Container based by-pass module for electric power lines

Abstract

A by-pass module for power lines includes a container having a housing space, three reels rotatable around rotation axes and housed into the housing space, single phase link for each reel having a first end termination and a second end termination, each single phase link being wound on a respective reel for being unwound from the first end termination, a driving unit for each reel designed for rotating the reel in an unwinding direction allowing the relevant single phase link to be unwound from the reel, and in a winding direction allowing the relevant single phase link to be wound on the reel.

Claims

1. A by-pass module for an electric power line comprising: a container having a housing space; at least one reel rotatable around a rotation axis and mounted into the housing space of the container; a single phase link wound on the reel and comprising a cable length, a first end termination and a second end termination; and a driving unit for the reel designed for rotating the reel in an unwinding direction, and in a winding direction, wherein the driving unit engages at least one flange for rotating the reel around the rotation axis and further comprises at least one motorized roller contacting a rim of the flange.

2. The by-pass module according to claim 1, wherein three reels are mounted into the housing space, each reel bearing a single phase link and being rotatable around a relevant rotation axis by a relevant driving unit.

3. The by-pass module according to claim 2, wherein the driving unit is designed for operating on a respective reel independently from remaining driving units.

4. The by-pass module according to claim 1, wherein at least said second end termination of the single phase link is a prefabricated flexible termination.

5. The by-pass module according to claim 1, wherein the reel comprises a substantially cylindrical bearing surface on which the single phase link is wound, said bearing surface being delimited by substantially annular flanges extending away from said bearing surface.

6. The by-pass module according to claim 1, wherein a flange rests on said motorized roller and on an idle roller, the motorized roller and the idle roller being spaced apart for supporting said reel within said container.

7. The by-pass module according to claim 6, wherein said motorized roller and said idle roller are provided on a lug extending from a base wall of said container, each reel being supported within said container only through said flanges, each of which contacts a respective idle roller and a respective motorized roller.

8. The by-pass module according to claim 1, wherein each driving unit comprises an electric motor and a transmission cinematically connecting said electric motor with two of said motorized rollers, each of said motorized rollers engaging the rim of a respective flange of one reel.

9. The by-pass module according to claim 1, comprising a fitting kit designed for being mechanically and/or electrically connected to at least one of said first end termination and second end termination of each single phase link, said fitting kit being stored in a secondary housing space of said container.

10. The by-pass module according to claim 9, wherein said fitting kit comprises a surge arrester, a connecting rod designed for mechanically connecting said surge arrester to a termination and bearing elements for mechanically coupling said surge arrester to one or more support elements provided on a top wall of said container.

11. The by-pass module according to claim 1, wherein at least one of said end terminations is a prefabricated plug-in cable joint.

12. The by-pass module according to claim 1, wherein said container is designed to be transportable.

13. A method for operating a by-pass of an electric power line comprising: providing a by-pass module comprising a container having a housing space, at least one reel rotatable around a rotation axis and mounted into said housing space, one single phase link wound on the reel and comprising a cable length, a first end termination and a second end termination, and a driving unit designed for rotating the reel in an unwinding direction and in a winding direction, wherein the driving unit engages at least one flange for rotating the reel around the rotation axis and further comprises at least one motorized roller contacting a rim of the flange; disposing said container; moving at least one sidewall of the container for accessing said reels and operating said driving units for unwinding the single phase link; and electrically connecting each end termination of the single phase links to two points of the power line.

14. The method according to claim 13, comprising stably fixing surge arresters on a top wall of the container and connecting flexible terminations, prefabricated on said first or second end termination of each single phase link, to said surge arresters.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will be now described more fully hereinafter with reference to the accompanying drawings.

(2) FIG. 1 is a schematic perspective view of a by-pass module for power lines, according to the present invention.

(3) FIG. 2 is a schematic perspective view of some details of the by-pass module of FIG. 1.

(4) FIG. 3 is a schematic perspective view of the by-pass module of FIG. 1 in a possible operative condition.

DETAILED DESCRIPTION

(5) With reference to the annexed figures, reference 1 globally denotes a by-pass module for electric power lines in accordance with the present invention.

(6) The by-pass module 1 shown in the figures is an example for use on 145 kV lines and the relevant substations.

(7) The by-pass module 1 comprises a container 2 having a main housing space 3. The container 2 is conveniently made in the form of a rigid frame having the size of a freight container, as for example a LC-20 sized container, so that it can be transported on a trailer, or, alternatively it can itself be equipped with a plurality of wheels so as to form a trailer or semitrailer.

(8) The container 2 conveniently comprises a base wall 2a, a top wall 2b opposite to the base wall, two major sidewalls 2c and two minor sidewalls 2d connecting the base wall to the top wall. Such walls form a containment delimiting the main housing space 3.

(9) In the container 2, one of the major sidewalls 2c is movable for forming a side opening.

(10) In the preferred embodiment the container 2 presents a secondary housing space 4 preferably adjacent to the housing space 3. The secondary housing space 4 is physically separated from the housing space 3 by a dividing wall 2e (illustrated in FIG. 2) extending between two major sidewalls 2c and between the base wall 2a and the top wall 2b. The minor sidewall 2d in correspondence with the secondary housing space 4 is movable for forming a side opening, so allowing easier access to the secondary housing space 4.

(11) Three reels 5, one for each phase, are arranged within the main housing space 3 of the container 2. A single phase link 6 is wound on each reel 5. Each single phase link 6 comprises a first end termination 7a, a second end termination 7b (FIG. 3) arranged beneath the relevant cable length 7c when the latter is wound around th reel 5. The phase link 6 is unwound from the reel 5 starting from the first end termination 7a. Each phase link 6 is designed for being completely unwound from the respective reel 5, so that both the end terminations 7a, 7b can be directly reached. The first and second end terminations 7a, 7b are ready for being connected to respective electric devices of the power line by-pass. In the embodiment depicted in FIG. 1, the second end termination 7b is a flexible outdoor termination, suitable for connecting to a proximate overhead point of the power line. In case the other, distal, point of the power line to be bypassed is an overhead point, also the first end termination 7a of each single phase link 6 is a flexible outdoor termination (as in the embodiment of FIG. 1) or, alternatively, with a relevant joint suitable for being connected to a stand-alone outdoor termination. In case the distal point of the power line to be bypassed is a point on the ground (or underground), the first end termination 7a is a relevant ground (or underground) joint. In case both the points to be by-passed are points on the ground (or underground), both the end terminations of each single phase link 6 are equipped with relevant ground (or underground) joints. When at least one point of the power line to be bypassed is a point on the ground (or underground), one of the first end termination 7a and second end termination 7b of each single phase link 6 is a prefabricated cable joint, for example as described in U.S. Pat. No. 5,316,492 and commercially available under the trademark CLICK FIT® (for example the model CFJ-CFJX) sold by the Applicant.

(12) In order to allow an easy and correct connection of each of the three single phase link 6 to the power line, the module 1 further comprises a fitting kit 8 designed for being mechanically and/or electrically connected to at least one of the first end termination 7a and second end termination 7b of each single phase link 6. Conveniently, the fitting kit 8 is stored in the secondary housing space 4 of the container 2 for being promptly available when the module has to be configured in the operating position (FIG. 3). When one point of the power line to be bypassed is an overhead point, the fitting kit 8 can comprise, for each single phase link 6, accessories such as a surge arrester 8a, a connecting rod 8b and bearing elements 8c.

(13) The container 2 further comprises support elements 9 provided on the top wall 2b of the container and designed for holding the accessories of the fitting kit 8 in operative position (FIGS. 1 and 3).

(14) The reels 5 are arranged within the housing space and are rotating therein, so that each single phase link 6 can be unwound and wound by rotating the relative reel. As detailed in FIG. 2, preferably, each reel 5 has its rotation axis X parallel to the base wall 2a of the container 2 and parallel to the movable sidewall 2c of the container. Each reel 5 comprises two flanges 10, having a substantial annular shape, delimiting the overall size of the reel. One flange 10 is present at each lateral end of a cylindrical bearing surface 5a of each reel 5 on which the single phase link 6 is wound. The reels 5 are supported within the container 2 by the respective flanges 10, preferably by the respective flanges 10 only.

(15) Advantageously, the flanges 10 are interlocked with driving units 11. Preferably, the module comprises three driving unit 11 each respectively interlocked with the flanges 10 of a sole reel 5. Each driving unit 11 comprises an electric motor (not shown) designed to rotate a driving shaft 12 extending from the base wall 2a of the container 2 between two flanges 10 of the same reel.

(16) The driving shaft 12 is mechanically connected, for example through a driving belt, to a couple of rollers 13, so motorizing the rollers 13. A guard 12a covers the driving shaft 12 and the relevant driving belt. Each motorized roller 13 of a respective driving unit is rotating and supported by a lug 14 emerging from the base wall 2a of the container 2. The lug 14 also supports a rotating idle roller 15 spaced apart from the motorized roller 13 along the lug 14. Each flange 10 rests on one idle roller 15 and on one motorized roller 13, so that a circumferential rim 10a of the flange 10 directly contacts the two rollers 13, 15. Preferably, the rotation axes of the rollers 13, 15 are parallel to the rotation axis X of the reels 5. The motorized rollers 13 are electrically energized to rotate and transmit such rotation to the flanges 10 and, accordingly, the reel 5. To this end, the module 1 comprises a control panel (not shown) designed for actuating the electric motors. Preferably, the control panel comprises independent controllers for each electric motor, so that each motor can be operated independently from the others.

(17) As already said, the module 1 can be conveniently transported, or stocked, in the operation place for being configured in the operation condition. The module can provide a sufficiently long connection, for example 50 or 100 meters in case of 145 kV electric lines or up to 200-250 meters in case of electric lines of above 45-90 kV.

(18) As shown in FIG. 1, in operation, the movable sidewalls of the container are opened so allowing the access to the housing space housing the reels and to the further housing space housing the fitting devices.

(19) In case one point of the power line to be bypassed is an overhead point and the power line is an high voltage power line, the surge arresters and the bearing elements may be unlatched from the second housing space and mounted on the relative support elements on the top wall of the container, as illustrated in FIG. 3. For example, the support elements 9 are designed to engage with the bearing elements 8c which, in turn, are connectable to a base portion of the surge arresters 8a, so that the surge arresters can be firmly held upright above the top wall 2b of the container. Conveniently, the surge arresters 8a, the bearing elements 8c and the support elements 9 are fastened together through bolts and nuts or similar connecting means. The bearing elements 8c are also designed for supporting the outdoor terminations, so that the latter can be firmly held upright and parallel to the surge arresters 8a. Preferably, the bearing elements acting on the outdoor terminations 7b are also active on a portion of cable 6b for firmly holding the same in position (FIG. 3). The bearing elements 8c can have any shape suitable for performing the above cited function. The connecting rods 8b are designed to be mounted between the top end terminations of the surge arresters and the outdoor terminations, as illustrated in FIG. 3.

(20) Alternatively, in case both power points of the by-pass are ground (or underground) points or in case the power line is a very high voltage power line, the surge arresters and the bearing elements may be left into the container.

(21) Any case, each single phase link 6 is then unwound from the respective reel by operating the driving units. During these operations, one end termination, preferably the first end termination 7a, of each single phase link 6 is transported in the proximity of the distal point of the by-pass, the other end terminations 7b remaining in the nearness of the container 2. The end terminations 7a transported to the distal point of the by-pass can be electrically connected to the by-pass point through an outdoor termination supported by a pylon, or through a ground or underground electric junction or through a flexible pre-mounted outdoor termination (depending on the type of by-pass point and on the voltage of the power line).

(22) In case the point of the by-pass near to the container is a overhead point (of a high voltage power line), and thus the surge arrester and the bearing elements have been mounted on the top wall of the container, the flexible outdoor terminations of each second end termination 7b are mounted on the relevant bearing elements. Then the connecting rods are mounted between the top portions of the surge arresters and of the flexible outdoor terminations for mechanically and electrically joining the same. Alternatively, these end terminations 7b can be electrically connected to the by-pass point through outdoor terminations supported by relevant pylons, or through ground or underground electric junctions (depending on the type of by-pass point and on the voltage of the power line).

(23) In operation, the three single phase link 6 are preferably laid close each other and latched together in a trefoil arrangement, so forming a single cord, as illustrated in FIG. 3.

(24) Once these operations have ended, the by-pass module is ready to be electrically connected to the electric line to be by-passed.