DRIVING SYSTEM FOR AN ON-LOAD TAP CHANGER
20240079190 ยท 2024-03-07
Inventors
- Borislav VASILEV (Sofia, BG)
- Georgi Manev (Sofia, BG)
- Veselin Nikolov (Sofia, BG)
- Angel Mihaylov (Plovdiv, BG)
Cpc classification
International classification
Abstract
The present disclosure relates to a driving system for an on-load tap changer, comprising a vacuum interrupter driving mechanism configured to drive a vacuum interrupter of the on-load tap changer, an energy accumulation mechanism mechanically coupled with the vacuum interrupter driving mechanism, and a flywheel mechanism mechanically coupled with the vacuum interrupter driving mechanism. The flywheel mechanism comprises a flywheel. The energy accumulation mechanism is mechanically coupled with a primary driving unit and is configured to accumulate and release energy for combined motion of the vacuum interrupter driving mechanism and the flywheel mechanism. The vacuum interrupter driving mechanism and the flywheel mechanism are arranged along a main driving axis and the flywheel is concentrically arranged around the main driving axis.
Claims
1. A driving system for an on-load tap changer, comprising: a vacuum interrupter driving mechanism configured to drive a vacuum interrupter of the on-load tap changer; an energy accumulation mechanism mechanically coupled with the vacuum interrupter driving mechanism; and a flywheel mechanism mechanically coupled with the vacuum interrupter driving mechanism, wherein the flywheel mechanism comprises a flywheel which is configured as annular rounded flywheel, such that there is a free space inside the annulus of the annular rounded flywheel, wherein the energy accumulation mechanism is mechanically coupled with a primary driving unit and the energy accumulation mechanism is configured to accumulate and release energy for combined motion of the vacuum interrupter driving mechanism and the flywheel mechanism, and wherein the vacuum interrupter driving mechanism and the flywheel mechanism are arranged along a main driving axis and the flywheel is concentrically arranged around the main driving axis.
2. The driving system according to claim 1, wherein the primary driving unit is mechanically coupled with a motor drive unit connection.
3. The driving system according to claim 1, wherein the energy accumulation mechanism comprises a spring mechanism configured to accumulate spring energy and a loading mechanism mechanically coupled with the primary driving unit and with the spring mechanism, wherein the loading mechanism is configured to load the spring mechanism for accumulating spring energy in the spring mechanism such that the accumulated spring energy is releasable from the loaded spring mechanism to drive the vacuum interrupter driving mechanism.
4. The driving system according to claim 1, wherein the vacuum interrupter driving mechanism comprises a rotary wheel arranged around the main driving axis and eccentrically coupled with a coupling element of the energy accumulation mechanism, wherein the coupling element of the energy accumulation mechanism is configured to transmit rotary motion caused by the release of energy from the energy accumulation mechanism into rotary motion of the rotary wheel of the vacuum interrupter driving mechanism.
5. The driving system according to claim 1, further comprising a selector system driving mechanism configured to drive a selector system of the on-load tap changer, wherein the selector system driving mechanism is mechanically coupleable with a drive shaft of the selector system for driving the selector system, and wherein the selector system driving mechanism is mechanically coupleable with the primary driving unit.
6. The driving system according to claim 5, wherein the selector system driving mechanism comprises a coupling configured to transmit rotary movement from the primary driving unit to the selector system driving mechanism in determined rotary states of the primary driving unit and to cause an idle movement of the primary driving unit with respect to the selector system driving mechanism in other rotary states of the primary driving unit.
7. The driving system according to claim 1, further comprising a changeover selector driving mechanism configured to drive a changeover selector of the on-load tap changer, wherein the changeover selector driving mechanism is mechanically coupleable with a drive shaft of the changeover selector for driving the changeover selector, and wherein the changeover selector driving mechanism is mechanically coupled with the primary driving unit.
8. The driving system according to claim 7, wherein the selector system driving mechanism comprises a driving wheel, wherein the driving wheel is mechanically coupleable with the primary driving unit and with a rotary element, such that the rotary element is rotatable by the primary driving unit via the driving wheel, and wherein the changeover selector driving mechanism is mechanically coupled with the rotary element, such that the rotary element is rotatable by the driving wheel of the selector system driving mechanism and the changeover selector driving mechanism is operable by the rotary element.
9. An on-load tap changer, comprising a driving system comprising: a vacuum interrupter driving mechanism configured to drive a vacuum interrupter of the on-load tap changer; an energy accumulation mechanism mechanically coupled with the vacuum interrupter driving mechanism; and a flywheel mechanism mechanically coupled with the vacuum interrupter driving mechanism, wherein the flywheel mechanism comprises a flywheel which is configured as annular rounded flywheel, such that there is a free space inside the annulus of the annular rounded flywheel, wherein the energy accumulation mechanism is mechanically coupled with a primary driving unit and the energy accumulation mechanism is configured to accumulate and release energy for combined motion of the vacuum interrupter driving mechanism and the flywheel mechanism, and wherein the vacuum interrupter driving mechanism and the flywheel mechanism are arranged along a main driving axis and the flywheel is concentrically arranged around the main driving axis.
10. The on-load tap changer according to claim 9, comprising a cylindrically formed housing and a carrying flange arranged on the cylindrically formed housing, wherein the driving system is attached to the carrying flange and concentrically placed relative to the cylindrically formed housing.
11. A method of operating a driving system for an on-load tap changer, the method comprising: mechanically coupling an energy accumulation mechanism of the driving system with a primary driving unit of the driving system to accumulate energy; mechanically coupling the energy accumulation mechanism with a vacuum interrupter driving mechanism of the driving system; mechanically coupling the vacuum interrupter driving mechanism with a flywheel mechanism, wherein the flywheel mechanism comprises a flywheel which is configured as annular rounded flywheel, such that there is a free space inside the annulus of the annular rounded flywheel, and wherein the vacuum interrupter driving mechanism and the flywheel mechanism are arranged along a main driving axis and the flywheel is concentrically arranged around the main driving axis; accumulating energy in the energy accumulation mechanism by loading the energy accumulation mechanism through operation of the primary driving unit; and releasing the accumulated energy from the energy accumulation mechanism for combined motion of the vacuum interrupter driving mechanism and the flywheel mechanism to drive a vacuum interrupter of the OLTC.
12. The method according to claim 11, applied to a driving system according to claim 1 or to an on-load tap changer according to claim 9 or 10.
13. The method according to claim 11, applied to an on-load tap changer according to claim 9.
14. The on-load tap changer according to claim 9, wherein the primary driving unit is mechanically coupled with a motor drive unit connection.
15. The on-load tap changer according to claim 9, wherein the energy accumulation mechanism comprises a spring mechanism configured to accumulate spring energy and a loading mechanism mechanically coupled with the primary driving unit and with the spring mechanism, wherein the loading mechanism is configured to load the spring mechanism for accumulating spring energy in the spring mechanism such that the accumulated spring energy is releasable from the loaded spring mechanism to drive the vacuum interrupter driving mechanism.
16. The on-load tap changer according to claim 9, wherein the vacuum interrupter driving mechanism comprises a rotary wheel arranged around the main driving axis and eccentrically coupled with a coupling element of the energy accumulation mechanism, wherein the coupling element of the energy accumulation mechanism is configured to transmit rotary motion caused by the release of energy from the energy accumulation mechanism into rotary motion of the rotary wheel of the vacuum interrupter driving mechanism.
17. The on-load tap changer according to claim 9, the driving system further comprising a selector system driving mechanism configured to drive a selector system of the on-load tap changer, wherein the selector system driving mechanism is mechanically coupleable with a drive shaft of the selector system for driving the selector system, and wherein the selector system driving mechanism is mechanically coupleable with the primary driving unit.
18. The on-load tap changer according to claim 17, wherein the selector system driving mechanism comprises a coupling configured to transmit rotary movement from the primary driving unit to the selector system driving mechanism in determined rotary states of the primary driving unit and to cause an idle movement of the primary driving unit with respect to the selector system driving mechanism in other rotary states of the primary driving unit.
19. The on-load tap changer according to claim 9, the driving system further comprising a changeover selector driving mechanism configured to drive a changeover selector of the on-load tap changer, wherein the changeover selector driving mechanism is mechanically coupleable with a drive shaft of the changeover selector for driving the changeover selector, and wherein the changeover selector driving mechanism is mechanically coupled with the primary driving unit.
20. The on-load tap changer according to claim 19, wherein the selector system driving mechanism comprises a driving wheel, wherein the driving wheel is mechanically coupleable with the primary driving unit and with a rotary element, such that the rotary element is rotatable by the primary driving unit via the driving wheel, and wherein the changeover selector driving mechanism is mechanically coupled with the rotary element, such that the rotary element is rotatable by the driving wheel of the selector system driving mechanism and the changeover selector driving mechanism is operable by the rotary element.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] The accompanying figures are included to provide a further understanding. In the figures, elements of the same structure and/or functionality may be referenced by the same reference signs. It is to be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
[0037]
[0038]
[0039]
[0040]
[0041]
[0042]
[0043]
DETAILED DESCRIPTION
[0044]
[0045] According to the embodiment illustrated in
[0046] For example, the vacuum interrupter provides for a controlled opening and closing of electrical contacts in vacuum to bypass electric switching currents during a tap changing operation of the OLTC. Switching of the vacuum interrupter can, for example, be performed by rotary motion introduced into the vacuum interrupter by means of the driving system 1.
[0047] For example, the selector system of the OLTC comprises electric contact elements for electrically contacting and switching between taps of the OLTC to change between different transformer ratios of a transformer controlled by the OLTC. Switching of the electric contact elements of the selector system between respective taps of the OLTC can, for example, be performed by rotary motion introduced into the selector system by means of the driving system 1.
[0048] For example, the changeover selector of the OLTC comprises one or more electric contact elements for electrically contacting a voltage line of a high voltage side of an energy supply network with respective taps of the OLTC, connected by means of the selector system. Switching of the electric contact elements of the changeover selector can, for example, be performed by rotary and/or linear motion introduced into the changeover selector by means of the driving system 1.
[0049]
[0050] Due to the stacked arrangement of the different sections A, B, C the driving system 1 can be constructed with a compact size, keeping the constructional space small. This also leads to an optimization of the dielectric field distribution within the OLTC housing 4 (see
[0051]
[0052] Section A of the driving system 1 is a so-called energy accumulation section and provides an energy accumulation mechanism 14. The energy accumulation mechanism 14 comprises a loading mechanism 6 and a spring mechanism 7. The loading mechanism 6 is mechanically coupled with a MDU connection 5. The spring mechanism 7 is mechanically coupled with the loading mechanism 6. Due to a driving motion introduced by the MDU connection 5, the loading mechanism 6 can load the spring mechanism 7 for accumulating spring energy in the spring mechanism 7. The accumulated spring energy is releasable from the loaded spring mechanism 7 to drive the vacuum interrupter driving mechanism 10 of section B of the driving system 1. Section B is called a first driving section.
[0053] The energy accumulation section A also comprises a position indicator 8 configured to indicate a respective tap position of a selector system of the OLTC. The position indicator 8 is mechanically coupled with the MDU connection 5 and can be driven through MDU connection 5. The MDU connection 5 is configured to be coupled with an MDU of the OLTC.
[0054] The first driving section B comprises, besides the already mentioned vacuum interrupter driving mechanism 10, also a changeover selector driving mechanism 9 configured to drive a changeover selector of the OLTC. In addition, the first driving section B also comprises a selector system driving mechanism 11 configured to drive a selector system of the OLTC.
[0055] The selector system driving mechanism 11 is configured to be mechanically coupled along the secondary driving axis L2 with a primary driving unit of the energy accumulation section A, as is explained in detail below. Moreover, the selector system driving mechanism 11 is further mechanically coupled with the changeover selector driving mechanism 9 such that the changeover selector driving mechanism 9 can be actuated by the selector system driving mechanism 11, as is explained in further detail below.
[0056] The third section C according to
[0057] The construction of the flywheel mechanism 12 of the second driving section C allows for an improved inertial mass distribution on the flywheel 13 leading to a good driving performance for a stable and reliable operation of driven components of the OLTC, like the vacuum interrupter driving mechanism 10. Moreover, since the flywheel 13 is constructed as an annular flywheel and concentrically arranged around the main driving axis L1, a space-saving construction of the driving system 1 can be further enhanced. The annular construction of the flywheel 13 also enables components like the selector system driving mechanism 11 or the changeover selector driving mechanism 9 to be, at least partially, accommodated inside the outer annular extension of the flywheel 13 with the annular flywheel 13 surrounding these components. This also leads to a further saving of constructional space. Moreover, since the flywheel 13 is constructed as an annular flywheel and concentrically arranged around the main driving axis L1, the flywheel 13 serves for an optimized dielectric field distribution within the OLTC.
[0058] In the following and with regard to
[0059]
[0060] A loading rod 18 is eccentrically arranged on the gear wheel 16 of the primary driving unit 15 and connects the primary driving unit 15 through the gear wheel 16 with a loading lever 19 of the loading mechanism 6 of the energy accumulation mechanism 14. The loading lever 19 provides an upper rolling-contact bearing 20 on one end. With the other end, the loading lever 19 is pivoted in a holding area 36 of the energy accumulation mechanism 14. Under the loading lever 19 with its upper rolling-contact bearing 20 a further rotary lever, so-called switching lever (not illustrated in
[0061] The spring mechanism provides a right lever 22 and a left lever 23 between which two springs 24 are arranged. Each of the springs 24 connects the right and left levers 22 and 23. The right and left levers 22 and 23 can be actuated by the loading lever 19 through the upper rolling-contact bearing 20 which can be brought into contact with either of the right and left lever 22 and 23 at respective contact areas.
[0062] The action of the energy accumulation mechanism 14 is as follows. In an assumed starting position, the switching lever (not illustrated in
[0063]
[0064] The vacuum interrupter driving mechanism 10 is mechanically coupled with the switching lever (see above explanations) of the energy accumulation mechanism 14 of
[0065] Since the flywheel mechanism 12 (see
[0066] As further illustrated in
[0067] The coupling 28 is configured as a circle segment to transmit rotary movement from the primary driving unit 15 to the selector system driving mechanism 11 in determined rotary states or rotary movement positions of the primary driving unit 15 and to cause an idle movement of the primary driving unit 15 with respect to the selector system driving mechanism 11 in other rotary states of the primary driving unit 15. For example, the circle segment of coupling 28 is configured to interact with a counter-segment of the primary driving unit 15 only in certain determined position to each other. This means that in determined rotary states or rotary movement positions, the circle segment of coupling 28 and the counter-segment of the primary driving unit 15 are either in force-coupling or out of force-coupling. In force-coupling, the selector system driving mechanism 11 is driven by the primary driving unit 15. Out of force-coupling, the selector system driving mechanism 11 is not driven by the primary driving unit 15, the latter being in an idle movement mode.
The driving wheel 27 of the selector system driving mechanism 11 provides a gear wheel 37 coupled with another gear wheel 38 to form a gearing. The gear wheel 38 is arranged in line with a drive shaft (not shown) of the selector system for driving the selector system. Hence, by rotational movement of the selector system driving mechanism 11 through coupling with the primary driving unit 15 at coupling 28, the gearing 37/38 is actuated to drive the selector system (not shown).
[0068] The drive shaft of the selector system is, for example, coupled through other mechanics (e.g., Geneva mechanism) with tap selector elements of a selector system of the OLTC, such that a rotary movement of the drive shaft of the selector system leads to a switching movement within the selector system of the OLTC. For example, with beginning rotary movement of the drive shaft of the selector system a closed electrical contact between contact elements of the selector system with respective taps of the OLTC can be opened and with continuous rotary movement the electric contact elements travel to another tap position of the OLTC and close respective electrical contacts with the other tap by reaching a defined position through further rotary movement of the drive shaft of the selector system.
[0069] Further regarding the selector system driving mechanism 11, protrusions 30 on the driving wheel 27 are configured to interact with indentations 31 of a Geneva ring 32 of a rotary element 29. Hence, a rotary motion of the driving wheel 27 can be selectively transmitted into a rotary motion of the Geneva ring 32. In this way, the driving wheel 27 causes a movement of the Geneva ring 32 of the rotary element 29 according to a predetermined transmission ratio and/or a predetermined movement sequence.
[0070] The rotary element 29 further provides another Geneva drive 33 on its outer circumference, as illustrated in
[0071] The first driving section B according to
[0072]
[0073]
[0074]
[0075] The gear wheel 16 of the primary driving unit 15 couples with coupling 28 (force-coupling or idle movement as explained above). Due to this, the driving wheel 27 of the selector system driving mechanism 11 is actuated and causes rotary movement of the drive shaft 44 of the selector system (see above explanations). Moreover, the driving wheel 27 of the selector system driving mechanism 11, when actuated, causes rotary movement of the rotary element 29 with Geneva ring 32 and Geneva drive 33 (as explained above). The Geneva drive 33 is coupled with coupling element 34, the latter forming a Geneva sector, such that coupling element 34 is urgent into rotary movement due to rotary movement of the Geneva drive 33.
[0076] In this way, the Geneva mechanism 33/34 is configured to transmit rotational movement onto the shaft 39 of the changeover selector driving mechanism 9. In this embodiment, a bevel gear wheel 40 is attached to the shaft 39 of the changeover selector driving mechanism 9. The bevel gear wheel 40 interacts with a second bevel gear wheel 41 and rotates the second bevel gear wheel 41 through rotation of the first bevel gear wheel 40. A lever 42 is coupled to the second bevel gear wheel 41 for transmission of rotation into linear movement along a shaft 43 of the changeover selector for operating the changeover selector.
[0077] The driving system 1 provides a good performance regarding the accumulation and synchronous release of energy to perform the required driving, while at the same time not to release too much energy leading to a damage of the components. The driving system 1 supplies the energy, respectively the specific motions, needed for driving the different driving components, i.e. the vacuum interrupter driving mechanism 10 as well as the selector driving mechanism 11 and change-over selector driving mechanism 9, in an un-interrupted and synchronous matter.
[0078] While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the figures and described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure defined by the appended claims.)
[0079] The embodiments shown in the
REFERENCE SIGNS
[0080] 1 driving system [0081] 2 carrying flange [0082] 3 screw connection [0083] 4 housing [0084] 5 MDU connection [0085] 6 loading mechanism [0086] 7 spring mechanism [0087] 8 position indicator [0088] 9 changeover selector driving mechanism [0089] 10 vacuum interrupter driving mechanism [0090] 11 selector system driving mechanism [0091] 12 flywheel mechanism [0092] 13 flywheel [0093] 14 energy accumulation mechanism [0094] 15 primary driving unit [0095] 16 gear wheel [0096] 17 gear [0097] 18 loading rod [0098] 19 loading lever [0099] 20 upper rolling-contact bearing [0100] 21 lower rolling-contact bearing [0101] 22 right lever [0102] 23 left lever [0103] 24 springs [0104] 25 rotary wheel [0105] 26 coupling [0106] 27 driving wheel [0107] 28 coupling [0108] 29 rotary element [0109] 30 protrusion [0110] 31 indentation [0111] 32 Geneva ring [0112] 33 Geneva drive [0113] 34 coupling element [0114] 35 buffer element [0115] 36 holding area [0116] 37 gear wheel [0117] 38 gear wheel [0118] 39 shaft [0119] 40 bevel gear wheel [0120] 41 bevel gear wheel [0121] 42 lever [0122] 43 drive shaft of changeover selector [0123] 44 drive shaft of selector system [0124] 15 [0125] A energy accumulation section [0126] B first driving section [0127] C second driving section [0128] L1 main driving axis [0129] L2 secondary driving axis