Drive system for on-load tap changer and on-load tap changer assembly

Abstract

The utility model relates to a kind of drive system and on-load tap-changer assembly for on-load tap-changer, the purpose is to improve the operation safety of on-load tap-changer. Drive system (20) includes motor (22) and the transmission shaft assembly (21) with transmission shaft (23), the transmission shaft of transmission shaft assembly is directly or indirectly connected with on-load tap-changer (10), motor is used to drive the transmission shaft assembly, to realize the gear switching of on-load tap-changer, wherein, drive system includes mechanical stop device (25), the mechanical stop device is configured for: when transmission shaft assembly switches on-load tap-changer to first limit gear along first rotation direction, prevent transmission shaft assembly continue to rotate along first rotation direction;When transmission shaft assembly switches on-load tap-changer to second limit gear along second rotation direction opposite to first rotation direction, prevent transmission shaft assembly continue to rotate along second rotation direction.

Description

Technical Field

[0001] This application generally relates to the field of on-load tap changer technology, and in particular to a drive system and on-load tap changer assembly for an on-load tap changer. Background Technology

[0002] In power transmission and distribution systems, adjustable transformers, as core power equipment, bear the crucial task of adjusting the output voltage in real time according to changes in grid load and voltage fluctuations. Their operational stability directly determines the quality and safety of the power grid. Adjustable transformers primarily achieve voltage regulation by changing the turns ratio of their windings, and in this process, on-load tap changers (OLTCs) play an indispensable role. OLTCs can switch between taps while the transformer is operating under load, ensuring continuous and uninterrupted voltage regulation and preventing disruptions to industrial production and residential life due to power outages. They are widely used in transmission lines, substations, and large industrial enterprises.

[0003] The reliable operation of an on-load tap changer depends on its matching drive system and the transmission mechanism within the on-load tap changer that forms a transmission connection with the drive system. The drive system typically consists of components such as a motor, transmission mechanism, and control device. Its core function is to precisely drive the tap changer contacts according to control commands, thereby switching the taps and ultimately achieving the switching of the on-load tap changer or transformer tap position.

[0004] However, the existing drive system has significant drawbacks: when the on-load tap changer is already at its limit position (such as the highest or lowest), due to possible mis-sending of control signals, delayed feedback, or other faults, the motor may still receive control signals to continue switching to a higher or lower position. In this case, the motor will continue to rotate, attempting to drive the drive shaft assembly and the transmission mechanism of the on-load tap changer. However, since the on-load tap changer has reached its limit and cannot continue to move, this forced rotation will cause severe mechanical impact and damage to the internal components of the on-load tap changer (such as contacts, gears, insulation structures, etc.), leading to on-load tap changer failure and affecting the normal operation of the transformer. In more serious cases, component damage may cause short circuits, arcing, and other faults, potentially leading to a transformer explosion, causing significant property damage and safety hazards.

[0005] Therefore, how to design a protection structure that can effectively prevent on-load tap changers from continuing to operate after reaching their limit positions has become a technical problem that needs to be solved in existing drive systems for on-load tap changers. Utility Model Content

[0006] In view of the above-mentioned deficiencies in the prior art, the purpose of this application is to provide an improved drive system for on-load tap changers that improves the operational safety and reliability of on-load tap changers and transformers.

[0007] According to a first aspect of this application, a drive system for an on-load tap changer is provided. The drive system includes a motor and a drive shaft assembly having a drive shaft. The drive shaft of the drive shaft assembly is directly or indirectly connected to the on-load tap changer. The motor drives the drive shaft assembly to achieve position switching of the on-load tap changer. The drive system includes a mechanical stop device configured to: prevent the drive shaft assembly from continuing to rotate in the first rotation direction when the drive shaft assembly switches the on-load tap changer to a first limit position along a first rotation direction; and prevent the drive shaft assembly from continuing to rotate in the second rotation direction when the drive shaft assembly switches the on-load tap changer to a second limit position along a second rotation direction opposite to the first rotation direction.

[0008] The drive system of this application uses a mechanical stop device to forcibly stop the transmission shaft assembly in the corresponding rotation direction at the limit gear position through a purely mechanical structure. This effectively avoids damage to the on-load tap changer caused by unexpected rotation of the motor and ensures the normal operation of the transformer.

[0009] In some embodiments, the first limit position is the lowest position of the on-load tap changer and the second limit position is the highest position of the on-load tap changer. Alternatively, the first limit position is the highest position of the on-load tap changer and the second limit position is the lowest position of the on-load tap changer.

[0010] In some embodiments, the mechanical stop device includes a limiting mechanism and a cooperating limiting mechanism. The limiting mechanism is operatively connected to the drive shaft assembly, and the cooperating limiting mechanism is non-rotatably mounted on the drive shaft assembly. When the on-load tap changer is not in its extreme position, the limiting element of the limiting mechanism and the cooperating limiting element of the cooperating limiting mechanism remain separated. However, when the on-load tap changer is in its extreme position along any rotation direction, the limiting element of the limiting mechanism contacts the cooperating limiting element of the cooperating limiting mechanism to prevent the drive shaft assembly from continuing to rotate in that direction. On one hand, keeping the limiting element and the cooperating limiting element separated when in the non-extreme position avoids frictional contact during normal operation, reduces component wear, and extends the overall service life of the mechanical stop device. On the other hand, when in the extreme position, stopping is achieved through mechanical abutment, which, compared to electric braking, offers a faster response speed (no signal transmission and processing delay) and higher stopping reliability.

[0011] In some embodiments, a drive pin is provided on one axial end face of the drive shaft assembly. The drive shaft assembly is operatively connected to a limiting mechanism via the drive pin, allowing the limiting element of the limiting mechanism to rotate about a rotation axis parallel to the rotation axis of the drive shaft assembly. This parallel axis design ensures precise and unbiased power transmission from the drive pin to the limiting mechanism, thereby guaranteeing accurate contact between the limiting element and the mating limiting element at the limit position, improving the accuracy of the stopping action.

[0012] In some embodiments, the limiting mechanism includes a first shaft assembly and a second shaft assembly, and the rotation axes of the first shaft assembly, the second shaft assembly, and the drive shaft assembly are all parallel. The first shaft assembly includes a first fixed shaft, a Maltese wheel, a first gear, and a second transmission element. The Maltese wheel and the second transmission element are rotatably supported on the first fixed shaft. The first gear is fixedly mounted or integrally formed on the side of the Maltese wheel facing the second transmission element. The first gear and the second transmission element are spaced apart along the axial direction of the first fixed shaft. The second shaft assembly includes a second fixed shaft, a second gear, and a first transmission element. The second gear and the first transmission element are rotatably supported on the second fixed shaft. A first pin element and a second pin element are provided on the side of the second gear facing the first transmission element. The first transmission element and the second gear are spaced apart along the axial direction of the second fixed shaft. The drive pin of the drive shaft assembly is used for operative connection with the Maltese wheel of the first shaft assembly. The first gear of the first shaft assembly meshes with the second gear of the second shaft assembly. Both the first pin element and the second pin element are used for operative connection with the first transmission element. The first transmission element is operatively connected to the second transmission element, and the second transmission element is configured as the limiting element. This design enables a simple way to convert the rotation of the drive shaft assembly into a precise stopping action of the second transmission element (limiting element).

[0013] In some embodiments, the first transmission element includes a radially extending section comprising a connecting region and an abutting region. The abutting region is closer to the second gear than the connecting region, and the distance between the abutting region and the second gear is less than the length of the first pin element and the second pin element extending from the second gear. The connecting region is configured with a receiving recess. The second transmission element includes an action connecting section comprising a first contact piece and a second contact piece. The first and second contact pieces are spaced apart and connected by a connecting rod. The connecting rod extends perpendicularly to the second fixed axis and passes through the receiving recess of the first transmission element. A first spring element and a second spring element are sleeved on the connecting rod. The first spring element is disposed between the first contact piece of the second transmission element and the connecting region of the first transmission element, and the second spring element is disposed between the second contact piece of the second transmission element and the connecting region of the first transmission element. The spacing design between the abutting region and the second gear ensures reliable contact between the pin element and the abutting region, avoiding transmission failure due to excessive spacing and guaranteeing the driving reliability of the first transmission element. The bidirectional buffering effect of the spring element effectively absorbs the impact load between the first and second transmission elements, avoiding component damage caused by rigid contact and extending the service life of the first and second transmission elements. Furthermore, in the non-stopping state, the restoring force of the spring element ensures that the second transmission element quickly returns to its initial position, preventing subsequent stopping actions from failing due to component jamming. Simultaneously, the reset process requires no additional power, simplifying the structural design and reducing energy consumption.

[0014] In some embodiments, the drive shaft assembly includes a dial non-rotatably supported on the drive shaft, the dial having a cylindrical pin on its axial end face, the cylindrical pin being configured as the drive pin, and a limiting mechanism having a Maltese wheel. The dial and the Maltese wheel cooperate as a Geneva mechanism. The movement of the Geneva mechanism has a strict angular correspondence, and by designing the number of grooves in the Geneva and the position of the cylindrical pin on the dial, the number of on-load tap changer positions and the extreme position can be precisely matched, thereby ensuring the accuracy of the stop action triggering timing.

[0015] In some embodiments, when the on-load tap changer is in the first extreme position along the first rotation direction, the first pin element of the second shaft assembly acts on the first transmission element and drives the first transmission element to rotate along the first rotation direction. The first transmission element further acts on the second transmission element and drives the second transmission element to rotate along the second rotation direction. Finally, the second transmission element contacts the mating limit element of the transmission shaft assembly to prevent the transmission shaft assembly from continuing to rotate along the first rotation direction. When the on-load tap changer is in the second extreme position along the second rotation direction, the second pin element of the second shaft assembly acts on the first transmission element and drives the first transmission element to rotate along the second rotation direction. The first transmission element further acts on the second transmission element and drives the second transmission element to rotate along the first rotation direction. Finally, the second transmission element contacts the mating limit element of the transmission shaft assembly to prevent the transmission shaft assembly from continuing to rotate along the second rotation direction.

[0016] In some embodiments, the engagement limiting mechanism of the drive shaft assembly is configured as a stop ring, which is non-rotatably mounted on the drive shaft. The outer circumferential surface of the stop ring includes a first circumferential segment and a second circumferential segment with different diameters. A first groove and a second groove are provided at the transition between the first circumferential segment and the second circumferential segment. The first groove is configured as a first engagement stop portion, and the second groove is configured as a second engagement stop portion. The second transmission element includes a first stop segment and a second stop segment; the first stop segment is configured with a first stop portion, and the second stop segment is configured with a second stop portion; the functional connecting segment, the first stop segment, and the second stop segment extend radially from the central segment of the second transmission element and are spaced apart along the circumferential direction. When the second transmission element rotates in the second rotation direction, the first stop portion can at least partially extend into the first groove of the mating limiting element to prevent the transmission shaft assembly from rotating in the first rotation direction; and when the second transmission element rotates in the first rotation direction, the second stop portion can at least partially extend into the second groove of the mating limiting element to prevent the transmission shaft assembly from rotating in the second rotation direction.

[0017] According to a second aspect of this application, an on-load tap changer assembly is provided, the on-load tap changer assembly including an on-load tap changer and a drive system for the on-load tap changer. The drive system is configured as a drive system for an on-load tap changer according to some embodiments of this application. Attached Figure Description

[0018] The present application will now be described in more detail with reference to the accompanying drawings and specific embodiments. The schematic drawings are briefly described below:

[0019] Figure 1 A simplified schematic diagram of an on-load tap changer assembly according to some embodiments of this application is shown;

[0020] Figures 2 to 7 Exemplary embodiments of a mechanical stop device for a drive system of an on-load tap changer according to this application are shown; and

[0021] Figures 8 to 10 The example illustrates the working process in a mechanical stop device where each pin element acts on a first transmission element and subsequently drives the first transmission element to act on a second transmission element. Detailed Implementation

[0022] The concept of this utility model will be further described in detail below with reference to specific embodiments. It should be noted that the embodiments listed herein are merely for clearly illustrating the concept of this utility model and should not be construed as limiting the present utility model. The technical features of the drive system for on-load tap changers involved in different embodiments can be arbitrarily combined or substituted within the scope of the concept of this utility model, as long as this is technically feasible.

[0023] In this document, the terms "illustrative" or "exemplary" mean "serving as an example, instance, or illustration." Any implementation described herein by example is not necessarily to be construed as preferred or advantageous over other implementations. Moreover, this application is not limited to any stated or implied theory given in the foregoing technical field, background art, utility model content, or specific embodiments.

[0024] In this paper, the term "functional connection" refers to a functional association established between two or more mechanical elements through a specific mechanical structure, component, or interface, which enables the motion or force of one mechanical element to be transmitted to another mechanical element.

[0025] Furthermore, the terms "first," "second," etc., used in this article are for reference only and do not have a limiting meaning. For example, unless the context clearly indicates otherwise, the words "first," "second," and other such numerical terms involving structures or elements do not imply order or sequence.

[0026] Figure 1 A simplified schematic diagram of an on-load tap changer assembly 100 according to some embodiments of this application is shown.

[0027] The on-load tap changer assembly 100 may include an on-load tap changer 10 and a drive system 20 for the on-load tap changer 10.

[0028] The drive system 20 may include a motor 22, a drive shaft assembly 21, and a control device 24. The motor 22 can drive the drive shaft assembly 21 via a motor shaft and optionally via a transmission mechanism. The drive shaft assembly 21 may include, for example, a drive shaft 23 and other mechanisms optionally formed or attached to the drive shaft. The drive system 20 may be directly or indirectly connected to the on-load tap changer 10, more specifically, to a transmission mechanism within the on-load tap changer 10, for example, via the drive shaft 23 of the drive shaft assembly 21. The control device 24 of the drive system 20 may include a control unit and a power unit (e.g., a converter), the control unit of which may, for example, operate the power unit via a bus to control the operation of the motor 22.

[0029] The on-load tap changer 10 may include a selector, an on-load switcher, and an optional preselector. In order to drive the on-load tap changer 10 to switch positions, the drive shaft assembly 21 or drive shaft 23 of the drive system 20 may act directly or indirectly on the on-load tap changer 10, i.e., on the selector and / or on-load switcher and / or preselector, so as to switch the on-load tap changer from the current tap position to the target tap position.

[0030] When the on-load tap changer 10 is already at its limit position (such as the highest or lowest position), due to possible mis-sending of the control signal, delayed feedback, or other faults, the motor 22 may still receive an erroneous control signal to "continue switching to a higher or lower position." In this case, the motor 22 will continue to rotate, attempting to forcefully drive the drive shaft assembly 21 and the transmission mechanism of the on-load tap changer 10. This process will generate a strong mechanical impact on the internal components of the on-load tap changer, easily leading to component damage and seriously affecting the reliability and service life of the equipment.

[0031] In order to solve the problem of component damage caused by the forced drive of the motor in the limit position of the on-load tap changer 10, this application provides a mechanical stop device 25 in the drive system 20, which realizes the forced stop of the transmission shaft assembly 21 in a specific rotation direction in the limit position through a purely mechanical structure.

[0032] The mechanical stop device 25 can be configured to: prevent the drive shaft assembly 21 from continuing to rotate in the first rotation direction when the on-load tap changer 10 is switched to the first extreme position (e.g., the lowest position) along the first rotation direction; and prevent the drive shaft assembly 21 from continuing to rotate in the second rotation direction when the on-load tap changer 10 is switched to the second extreme position (e.g., the highest position) along the second rotation direction opposite to the first rotation direction. Through this design, the mechanical stop device 25 can automatically cut off the rotation path of the drive shaft assembly along the corresponding rotation direction when the on-load tap changer is in the highest or lowest position, thereby avoiding damage to the on-load tap changer components caused by forced rotation of the motor.

[0033] The first extreme position can be the lowest position of the on-load tap changer, and the second extreme position can be the highest position of the on-load tap changer. Alternatively, the first extreme position can be the highest position of the on-load tap changer, and the second extreme position can be the lowest position of the on-load tap changer.

[0034] The first rotation direction can be set to clockwise and the second rotation direction can be set to counterclockwise. Alternatively, the first rotation direction can be counterclockwise and the second rotation direction can be clockwise.

[0035] Figures 2 to 7 Some exemplary embodiments of the mechanical stop device 25 for a drive system of an on-load tap changer are shown.

[0036] like Figure 1 As can be seen, the mechanical stop device 25 may include a limiting mechanism 30 and a cooperating limiting mechanism 60. The limiting mechanism 30 is operatively connected to the drive shaft assembly 21, and the cooperating limiting mechanism 60 (e.g., via a key connection, interference fit, etc.) is non-rotatably mounted on the drive shaft assembly 21. When the on-load tap changer 10 is not in its extreme position, the limiting element 27 of the limiting mechanism 30 and the cooperating limiting element 28 of the cooperating limiting mechanism 60 remain separated, thus not affecting the normal rotation of the drive shaft assembly 21. However, when the on-load tap changer 10 is in its extreme position along any rotation direction, the limiting element 27 of the limiting mechanism 30 and the cooperating limiting element 28 of the cooperating limiting mechanism 60 come into contact, thereby preventing the drive shaft assembly 21 from continuing to rotate in that rotation direction through mechanical abutment.

[0037] In order to achieve stable motion transmission from the drive shaft assembly 21 to the limiting mechanism 30, a drive pin 26 is provided on one axial end face of the drive shaft assembly 21. The drive shaft assembly 21 is operatively connected to the limiting mechanism 30 through the drive pin 26, so that the limiting element 27 of the limiting mechanism 30 can rotate around a second rotation axis parallel to the first rotation axis of the drive shaft assembly 21.

[0038] According to a preferred embodiment, the drive shaft assembly 21 can achieve transmission via a Geneva mechanism consisting of a dial and a Maltese wheel, and a limiting mechanism 30. Specifically, the drive shaft assembly 21 may include a dial 36 that is non-rotatably supported on the drive shaft 23 (e.g., by a key connection). The dial 36 has a cylindrical pin on its axial end face, which is the aforementioned drive pin 26. Furthermore, the outer peripheral surface of the dial 36 may be provided with a continuous circumferential convex arc surface.

[0039] The limiting mechanism 30 has a Maltese wheel 34, which is constructed as a grooved wheel with radial grooves 29. In this embodiment, the Maltese wheel 34 has six radial grooves 29. However, the number of radial grooves 29 can be flexibly designed according to the on-load tap changer's position requirements (e.g., four, five, eight, ten, twelve, etc.). The outer circumferential surface of the Maltese wheel is provided with multiple evenly spaced circumferential concave arc surfaces, and the number of circumferential concave arc surfaces is consistent with the number of radial grooves 29.

[0040] The working process of the Geneva mechanism is as follows:

[0041] When the dial 36 rotates continuously with the drive shaft 23, the drive pin 26 on the dial will enter a radial groove 29 of the Malt wheel 34, causing the Malt wheel 34 to rotate synchronously. When the dial 36 rotates through a specific angle (which is determined by the number of radial grooves) and the drive pin 26 exits the radial groove 29, the circumferential concave arc surface of the Malt wheel 34 is in contact with the circumferential convex arc surface of the dial 36, at which point the Malt wheel 34 remains stationary. This process is repeated until the drive pin 26 enters the next radial groove 29, ultimately converting the continuous rotation of the dial 36 into the intermittent rotation of the Malt wheel 34.

[0042] According to one embodiment, the limiting mechanism 30 may include a first shaft assembly 31 and a second shaft assembly 32, and the rotation axes of the first shaft assembly 31 and the second shaft assembly 32 are both parallel to the rotation axis of the transmission shaft assembly 21.

[0043] According to some embodiments, such as combining Figure 3 and Figure 4 The first shaft assembly 31 may include a first fixed shaft 33, a Maltese wheel 34, a first gear 35, and a second transmission element 40. For clarity, in... Figure 3 The second transmission element 40 is hidden in the middle. Figure 4The Maltese wheel 34 and the first gear 35 are hidden in the middle.

[0044] The Maltese wheel 34 and the second transmission element 40 are rotatably supported on the first fixed shaft 33, for example, by bearings. The first gear 35 is fixedly mounted or integrally formed on the side of the Maltese wheel 34 facing the second transmission element 40. The first gear 35 and the second transmission element 40 are spaced apart along the axial direction of the first fixed shaft 33 to avoid motion interference.

[0045] According to some embodiments, such as combining Figure 4 and Figure 5 The second shaft assembly 32 may include a second fixed shaft 37, a second gear 38, and a first transmission element 39. The second gear 38 and the first transmission element 39 are rotatably supported on the second fixed shaft 37, for example, by bearings. A first pin element 41 and a second pin element 42 are provided on the side of the second gear 38 facing the first transmission element 39, and these two pin elements are spaced apart along the circumferential direction of the second gear 38. The first transmission element 39 and the second gear 38 are spaced apart along the axial direction of the second fixed shaft 37 to avoid motion interference. The first gear 35 of the first shaft assembly 31 meshes with the second gear 38 of the second shaft assembly 32 to form a gear transmission pair, transmitting the intermittent rotation of the Maltese wheel 34 to the second gear 38, thereby driving the second gear 38 to rotate synchronously and intermittently. Preferably, the transmission ratio between the first gear 35 and the second gear 38 is greater than 1, preferably greater than 5, achieving more precise rotation control of the limiting mechanism 30 through speed reduction transmission, thereby ensuring accurate triggering of the limiting action. The first fixed shaft 33 and the second fixed shaft 37 may be supported, for example, on the housing of the drive system and / or the housing of the on-load tap changer.

[0046] The first pin element 41 and the second pin element 42 are both used to connect with the first transmission element 39. The first transmission element 39 and the second transmission element 40 are connected to each other. The second transmission element 40 is configured as the limiting element 27.

[0047] When the on-load tap changer 10 is in the first limit position along the first rotation direction, the first pin element 41 of the second shaft assembly 32 acts on (contacts) the first transmission element 39 and drives the first transmission element 39 to rotate along the first rotation direction. The first transmission element 39 further acts on the second transmission element 40 and drives the second transmission element 40 to rotate along the second rotation direction. Finally, the first stop part 43 of the second transmission element 40 contacts the first stop part 44 of the engagement limit element 28 of the transmission shaft assembly to prevent the transmission shaft assembly 21 from continuing to rotate along the first rotation direction.

[0048] When the on-load tap changer 10 is in the second limit position along the second rotation direction, the second pin element 42 of the second shaft assembly 32 acts on (contacts) the first transmission element 39 and drives the first transmission element 39 to rotate along the second rotation direction. The first transmission element 39 further acts on the second transmission element 40 and drives the second transmission element 40 to rotate along the first rotation direction. Finally, the second stop portion 45 of the second transmission element 40 contacts the second stop portion 46 of the engagement limit element 28 of the transmission shaft assembly 21 to prevent the transmission shaft assembly 21 from continuing to rotate along the second rotation direction.

[0049] According to some embodiments, such as combining Figure 3 and Figure 5 The engagement limiting mechanism 60 of the drive shaft assembly 21 can be configured as a stop ring 47, which is mounted on the drive shaft 23 in a non-rotatable manner (such as a keyed connection or interference fit). The outer circumferential surface of the stop ring 47 includes a first circumferential segment 48 and a second circumferential segment 49 with different diameters, wherein the diameter of the first circumferential segment 48 is larger than the diameter of the second circumferential segment 49. A first groove 54 and a second groove 55 are provided at the transition between the first and second circumferential segments, wherein the first groove 54 is configured as the aforementioned first engagement stop portion 44 and the second groove 55 is configured as the aforementioned second engagement stop portion 46, for engaging with the corresponding stop portion of the second transmission element 40.

[0050] According to some embodiments, such as combining Figure 3 and Figure 5 The first transmission element 39 includes a radially extending section 56, which includes a connecting region 57 and an abutting region 58. Along the axial direction of the second fixed shaft 37, the abutting region 58 is closer to the second gear 38 than the connecting region 57, and the distance between the abutting region 58 and the second gear 38 is less than the length of the first pin element 41 and the second pin element 42 extending out of the second gear 38, preferably less than half the extension length, to ensure that each pin element can effectively contact the abutting region 58. Additionally, the connecting region 57 is configured with a receiving recess 59.

[0051] According to some embodiments, such as combining Figure 5 and Figure 6The second transmission element 40 includes an operational connection section 50, which includes a first contact piece 61 and a second contact piece 62. The first contact piece 61 and the second contact piece 62 are spaced apart and connected by a connecting rod 63. The connecting rod 63 extends perpendicularly to the second fixed shaft 37 and passes through the receiving recess 59 of the connection area 57 of the first transmission element 39. A first spring element 64 and a second spring element 65 are sleeved on the connecting rod 63. The first spring element 64 is disposed between the first contact piece 61 of the second transmission element 40 and the connection area 57 of the first transmission element 39, and the second spring element 65 is disposed between the second contact piece 62 of the second transmission element 40 and the connection area 57 of the first transmission element 39. When the first transmission element 39 drives the second transmission element 40 to rotate, the spring element can buffer the instantaneous impact force; when the on-load tap changer exits the limit position, the spring element can drive the second transmission element 40 to reset to the initial position, ensuring that subsequent gear switching proceeds normally. According to a preferred embodiment, a washer is provided between the connection region 57 of the first transmission element 39 and each spring element, thereby ensuring that the first transmission element 39 applies more uniform pressure to the spring elements. The first spring element 64 and the second spring element 65 may be configured as compression springs, for example.

[0052] According to some embodiments, see, for example Figure 5 The second transmission element 40 may further include a first stop section 51 and a second stop section 52. The functional connection section 50, the first stop section 51, and the second stop section 52 extend radially from the central section 53 of the second transmission element 40 and are spaced apart in the circumferential direction to ensure that the functional parts do not interfere with each other. The first stop section 51 is constructed with the aforementioned first stop portion 43, and the second stop section 52 is constructed with the aforementioned second stop portion 45.

[0053] When the second transmission element 40 rotates in the second rotation direction, the first stop section 51 can extend at least partially into the first groove 54 of the mating limiting element 28 to prevent the transmission shaft assembly 21 from rotating in the first rotation direction and to achieve the stop of the first limit position; and when the second transmission element rotates in the first rotation direction, the second stop section 52 can extend at least partially into the second groove 55 of the mating limiting element 28 to prevent the transmission shaft assembly 21 from rotating in the second rotation direction and to achieve the stop of the second limit position.

[0054] According to one embodiment, such as Figure 7 As indicated by the digital scale on the second gear 38, the on-load tap changer 10 can have nine switching positions, with the lowest position being position 1 and the highest position being position 9. It should be noted that the number of positions is not fixed and can be flexibly designed according to actual application scenarios (such as voltage regulation requirements and equipment power levels), for example, different specifications such as 7 positions, 11 positions, and 14 positions can be set.

[0055] Figures 8 to 10 The example illustrates the action process in which each pin element in the mechanical stop device acts on the first transmission element 39 and subsequently drives the first transmission element 39 to act on the second transmission element 40.

[0056] exist Figure 8 In this configuration, the on-load tap changer 10 is not in its extreme position (e.g., any one of positions 2 to 8). Here, neither the first pin element 41 nor the second pin element 42 on the second gear 38 contacts the radially extending section 56 of the first transmission element 39, thus no driving force is applied to the first transmission element 39. At this time, the first transmission element 39 and the second transmission element 40 maintain their initial positions under the elastic force of the first and second spring elements. Neither the first stop section 51 nor the second stop section 52 of the second transmission element 40 contacts the stop ring 47 of the transmission shaft assembly 21, allowing the transmission shaft assembly 21 to rotate freely and enabling the on-load tap changer to switch positions.

[0057] exist Figure 9 In this configuration, the on-load tap changer 10 is in its first extreme position (e.g., position 1). Here, as the second gear 38 rotates to a specific angle, the first pin element 41 contacts the radially extending section 56 of the first transmission element 39 and drives the first transmission element 39 to rotate in a first rotation direction. During rotation, the first transmission element 39 compresses the second spring element 65, causing it to elastically deform. The second spring element 65 then transmits the driving force to the second transmission element 40, driving it to rotate in a second rotation direction. Finally, the first stop portion 43 of the first stop section 51 of the second transmission element 40 at least partially extends into the first groove 54 of the stop ring 47, thereby mechanically preventing the drive shaft assembly 21 from continuing to rotate in the first rotation direction, achieving reliable stopping at the lowest position.

[0058] exist Figure 10 In this configuration, the on-load tap changer 10 is in its second extreme position (e.g., position 9). Here, as the second gear 38 rotates to a specific angle, the second pin element 42 contacts the radially extending section 56 of the first transmission element 39 and drives the first transmission element 39 to rotate in the second rotation direction. During rotation, the first transmission element 39 compresses the first spring element 64, causing it to elastically deform. The first spring element 64 then transmits the driving force to the second transmission element 40, driving it to rotate in the first rotation direction. Finally, the second stop portion 45 of the second stop section 52 of the second transmission element 40 at least partially extends into the second groove 55 of the stop ring 47, thereby mechanically preventing the drive shaft assembly 21 from continuing to rotate in the second rotation direction, achieving a stop at the highest position.

[0059] It should be noted that the terminology used in the application documents is for descriptive purposes only and is not intended to limit the disclosure. The singular form "a" as used herein should include the plural form unless the context explicitly states otherwise. It is understood that the terms "comprising," "having," and other similar terms, when used in the application documents, specifically describe the presence of the stated operation, element, and / or component, without excluding the presence or addition of one or more other operations, elements, components, and / or combinations thereof. The term "and / or," as used herein, includes all arbitrary combinations of one or more of the associated listed items.

[0060] To facilitate understanding of the structure of the drive system for on-load tap changers of this application, the components of the drive system are shown in the accompanying drawings not to scale and / or enlarged and / or reduced. It is also understood that if an element is referred to as being on or connected to another element, then said element may be directly formed on or connected to said other element, or there may be one or more intermediate elements between them. Conversely, if the expressions "directly on" and "directly connected to" are used herein, it indicates that there are no intermediate elements.

[0061] It can also be considered that all the exemplary embodiments disclosed herein can be arbitrarily combined with each other. Finally, it should be noted that the above embodiments are only for understanding the present invention and do not constitute a limitation on the protection scope of the present invention. For those skilled in the art, modifications can be made based on the above embodiments, and these modifications do not depart from the protection scope of the present invention.

[0062] List of reference numerals in the attached diagram:

[0063] 10 On-load tap changers

[0064] 20 drive system

[0065] 21 Driveshaft Assembly

[0066] 22 motors

[0067] 23 Drive shaft

[0068] 24 control devices

[0069] 25 Mechanical stop device

[0070] 26 drive pins

[0071] 27 limit elements

[0072] 28 Matching limit elements

[0073] 29 radial grooves

[0074] 30 limit mechanism

[0075] 31 First Axis Assembly

[0076] 32 Second Axis Assembly

[0077] 33 First fixed shaft

[0078] 34 Maltese wheels

[0079] 35 First Gear

[0080] 36 dials

[0081] 37 Second fixed shaft

[0082] 38 Second Gear

[0083] 39 First transmission element

[0084] 40 Second transmission element

[0085] 41 First pin component

[0086] 42 Second pin element

[0087] 43 First stop section

[0088] 44 First mating stop part

[0089] 45 Second stop section

[0090] 46 Second mating stop

[0091] 47 Stop ring

[0092] 48 First Circular Section

[0093] 49 Second Circular Section

[0094] 50 Functional Connecting Section

[0095] 51 First Stop Section

[0096] 52 Second Stop Section

[0097] 53 Central Section

[0098] 54 First Groove

[0099] 55 Second Groove

[0100] 56 radial extension sections

[0101] 57 Connection Area

[0102] 58 Destinations

[0103] 59 Accommodating Recess

[0104] 60 Matching limit mechanism

[0105] 61 First stitch

[0106] 62 Second splice

[0107] 63 connecting rod

[0108] 64 First Spring Element

[0109] 65 Second Spring Element

[0110] 100 On-load tap changer assembly.

Claims

1. A drive system for an on-load tap changer, the drive system (20) comprising a motor (22) and a drive shaft assembly (21) having a drive shaft (23), the drive shaft (23) of the drive shaft assembly (21) being directly or indirectly connected to the on-load tap changer (10), the motor (22) being used to drive the drive shaft assembly (21) to achieve gear switching of the on-load tap changer (10). Its features are, The drive system (20) includes a mechanical stop device (25) configured to: prevent the drive shaft assembly (21) from continuing to rotate in the first rotation direction when the on-load tap changer (10) is switched to the first limit position in the first rotation direction; and prevent the drive shaft assembly (21) from continuing to rotate in the second rotation direction when the on-load tap changer (10) is switched to the second limit position in the second rotation direction opposite to the first rotation direction.

2. The drive system for an on-load tap changer according to claim 1, characterized in that, The first limit position is the lowest position of the on-load tap changer and the second limit position is the highest position of the on-load tap changer; or the first limit position is the highest position of the on-load tap changer and the second limit position is the lowest position of the on-load tap changer.

3. The drive system for an on-load tap changer according to claim 1 or 2, characterized in that, The mechanical stop device (25) has a limiting mechanism (30) and a cooperating limiting mechanism (60). The limiting mechanism (30) is operatively connected to the drive shaft assembly (21). The cooperating limiting mechanism (60) is non-rotatably mounted on the drive shaft assembly. When the on-load tap changer (10) is not in the limit position, the limiting element (27) of the limiting mechanism (30) and the cooperating limiting element (28) of the cooperating limiting mechanism (60) remain separated. When the on-load tap changer (10) is in the limit position along any rotation direction, the limiting element (27) of the limiting mechanism (30) and the cooperating limiting element (28) of the cooperating limiting mechanism (60) come into contact to prevent the drive shaft assembly (21) from continuing to rotate in that rotation direction.

4. The drive system for an on-load tap changer according to claim 3, characterized in that, A drive pin (26) is provided on one axial end face of the drive shaft assembly (21). The drive shaft assembly (21) is connected to the limiting mechanism (30) through the drive pin (26), so that the limiting element (27) of the limiting mechanism (30) can rotate around a rotation axis parallel to the rotation axis of the drive shaft assembly (21).

5. The drive system for an on-load tap changer according to claim 4, characterized in that, The limiting mechanism (30) includes a first shaft assembly (31) and a second shaft assembly (32), and the rotation axes of the first shaft assembly (31), the second shaft assembly (32) and the transmission shaft assembly (21) are all parallel. The first shaft assembly (31) includes a first fixed shaft (33), a Maltese wheel (34), a first gear (35), and a second transmission element (40). The Maltese wheel (34) and the second transmission element (40) are rotatably supported on the first fixed shaft (33). The first gear (35) is fixedly mounted or integrally formed on the side of the Maltese wheel (34) facing the second transmission element (40). The first gear (35) and the second transmission element (40) are spaced apart along the axial direction of the first fixed shaft (33). The second shaft assembly (32) includes a second fixed shaft (37), a second gear (38), and a first transmission element (39). The second gear (38) and the first transmission element (39) are rotatably supported on the second fixed shaft (37). A first pin element (41) and a second pin element (42) are provided on the side of the second gear (38) facing the first transmission element (39). The first transmission element (39) and the second gear (38) are spaced apart along the axial direction of the second fixed shaft (37). The drive pin (26) of the drive shaft assembly (21) is used to operatively connect with the Maltese wheel (34) of the first shaft assembly (31), the first gear (35) of the first shaft assembly (31) meshes with the second gear (38) of the second shaft assembly (32), the first pin element (41) and the second pin element (42) are both used to operatively connect with the first transmission element (39), the first transmission element (39) is used to operatively connect with the second transmission element (40), and the second transmission element (40) is configured as the limiting element (27).

6. The drive system for an on-load tap changer according to claim 5, characterized in that, The first transmission element (39) includes a radially extending section (56) comprising a connecting region (57) and an abutting region (58), the abutting region (58) being closer to the second gear (38) relative to the connecting region (57), and the distance between the abutting region (58) and the second gear (38) being less than the length of the first pin element and the second pin element extending from the second gear (38), the connecting region (57) being configured with a receiving recess (59). The second transmission element (40) includes a working connection section (50), which includes a first connecting piece (61) and a second connecting piece (62). The first connecting piece (61) and the second connecting piece (62) are spaced apart and connected by a connecting rod (63). The connecting rod (63) extends perpendicularly to the second fixed shaft (37) and passes through the receiving recess (59) of the first transmission element (39). A first spring element (64) and a second spring element (65) are sleeved on the connecting rod (63). The first spring element (64) is disposed between the first connecting piece (61) of the second transmission element (40) and the connection area (57) of the first transmission element (39). The second spring element (65) is disposed between the second connecting piece (62) of the second transmission element (40) and the connection area (57) of the first transmission element (39).

7. The drive system for an on-load tap changer according to any one of claims 4 to 6, characterized in that, The drive shaft assembly (21) includes a dial (36) that is non-rotatably supported on the drive shaft (23), the dial (36) having a cylindrical pin on its axial end face, the cylindrical pin being configured as the drive pin (26), and a limiting mechanism (30) having a Maltese wheel (34), the dial (36) and the Maltese wheel (34) cooperating as a Geneva mechanism.

8. The drive system for an on-load tap changer according to claim 5 or 6, characterized in that, When the on-load tap changer (10) is in the first limit position along the first rotation direction, the first pin element (41) of the second shaft assembly (32) acts on the first transmission element (39) and drives the first transmission element (39) to rotate along the first rotation direction. The first transmission element (39) further acts on the second transmission element (40) and drives the second transmission element (40) to rotate along the second rotation direction. Finally, the second transmission element (40) contacts the mating limit element (28) of the transmission shaft assembly (21) to prevent the transmission shaft assembly (21) from continuing to rotate along the first rotation direction. When the on-load tap changer (10) is in the second limit position along the second rotation direction, the second pin element (42) of the second shaft assembly (32) acts on the first transmission element (39) and drives the first transmission element (39) to rotate along the second rotation direction. The first transmission element (39) further acts on the second transmission element (40) and drives the second transmission element (40) to rotate along the first rotation direction. Finally, the second transmission element (40) comes into contact with the matching limit element (28) of the transmission shaft assembly (21) to prevent the transmission shaft assembly (21) from continuing to rotate along the second rotation direction.

9. The drive system for an on-load tap changer according to claim 6, characterized in that, The engagement limiting mechanism (60) of the drive shaft assembly (21) is constructed as a stop ring (47), which is non-rotatably mounted on the drive shaft (23). The outer circumferential surface of the stop ring (47) includes a first circumferential section (48) and a second circumferential section (49) with different diameters. A first groove (54) and a second groove (55) are provided at the transition between the first circumferential section (48) and the second circumferential section (49). The second transmission element (40) includes a first stop section (51) and a second stop section (52); the first stop section (51) is configured with a first stop portion (43), and the second stop section (52) is configured with a second stop portion (45); the functional connecting section (50), the first stop section (51), and the second stop section (52) extend radially from the central section (53) of the second transmission element (40) and are spaced apart in the circumferential direction. When the second transmission element (40) rotates in the second rotation direction, the first stop (43) can at least partially extend into the first groove (54) of the mating limiting element (28) to prevent the transmission shaft assembly (21) from rotating in the first rotation direction; and when the second transmission element (40) rotates in the first rotation direction, the second stop (45) can at least partially extend into the second groove (55) of the mating limiting element (28) to prevent the transmission shaft assembly (21) from rotating in the second rotation direction.

10. An on-load tap changer assembly, the on-load tap changer assembly (100) comprising an on-load tap changer (10) and a drive system (20) for the on-load tap changer, characterized in that, The drive system is configured as a drive system for an on-load tap changer according to any one of claims 1 to 9.

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