in FIG. 5) . FIG. 7 is a schematic side view of transformer system 108 (shown in FIG. 2) illustrating transformer truck 200 in a disengaged position 230 and grounding switch mechanism 216 in a grounded condition 234. FIG. 8 is a partial side view of grounding switch mechanism 216 (shown in FIG. 7) . In thc cxcmplary cmbodimcnt, with refcrencc to FIGS. 1-8, a carrier 240 is coupled between transformer compartment 102 and housing 212 and is configured to facilitate transformer truck 200 moving along the first direction between engaged position 202 and a disengaged position 230, wherein “engaged” means that pin contact 220 is in electrical contact with line side power line 107 and “disengaged” means that pin contact 220 is not in electrical contact with line side power linc 107. Grounding system 214 includes a grounding cable 236 that is electrically coupled between a grounding contact 238 proximate carrier 240 and grounding switch mechanism 216 and is configured to act as a ground for grounding switch mechanism 216. In alternative embodiments, transformer truck 200 may be configured in any manner that facilitates operation of transformer system 108 as described herein.

In the exemplary embodiment, grounding switch mechanism 216 includes a pair of grounding arms 242, a grounding bar 244, and a pair of grounding springs 246. Grounding arms 242 include a first grounding arm 248 coupled to a rotation shaft 250 coupled to an inner first wall 252 of housing 212 and a second grounding arm 254 coupled to another rotation shaft 250 coupled to an inner second wall 256 of housing 212 opposite inner first wall 252. Grounding bar 244 extends between distal portions 258 of first grounding arm 248 and second grounding arm 254. Distal portions 258 of first grounding arm 248 and second grounding arm 254 include grounding bar slots 260 extending slot lengths 262 along longitudinal axes 264 of first grounding arm 248 and second grounding arm 254. A pair of bar shafts 266 extend along the second direction from opposing ends of grounding bar 244 and are configured to engage respective grounding bar slots 260 of first grounding arm 248 and second grounding arm 254. First grounding arm 248 and second grounding arm 254 are configured to rotate along a rotation direction 268 about bar shafts 266 between grounded condition 234 and non-grounded condition 232. Grounding springs 246 are configured to exert a force on grounding arms 242 to cause grounding arms 242 to be biased towards non-grounded condition 232. In alternative embodiments, grounding switch mechanism 216 may include any components and bc configurcd in any manner that facilitates operation of transformer system 108 as described herein.

In the exemplary embodiment, housing 212 includes a first roiler channel 270 coupled to inner first wall 252 and a second roller channel 272 coupled to inner second wall 256. A first roller 274 is coupled to a second portion 276 of first grounding arm 248 and a second roller 278 is coupled to a second portion 276 of second grounding arm 254. First roller 274 is configured to be received by first roller channel 270 and second roller 278 is configured to be rcccivcd by second roller channel 272 to facilitate constraining grounding arms 242 throughout a range of travel along rotation direction 268 about grounding bar shafts 266 between grounded condition 234 and non-grounded condition 232. A push plate 280 is coupled to transformer compartment door 106 and is configured to retain grounding switch mechanism 216 in non-grounded condition 232 when transformer compartment door 106 is in closed position 210 and transformer truck 200 is in disengaged position 230. More specifically, push plate 280 is configured to cause grounding arms 242 to rotate along rotation direction 268 such that first roller 274 and second roller 278 are retained and/or received within a respective one of first roller channel 270 and second roller channel 272 when transformer truck 200 is in non-grounded condition 232 and transformer compartment door 106 is in closed position 210. In alternative embodiments, grounding arms 242 may be constrained in any manner during operation of transformer truck 200 that facilitates operation of transformer system 108 as described herein.

In the exemplary embodiment, housing 212 includes a first grounding bar channel 282 and a second grounding bar channel 284 configured to retain grounding bar 244 and to facilitate grounding bar 244 translating along the first direction. First grounding bar channel 282 is coupled to inner first wall 252 of housing 212 and second grounding bar channel 284 is coupled to inner second wall 256, laterally opposite inner first wall 252. First grounding bar channel 282 and sccond grounding bar channel 284 extend along the first dircction. Grounding switch mechanism 216 is configured such that, when transformer compartment door 106 is in closed position 210, grounding bar 244 is spaced apart from grounding switch contact 224 of fuse assembly 204 throughout the range of travel of transformer truck 200 from engaged position 202 to discngagcd position 230. As described herein, grounding switch mechanism 216 rotates along rotation direction 268 when transformer truck 200 is in disengaged position 230 and transformer compartment door 106 is in open position 208, causing grounding bar 244 to move along the first direction towards fuse assembly 204 until contact is made with grounding switch contact 224, de-energizing and/or grounding fuse 218 within fuse assembly 204.

In the exemplary embodiment, with reference to FIGS. 1-8, grounding switch mechanism 216 is retained in non-grounded condition 232 throughout the range of motion of transformer truck 200 within transformer compartment 102 while transformer compartment door 106 is in closed position 210, as described herein. Transformer system 108 facilitates improving user safety due to the ability to move transformer truck 200 from engaged position 202 to disengaged position 230 without opening transformer compartment door 106, isolating the user from electrical energy within transformer compartment 102. Opening transformer compartment door 106 while transformer truck 200 is in disengaged position 230 facilitates grounding switch mechanism 216 moving from grounded condition 234 to non-grounded condition 232, de-energizing and/or grounding transformers 110, as described herein.

FIG. 9 is a flowchart of an exemplary method 300 that may be used to de-energize and/or ground a transformer 110 using a transformer system 108 (shown in FIG. 2) . Referring to FIGS. 1-8, method 300 includes moving 302 transformer truck 200 along carrier 240 from engaged position 202 to disengaged position 230. Transformer truck 200 includes housing 212 and grounding switch mechanism 216. Housing 212 stores plurality of transformers 110 including a first transformer 110 having a first orientation relative to a third direction defined by transformer truck 200 and a laterally adjacent second transformer 110 having a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. Grounding switch mechanism 216 is switchable between non-grounded condition 232 and grounded condition 234, and includes pair of grounding arms 242 and grounding bar 244. Each of grounding arms 242 is coupled to respective tuner portions of housing 212 and is rotatable between non-grouuded condition 232 and grounded condition 234. Grounding bar 244 cxtcnds bctwccn pair of grounding arms 242. Method 300 also includes switching 304 grounding switch mechanism 216 from non-grounded condition 232 to grounded condition 234 to cause grounding bar 244 to contact grounding contacts 238 on plurality of transformers 110.

The embodiments described herein include transformer systems including transformer trucks. Transformer trucks are a type of electrical switchgear within an electrical enclosure designed to transport transformers between an operational, engaged position and a service, disengaged position within the electrical enclosure. The transformer trucks described herein generally include a housing and a grounding switch. The housing is configured to receive a plurality of transformers arranged such that a first transformer of the plurality of transformers has a first orientation relative to a third direction and a laterally adjacent sccond transformer of the plurality of transformers has a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation. The grounding switch mechanism has a non-grounded condition and a grounded condition and includes a pair of grounding arms coupled to inner portions of the housing that are configured to rotate along a rotation direction between the non-grounded condition and the grounded condition and a grounding bar extending between the pair of grounding arms. In the example embodiment, the grounding switch mechanism is configured to de-energize the transformers when the grounding arms and the grounding bar are in the grounded condition and a door of a transformer system compartment has been opened. In one embodiment, the transformer truck includes a carrier extending along a first direction and the transformer truck is configured to translate along the carrier between an engaged position and a disengaged position while the transformer system compartment door is closed. The transformer systems facilitate efficient space utilization within an electrical enclosure by using the vertically alternating arrangement of the transformers within the housing and enhanced electrical enclosure safety by facilitating de-energization and/or grounding of the transformers within the electrical enclosure without exposing an operator to the energized and/or non-grounded transformers.

An exemplary technical effect of the methods, systems, and apparatus described herein includes at least one of: a) improving electrical cnclosure internal space use efficiency, b) decreasing exposure of operators to energized electrical components, c) increasing effectiveness of grounding apparatus, and d) increasing reliability of transformer trucks.

Exemplary embodiments of transformer trucks and methods of using transformer trucks are described above in detail. The transformer trucks and methods are not limited to the specific embodiments described herein but, rather, components of the transformer trucks and/or operations of the methods may be utilized independently and separately from other components and/or operations described herein. Further, the described components and/or operations may also be defined in, or used in combination with, other systems, methods, and/or devices, and arc not limited to practice with only the transformer trucks and systems described herein.

The order of execution or performance of the operations in the embodiments of the disclosure illustrated and described herein is not essential, unless otherwise specified. That is, the operations may be performed in any order, unless otherwise specified, and embodiments of the disclosure may include additional or fewer operations than those disclosed herein. For example, it is contemplated that executing or performing a particular operation before, contemporaneously with, or after another operation is within the scope of aspects of the disclosure.

Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.

This written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

TRANSFORMER SYSTEMS INCLUDING TRANSFORMER TRUCKS PARTS LIST

10	Coordinate system
100	E1ectrical Enclosure
102	Transformer compartment
104	Breaker compartment
105	Load side power line
106	Transformer compartment door
107	Line side power 1ine
108	Transformer system
110	Transformer
111	Exterior panels
112	Supportive frame members
114	External environment
116	Electrical components
118	Interior panels
120	Apertures

200	Transformer truck

202	Engaged position
204	Fuse assembly
205	Load side power line
206	Hinge, compartment door
207	Line side power line
208	Open position
210	Closed position
212	Housing
214	Grounding system
216	Grounding switch mechanism
217	Housing, fuse
218	Fuse
220	Pin contact
222	First end, fuse assembly
224	Grounding switch contact
226	Second end
228	Internal width, transformer truck
230	Disengaged position, transformer truck
232	Non-grounded condition, grounding switch mechanism
234	Grounded condition, grounding switch mechanism

236	Grounding cable
238	Grounding contact
240	Carrier
242	Grounding arms, pair of
244	Grounding bar
246	Grounding springs
248	First grounding arm
250	Rotation shaft
252	First wall, inner
254	Second grounding arm
256	Second wall, inner
258	Distal portion
260	Grounding bar slots
262	Slot lengths
264	Longitudinal axis, rotation arm
266	Grounding bar shafts
268	Rotation direction
270	First Roller channel
272	Second roller channel
274	First roller

276	Second portion
278	Second roller
280	Push plate
282	First grounding bar channel
284	Second grounding bar channel

Claims

A transformer truck for a transformer system, said transformer truck defining a first direction, a second direction, and a third direction, the three directions orthogonal to each other, said transformer truck comprising:

a housing arranged to receive a first transformer, said first transformer in a first orientation relative to the third direction and a laterally adjacent second transformer in a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation; and

a grounding switch mechanism coupled to said housing and switchable between a non-grounded condition and a grounded condition, said grounding switch mechanism comprising:

a pair of grounding arms each coupled to respective inner portions of said housing and rotatable between the non-grounded condition and the grounded condition; and

a grounding bar extending bctwccn said pair of grounding arms.
The transformer truck of Claim 1, wherein said grounding bar extends along the second direction between said pair of grounding arms.
The transformer truck of Claim 1, wherein said housing comprises a first wall and an opposite second wall, and wherein said pair of grounding arms comprises a first arm coupled to an inner portion of said first wall and a second arm coupled to an inner portion of said second wall.
The transformer truck of Claim 1, wherein said grounding switch mechanism further comprises at least one spring coupled between at least one grounding arm of said pair of grounding arms and said housing, and wherein said at least one spring is operable to exert a force on said at least one grounding arm to cause said pair of grounding arms and said grounding bar to rotate.
The transformer truck of Claim 1 further comprising a carrier extending along the first direction and a grounding contact coupled to said carrier, wherein said housing is translatable along said carrier between an engaged position and a disengaged position, and wherein a grounding cable is coupled between said grounding contact and said grounding switch mechanism.
The transformer truck of Claim 2, wherein said housing comprises a first grounding bar channel and a second grounding bar channel that retain said grounding bar.
The transformer truck of Claim 1, wherein said housing comprises a first roller channel and a second roller channel.
The transformer truck of Claim 7, wherein said pair of grounding arms comprises a first grounding arm comprising a first roller and a second grounding arm comprising a second roller, said first roller and said second roller engaging said first roller channel and said second roller channel, respectively.
A transformer system for an electrical enclosure, the electrical enclosure defining a first direction, a second direction, and a third direction, the three directions orthogonal to each other, said transformer system comprising:

a transformer truck coupleable between a load side power line coupled to at least one electrical component and a line side power line coupled to at least one electrical power source, said transformer truck comprising:

a housing;

a plurality of transformers arranged within said housing, wherein a first transformer of said plurality of transformers has a first orientation relative to the third direction, and wherein a laterally adjacent second transformer of said plurality of transformers has a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation; and

a grounding switch mechanism coupled to said housing and switchable between a non-grounded condition and a grounded condition, said grounding switch mechanism comprising:

a pair of grounding arms coupled to inner portions of said housing and configured to rotate along a rotation direction between the non-grounded condition and the grounded condition; and

a grounding bar extending between said pair of grounding arms.
The transformer system of Claim 9, wherein each transformer of said plurality of transformers comprises one of a voltage transformer and a current transformcr.
The transformer system of Claim 9, wherein said grounding bar extends along the second direction between said pair of grounding arms.
The transformer systcm of Claim 9, whcrein said housing comprises a first wall and an opposite second wall, and wherein said pair of grounding arms comprises a first arm coupled to an inner portion of said first wall and a second arm coupled to an inner portion of said second wall.
The transformer system of Claim 9, wherein said grounding switch mechanism further comprises at least one spring coupled between at least one grounding arm of said pair of grounding arms and said housing, and wherein said at least one spring is opcrablc to cxcrt a forcc on said at least one grounding arm to cause said pair of grounding arms and said grounding bar to rotate.
The transformer system of Claim 9, wherein each transformer of said plurality of transformers comprises a fuse assembly, each fuse assembly comprising:

a fuse housing;

a fuse positioned with said fuse housing;

a pin contact positioned at a first end of said fuse housing; and

a grounding switch contact positioned at a second end of said fuse housing, said second end opposite said first end.
The transformer system of Claim 13 further comprising a carrier extending along the first direction, wherein said transformer truck translatable along said carrier between an engaged position and a disengaged position.
The transformer system of Claim 15 further comprising a grounding contact coupled to said carrier and a grounding cable coupled between said grounding contact and said grounding switch mechanism.
The transformcr system of Claim 11, wherein said housing further comprises a first grounding bar channel and a second grounding bar channel that retain said grounding bar.
The transformer system of Claim 17, wherein said housing comprises a first roller channel and a second roller channel, and wherein said pair of grounding arms comprises a first grounding arm comprising a first roller and a second grounding arm comprising a second roller, said first roller and said second roller engaging said first roller channel and said second roller channel, respectively.
The transformer system of Claim 15, further comprising a push plate coupled to a transformer compartment door of the clcctrical cnclosurc, wherein said push plate is arranged to retain said grounding switch mechanism in a non-grounded condition when the transformer compartment door is in a closed position and said transformer truck is in the disengaged position.
A method of de-energizing a transformer, said method comprising:

moving a transformer truck along a carrier from an engaged position to a disengaged position, the transformer truck including:

a housing storing a plurality of transformers including a first transformer having a first orientation relative to a third direction defined by the transformer truck and a laterally adjacent second transformer having a second orientation relative to the third direction, wherein the second orientation is opposite to the first orientation; and

a grounding switch mechanism coupled to said housing and switchable between a non-grounded condition and a grounded condition, the grounding switch mechanism comprising:

a pair of grounding arms each coupled to respective inner portions of the housing and rotatable between the non-grounded condition and the grounded condition;

a grounding bar extending between the pair of grounding arms; and

switching the grounding switch mechanism from the non-grounded condition to the grounded condition to cause the grounding bar to contact grounding contacts on the plurality of transformers.