Miniaturized on-load voltage regulation switch and on-load voltage regulation distribution transformer

Abstract

The invention discloses a miniaturized on-load voltage regulation switch and an on-load voltage regulation distribution transformer, the switch comprises a driving mechanism assembly, a transmission mechanism assembly, a selection switch assembly, a change-over switch assembly, a transition element and an insulation installation mainboard, the driving mechanism assembly comprises a servo motor, a gearbox, a driving cam disc, a transmission gear and a driving deflector rod wheel, the transmission mechanism assembly comprises a groove strip, a linkage mechanism and a transmission shaft, the servo motor drives the groove strip, the linkage mechanism and the transmission shaft to act in a timing sequence by means of the gearbox, the driving cam disc, the transmission gear and the driving deflector rod wheel, then the selection switch assembly and the change-over switch assembly are driven to act, and conversion of voltage regulation gears is completed. A linear mechanism design is adopted, the structure is simple and compact, the conventional size of the distribution transformer hardly needs to be changed when the distribution transformer is installed, a bridging principle can be adopted, a non-excitation switch is directly replaced by an on-load voltage regulation switch, and the on-load voltage regulation switch is used for directly transforming the non-excitation distribution transformer into the on-load voltage regulation distribution transformer.

Description

Technical Field

[0001] The device relates to the technical field of electric power products, and in particular to a miniaturized on-load voltage regulating switch and an on-load voltage regulating distribution transformer. Background Art

[0002] The distribution transformer is the last transformer of the power supply network. It is used in various fields of national economy and people's livelihood, and is spread all over every corner of urban and rural areas. The number is huge. The existing distribution transformers are all off-excitation voltage regulation mode. When regulating the voltage, it is necessary to cut off the power supply first, and then manually adjust the off-excitation voltage regulating switch. After the adjustment is completed, the power supply can be restored. Since the voltage can only be adjusted by power outage, and it cannot be adjusted in time, the distribution transformer in the actual power supply network is equivalent to no voltage regulation measures, resulting in low power supply voltage qualification rate, poor stability, abnormal operation of electrical equipment, and increased losses of the distribution transformer itself and electrical equipment. With the continuous improvement and development of social economy and power grid, the requirements for voltage quality will become higher and higher, and therefore the reliability requirements for on-load voltage regulation distribution transformers will become higher and higher. The core component of the on-load voltage regulation distribution transformer is the on-load voltage regulating switch, which puts higher requirements on the on-load voltage regulating switch.

[0003] In recent years, there have been cases where the on-load voltage regulator of the main transformer has been applied to the distribution transformer to achieve on-load voltage regulation. However, the on-load voltage regulator of the main transformer is large in size and requires regular maintenance. It cannot meet the reliability requirements of the distribution transformer and is not suitable for a large number of distribution transformers. There are also on-load voltage regulators on the market that use spring energy storage and permanent magnet and electromagnetic drive methods for distribution transformers. Although vacuum arc extinguishing is also used, this type of drive method has a large impact force during drive transmission, which affects the service life of the on-load voltage regulator related components, so that its life cycle cannot meet the design life cycle of the distribution transformer, and is not suitable for use in a large number of distribution transformers. At the same time, since most of the current distribution transformers are non-excitation distribution transformers, if all are replaced with on-load voltage regulation distribution transformers, the cost will be very high. In view of the actual market situation, a miniaturized on-load voltage regulator is proposed that is suitable for both the transformation of old distribution transformers and new on-load voltage regulation distribution transformers.

[0004] MR of Germany has applied for the following Chinese invention patents in China: 1. Application number 201380020207.9, invention name "On-load tap changer"; 2. Application number 201380020450.0, invention name "On-load tap changer"; 3. Application number 201380020742.4, invention name "On-load tap changer"; 4. Application number 201380020745.8, invention name "On-load tap changer". The core of the above four invention patents is to operate not only the selector contact unit but also the switch device for uninterrupted on-load switching by means of a common motor drive device without an intermediate accumulator and by means of a bevel gear transmission device. However, the transmission mechanism and operating mechanism of the above four patents have complex mechanical structures and high costs. At the same time, their design concepts do not explain the life cycle and maintenance issues of the on-load tap changer. For the high reliability requirements of distribution transformers, on-load tap changers require higher reliability requirements. In addition, their design principles and structures cannot be directly used for on-load voltage regulation of domestic non-excitation distribution transformers. If their switches are to be used for transformation, the transformation cost will be greatly increased.

[0005] Jinan Aidi Electrical Equipment Co., Ltd. has applied for a Chinese invention patent with the following application number in China: Application number: 201710019736.7. It mainly solves the problems of complex structure and high cost of on-load voltage-changing switches in the original market, simplifies the structure and solves the problem of regular maintenance. Its design structure and principle cannot be directly used for on-load voltage-changing transformation of domestic non-excitation distribution transformers. If its switch is to be used for transformation, the transformation cost will be greatly increased. Summary of the invention

[0006] The purpose of the present invention is to provide a miniaturized on-load voltage regulating switch and an on-load voltage regulating distribution transformer, so as to solve the problem of the on-load voltage regulating distribution transformer in the prior art requiring regular maintenance due to on-load voltage regulating switching, and at the same time solve the problem of the on-load voltage regulating switch in the prior art being large in size and inconvenient to install, so as to realize the miniaturization of the on-load voltage regulating switch, so that it can be installed without changing the size and shape of the conventional distribution transformer, realize the long life and maintenance-free characteristics of the on-load voltage regulating switch, and make its life cycle equal to the life of the distribution transformer body. At the same time, the principle of the miniaturized on-load voltage regulating switch is also designed and upgraded according to the principle of the off-excitation voltage regulating switch used for the existing off-excitation distribution transformer.

[0007] In order to achieve the above object, the present invention adopts the following technical scheme: A miniaturized on-load voltage regulating switch, characterized in that it comprises a driving mechanism assembly, a transmission mechanism assembly, a selection switch assembly, a switching switch assembly, a transition element, and an insulating mounting mainboard, wherein the selection switch assembly, the switching switch assembly, and the transition element each have three phases; The driving mechanism assembly includes a servo motor, a gearbox, a driving cam plate, a transmission gear, and a driving lever wheel; The transmission mechanism assembly includes slot bars, a linkage mechanism, and a transmission shaft; The selection switch assembly of each phase includes a guide rod, a moving contact assembly, a stationary contact assembly, and an insulating bracket; The three-phase switching switch assembly includes a driving cross arm, a mounting bracket, and a vacuum interrupter. The vacuum interrupter has three phases, and the three-phase vacuum interrupters are driven by the same driving cross arm. The servo motor is connected to the gearbox and installed on the gearbox; The driving cam plate, the transmission gear, and the driving lever wheel are all installed at the bottom of the gearbox; The groove bar is mounted on the linkage mechanism, and the linkage mechanism is mounted on the insulating mounting main board; The three-phase selection switch assembly, the switching switch assembly, and the transition element are all mounted on the insulating mounting mainboard; The servo motor drives the gearbox to move, the gearbox drives the driving cam plate to rotate, the driving cam plate drives the transmission gear to move, and the transmission gear drives the driving lever wheel to move; the driving cam plate drives the driving cross arm to move through the transmission shaft, and the driving cross arm drives the three-phase vacuum interrupter to move, thereby completing the gear switching; the driving lever wheel drives the slot bar to move, the slot bar drives the linkage mechanism to move, and the linkage mechanism drives the moving contact assembly to move and then selects the corresponding static contact in the static contact assembly for electrical connection, thereby completing the gear selection.

[0008] According to a preferred embodiment of the present invention, a gear is arranged on the driving cam plate, the gear is meshed with the transmission gear, and the rotation of the gear drives the transmission gear to rotate; different cams and grooves are arranged in the driving cam plate, and the transmission shaft drives the vacuum arc extinguishing chamber to have a timed action as the groove moves.

[0009] According to a preferred embodiment of the present invention, a lever and a limit block are provided on the driving lever wheel. The driving lever wheel drives the groove bar to move linearly through the lever, and the rotation of the driving lever wheel is converted into a linear movement of the groove bar. When the gear selection is completed, the limit block engages with a groove tooth on the groove bar for positioning and limiting.

[0010] According to a preferred embodiment of the present invention, the driving cam plate and the driving lever wheel rotate synchronously, respectively driving the switching switch assembly and the selection switch assembly to perform sequential actions to complete the switching of the voltage regulating gear.

[0011] According to a preferred embodiment of the present invention, the linkage mechanism includes a linear guide rail, a linkage screw, and three sliders. The groove bar is fixed on the linkage screw. The linear slide rail on the linear guide rail and the linkage screw are fixedly connected to the slider. The linear guide rail is fixedly mounted on the insulating mounting main board through two linear slide blocks thereon, and the slider drives the moving contact assembly to move linearly.

[0012] According to a preferred embodiment of the present invention, the moving contact assembly includes two moving contacts and a moving contact seat, the moving contact is mounted on the moving contact seat, the moving contact seat is mounted on the guide rod, the moving contact seat moves linearly on the guide rod, and the guide rod is fixedly mounted on the insulating bracket; the static contact assembly includes a plurality of static contacts and a static contact integrated seat arranged in a straight line, a plurality of the static contacts are mounted and fixed on the static contact integrated seat, and the static contact integrated seat is fixedly connected to the insulating bracket and the insulating mounting mainboard via fixing studs.

[0013] According to a preferred embodiment of the present invention, protrusions are arranged on the upper and lower sides of the static contact integrated seat, and the protrusions are located outside the gap between the static contacts. The plane of the protrusion on the upper side of the static contact integrated seat is higher than the upper plane of the static contact, and the plane height of the protrusion on the lower side of the static contact integrated seat is lower than the lower plane of the static contact.

[0014] According to a preferred embodiment of the present invention, the three-phase vacuum arc extinguishing chambers are arranged in a straight line, a three-phase opening arm is provided on the driving cross arm, and the moving contact part of the vacuum arc extinguishing chamber is fixedly connected to the driving cross arm through the opening arm; a three-phase arc extinguishing chamber mounting seat is provided on the mounting bracket, and the static contact part of the vacuum arc extinguishing chamber is mounted and fixed on the mounting bracket through the arc extinguishing chamber mounting seat.

[0015] According to a preferred embodiment of the present invention, there are two driving cross arms and two mounting brackets, the two driving cross arms are connected and fixed by two connecting blocks, the transmission shaft is connected to one of the connecting blocks, driving the connecting block to move laterally and then driving the driving cross arm to move laterally; the two driving cross arms move between the two mounting brackets, and the mounting bracket has a guiding effect on the driving cross arms.

[0016] An on-load voltage-regulating distribution transformer, characterized in that the on-load voltage-regulating distribution transformer adopts the miniaturized on-load voltage-regulating switch of any one of the preceding claims, comprising a voltage-regulating main circuit and a transition circuit, wherein when the on-load voltage-regulating distribution transformer is in normal operation, the voltage-regulating main circuit is in a conducting state, and the transition circuit is in a disconnected state; when the voltage-regulating gear is switched, the switching switch assembly has a timed action, so that the transition circuit is first turned on, and the voltage-regulating main circuit is disconnected, and the two moving contacts in the moving contact assembly in the selection switch assembly select the corresponding static contacts in the static contact assembly to connect, thereby completing the voltage-regulating gear selection, and the switching switch assembly has a timed action, so that the voltage-regulating main circuit is turned on, and the transition circuit is disconnected, thereby completing the gear switching; When the jumper principle is adopted, the transition circuit is fixed at a certain tapping position of the transformer voltage regulating winding, and the two moving contacts in the moving contact assembly of the miniaturized on-load voltage regulating switch in the voltage regulating main circuit are electrically connected to the two corresponding static contacts in the static contact assembly, and the two static contacts are electrically connected to the two corresponding tapping taps of the transformer high-voltage coil voltage regulating winding; when the linear voltage regulation principle is adopted, the transition circuit changes step by step with the change of the voltage regulating main circuit, and the two moving contacts in the moving contact assembly of the miniaturized on-load voltage regulating switch in the voltage regulating main circuit are electrically connected to a corresponding static contact in the static contact assembly, and the static contact is electrically connected to a corresponding tapping tap of the transformer high-voltage coil voltage regulating winding.

[0017] Compared with the prior art, the beneficial effect of the present invention is that a miniaturized on-load voltage-regulating switch is invented, which is installed on the cover of the distribution transformer, the switch body is located below the cover, and the servo motor of the switch driving part is located above the cover; the miniaturized on-load voltage-regulating switch is installed in the distribution transformer without changing the shape and volume of the conventional distribution transformer as much as possible, which greatly reduces the production cost increased by the large volume of the switch; it achieves more than 300,000 trouble-free and maintenance-free continuous voltage regulation actions, and can be maintenance-free within the life cycle of the distribution transformer, thereby improving the reliability of the on-load voltage regulation of the distribution transformer; at the same time, it is realized that the off-excitation voltage-regulating switch in the off-excitation distribution transformer can be directly replaced with a miniaturized on-load voltage-regulating switch to be used as an on-load voltage-regulating distribution transformer without changing the original transformer volume and coil wiring method. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of a miniaturized on-load voltage regulating switch of the present invention; Figure 2 A is a schematic diagram of the overall structure of a miniaturized on-load voltage regulating switch without a housing; Figure 3 This is a schematic diagram B of the overall structure of a miniaturized on-load voltage regulating switch without a housing; Figure 4 This is a schematic diagram C of the overall structure of a miniaturized on-load voltage regulating switch without a housing; Figure 5 It is a structural schematic diagram of a miniaturized on-load voltage regulating switch of the present invention without the driving mechanism component; Figure 6 It is a structural schematic diagram of a switching switch assembly of a miniaturized on-load voltage regulating switch of the present invention; Figure 7 It is a structural schematic diagram of a driving mechanism component of a miniaturized on-load voltage regulating switch of the present invention; Figure 8 It is a schematic diagram of the linear voltage regulation principle and voltage regulation action timing of a miniaturized on-load voltage regulating switch of the present invention; Fig. 9 The present invention is a schematic diagram of the voltage regulation action timing of the jumper principle of a miniaturized on-load voltage regulating switch which can be directly used for the transformation of an off-excitation distribution transformer. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with the accompanying drawings. The embodiments described below are only used to more clearly illustrate the technical solution of the present invention. They are selected embodiments of the present invention, not all embodiments, and cannot be used to limit the scope of protection of the present invention. All other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1-Figure 7The present invention discloses a miniaturized on-load voltage regulating switch, comprising a driving mechanism assembly 1, a transmission mechanism assembly 2, a selection switch assembly 3, a switching switch assembly 4, a transition element 5, and an insulating mounting mainboard 6. The selection switch assembly 3, the switching switch assembly 4, and the transition element 5 each have three phases. Insulating shells 7.1 and 7.2 are arranged outside the selection switch assembly 3 and the switching switch assembly 4. The transition element 5 is located outside the insulating shell 7.2 and is fixed on the insulating mounting mainboard 6 through fixing studs; the driving mechanism assembly 1 comprises a servo motor 1.1, a gearbox 1.2, a driving cam plate 1.3, a transmission gear 1.4, and a driving lever wheel 1.5; the transmission mechanism assembly 2 comprises a groove bar 2.1, a linkage mechanism 2.2, and a transmission shaft 2.3; each phase selection switch assembly 3 comprises a guide rod 3.1, a moving contact assembly 3.2, a static contact assembly 3.3, and an insulating bracket 3.4; each phase switching switch assembly 4 comprises a driving cross arm 4.1, a mounting bracket 4.2, and a vacuum interrupter 4.3; each Each phase has two vacuum interrupter chambers 4.3; the servo motor 1.1 is connected to the gearbox 1.2 and installed on the gearbox 1.2; the driving cam plate 1.3, the transmission gear 1.4, and the driving lever wheel 1.5 are all installed at the bottom of the gearbox 1.2; the groove 2.1 is installed on the linkage mechanism 2.2; the linkage mechanism 2.2 is installed on the insulating mounting main board 6; the selection switch assembly 3, the switching switch assembly 4, and the transition element 5 are all installed on the insulating mounting main board 6; the linkage mechanism 2.2 includes It includes a linear guide 2.2.1, a linkage screw 2.2.2, and three sliders 2.2.3. The groove 2.1 is fixed on the linkage screw 2.2.2. The linear slide 2.2.1.1 and the linkage screw 2.2.2 on the linear guide 2.2.1 are fixedly connected to the slider 2.2.3. The linear guide 2.2.1 is fixedly mounted on the insulating mounting main board 6 through two linear slide blocks 2.2.1.2 thereon. The slider 2.2.3 drives the moving contact assembly 3.2 to move linearly.

[0021] The moving contact assembly 3.2 of each phase includes two moving contacts 3.2.1 and a moving contact seat 3.2.2. The moving contact 3.2.1 is installed on the moving contact seat 3.2.2. The moving contact seat 3.2.2 is installed on the guide rod 3.1. The moving contact seat 3.2.2 moves linearly on the guide rod 3.1. The guide rod 3.1 is fixedly installed on the insulating bracket 3.4; the static contact assembly 3.3 includes a plurality of static contacts 3.3.1 and a static contact integrated seat 3.3.2 arranged in a straight line. The plurality of static contacts 3.3.1 are installed and fixed on the static contact integrated seat 3.3.2. The static contact integrated seat 3.3.2 is fixedly connected to the insulating bracket 3.4 and the insulating mounting mainboard 6 through fixing studs. Protrusions 3.3.2.1 are arranged on the upper and lower sides of the static contact integrated seat 3.3.2, and the protrusions 3.3.2.1 are located outside the gap between the static contacts 3.3.1. The plane of the protrusions 3.3.2.1 on the upper side of the static contact integrated seat 3.3.2 is higher than the upper plane of the static contact 3.3.1, and the plane height of the protrusions 3.3.2.1 on the lower side of the static contact integrated seat 3.3.2 is lower than the lower plane of the static contact 3.3.1.

[0022] A three-phase split arm 4.1.1 is arranged on the driving cross arm 4.1, and the moving contact parts of the two vacuum interrupters 4.3 of each phase are fixedly connected to the driving cross arm 4.1 through the two split arms 4.1.1; a three-phase interrupter mounting seat 4.2.1 is arranged on the mounting bracket 4.2, and the static contact parts of the two vacuum interrupters 4.3 of each phase are mounted and fixed on the mounting bracket 4.2 through the two interrupter mounting seats 4.2.1. There are two driving cross arms 4.1 and mounting bracket 4.2, and the upper and lower driving cross arms 4.1 are connected and fixed through two connecting blocks 4.1.2. The transmission shaft 2.3 is connected to one of the connecting blocks 4.1.2, driving the connecting block 4.1.2 to move horizontally and then driving the driving cross arm 4.1 to move horizontally; the upper and lower driving cross arms 4.1 move between the two mounting brackets 4.2, and the mounting bracket 4.2 has a guiding effect on the driving cross arm 4.1.

[0023] The servo motor 1.1 drives the gearbox 1.2 to move, and the gearbox 1.2 drives the driving cam plate 1.3 to rotate. The driving cam plate 1.3 is provided with a gear, and the gear is meshed with the transmission gear 1.4. The driving cam plate 1.3 rotates to drive the transmission gear 1.4 to rotate, and the transmission gear 1.4 drives the driving lever wheel 1.5 to move. The driving cam plate 1.3 drives the driving cross arm 4.1 to move through the transmission shaft 2.3, and the driving cross arm 4.1 drives the opening arm 4.1.1 to move and then drives the vacuum interrupter 4.3 to move, so as to complete the gear switching; the driving lever wheel 1.5 is provided with a lever 1.5.1 and a limit block 1.5 .2, the driving lever wheel 1.5 enters the groove between the groove teeth 2.1.1 on the slot 2.1 through the lever 1.5.1 to drive the slot 2.1 to move linearly, and the circular rotation of the driving lever wheel 1.5 is converted into a linear movement of the slot 2.1, the slot 2.1 drives the linkage mechanism 2.2 to move, the linkage mechanism 2.2 drives the moving contact assembly 3.2 to move and then selects the corresponding static contact 3.3.1 in the static contact assembly 3.3 for electrical connection to complete the gear selection. After the gear selection is completed, the limit block 1.5.2 on the driving lever wheel 1.5 meshes with a groove tooth on the slot 2.1 to perform positioning and limiting.

[0024] See also Figure 8 , Fig. 9 The present invention is a miniaturized on-load voltage regulating switch, which is described for two different voltage regulating and wiring principles. By adjusting the electrical connection mode and action sequence of each component in the switch structure, two switches with different principles can be realized and can be applied in different occasions. Figure 8 This is a schematic diagram of the principle of a conventional linear on-load voltage regulator; see Fig. 9 , adopting the jumper principle, can be directly used to transform the off-excitation distribution transformer into the on-load voltage-regulating distribution transformer, that is, the miniaturized on-load voltage-regulating switch of the present invention is used to directly replace the off-excitation on-load voltage-regulating switch.

[0025] See also Figure 8 , is the timing principle of the linear voltage regulation principle and the on-load voltage regulation gear conversion principle: A and D2 are the main circuit, B, R, D1 are the transition circuit, and the timing of switching from the N+1 tap of the voltage regulating winding to the N tap is: Step 1: The moving contacts A and B are connected to the N+1 tap, and the vacuum interrupters D1 and D2 are connected. The current flows from the N+1 tap through the moving contact A and the vacuum interrupter D2.

[0026] Step 2: The vacuum interrupter D2 is disconnected, the moving contact A is disconnected from the N+1 tap, and the moving contact B is still connected to the N+1 tap. The current flows from the N+1 tap through the moving contact B, the transition element 6, and the vacuum interrupter D1.

[0027] Step 3: The moving contact B is still connected to the N+1 tap, and the moving contact A is switched from the N+1 tap with no current to the N tap. The current flows from the N+1 tap through the moving contact B, the transition element 6, and the arc extinguishing chamber D1.

[0028] Step 4: The moving contact B is still connected to the N+1 tap, the vacuum interrupter D2 is closed, the moving contact A is connected to the N tap, the current flows from the N+1 tap through the moving contact B, the transition element 6, and the vacuum interrupter D1, and the current flows from the N tap through the moving contact A and the vacuum interrupter D2. At this time, a short circulating current is generated between the N+1 tap and the N tap.

[0029] Step 5: The vacuum interrupter D1 is disconnected, the moving contact B is disconnected from the N+1 tap, the moving contact A is still connected to the N tap, and the current flows from the N tap through the moving contact A and the vacuum interrupter D2.

[0030] Step 6: The moving contact A is still connected to the N tap, and the moving contact B is switched from the N+1 tap with no current to the N tap. The current flows from the N tap through the moving contact A and the vacuum interrupter D2.

[0031] Step 7: The moving contact A is still connected to the N tap, the vacuum interrupter D1 is connected, the moving contact B is connected to the N tap, and the current flows from the N tap through the moving contact A and the vacuum interrupter D2.

[0032] See also Fig. 9 , is a schematic diagram of the action sequence of the on-load voltage regulator using the jumper principle. A1, D1, A2 are the main circuits, R, D2 are the transition circuits, and the voltage regulation principle sequence from one gear to another: Step 1: The vacuum interrupter D1 is connected, the moving contact A1 is connected to the tap 2, the moving contact A2 is connected to the tap 1, the vacuum interrupter D2 is disconnected, and the current flows through the voltage regulating windings L4 and L3, through the tap 2, the moving contact A1, the vacuum interrupter D1, the moving contact A2, the tap 1, and then through the voltage regulating windings L2, L1 and the high-voltage winding.

[0033] Step 2: The vacuum interrupter D1 is connected, the moving contact A1 is connected to the tap 2, the moving contact A2 is connected to the tap 1, the vacuum interrupter D2 is connected, the current flows through the voltage regulating windings L4 and L3 through the tap 2, the moving contact A1, the vacuum interrupter D1, the moving contact A2, the tap 1, and then through the voltage regulating windings L2, L1 and the high-voltage winding. The current flows through the voltage regulating windings L4 and L3 through the tap 2, the resistor R, the vacuum interrupter D2, and then through the high-voltage winding. At this time, a short circulating current will be generated between the taps.

[0034] Step 3: The vacuum interrupter D1 is disconnected, the moving contact A1 is disconnected from the tap 2, the moving contact A2 is disconnected from the tap 1, the vacuum interrupter D2 is still connected, and the current flows through the voltage regulating windings L4 and L3, through the resistor R, the vacuum interrupter D2, and then through the high-voltage winding.

[0035] Step 4: The vacuum interrupter D1 is still disconnected, and the moving contacts A1 and A2 perform gear selection action. The moving contact A1 moves to connect with the tap 3, and the moving contact A2 moves to connect with the tap 2. The vacuum interrupter D2 is still connected, and the current flows through the voltage regulating windings L4 and L3, through the resistor R, the vacuum interrupter D2, and then through the high-voltage winding.

[0036] Step 5: The vacuum interrupter D1 is connected, the moving contact A1 is connected to the tap 3, the moving contact A2 is connected to the tap 2, the vacuum interrupter D2 is still connected, the current flows through the voltage regulating winding L4 and L3 through the moving contact A2, the vacuum interrupter D1, the moving contact A1, and then flows through the voltage regulating winding L1 and the high-voltage winding. The current flows through the voltage regulating winding L4 and L3 through the tap 2, the resistor R, the vacuum interrupter D2, and then flows through the high-voltage winding. At this time, a short circulating current will be generated between the taps.

[0037] Step 6: The vacuum interrupter D1 is connected, the moving contact A1 is connected to the tap 3, the moving contact A2 is connected to the tap 2, the vacuum interrupter D2 is disconnected, and the current flows through the voltage regulating windings L4 and L3, through the moving contact A2, the vacuum interrupter D1, the moving contact A1, and then through the voltage regulating winding L1 and the high-voltage winding.

[0038] The above is only an explanation of two different structures and voltage regulation principles using a 5-speed on-load voltage regulating switch as an example. Other gears or other conventional on-load voltage regulating principles, such as 7-speed, 9-speed or coarse and fine adjustment, positive and negative adjustment principles, can be modified on the basis of the present invention by technicians in this technical field, and all belong to the protection scope of the present invention. The present invention describes the gear switching process of the on-load voltage regulating switch, and its selection switch component moves or selects the corresponding contacts in a no-current state, which is well known to technicians in this technical field and will not be described again. In the above entire selection and switching process, the arc is only generated in the vacuum arc extinguishing chamber, which will not pollute the transformer oil, and does not require regular oil filter maintenance or filter element replacement, which greatly saves operation and maintenance costs.

[0039] When designing the on-load voltage regulating switch dedicated to the distribution transformer, the invention is developed from the perspectives of miniaturization, maintenance-free, and a service life equal to the design service life of the transformer. The present invention adopts the flexible drive of the servo motor to drive its mechanical parts, which greatly reduces the impact force on its related parts (switching switch assembly, selection switch assembly) during the driving and transmission process of the on-load voltage regulating switch, and improves the actual service life and reliability of each switch component; two vacuum arc extinguishing chambers are arranged in the switching switch assembly. When the voltage regulating gear is switched, the two vacuum arc extinguishing chambers only act once, compared with other vacuum arc extinguishing chambers that only have one vacuum arc extinguishing chamber and need to act twice for each gear switch, and need more complex mechanical mechanism to cooperate. If the same type of vacuum arc extinguishing chambers are selected, the service life of the present invention is doubled compared with other vacuum arc extinguishing chambers that only have one vacuum arc extinguishing chamber, thereby improving the reliability of the switch; the vacuum arc extinguishing chamber in the switching switch assembly of the present invention adopts a horizontal structure, and the three-phase vacuum arc extinguishing chambers are arranged on the same straight line, which greatly reduces the overall height of the on-load voltage regulating switch; the driving cam plate of the present invention can be designed with different cams and grooves to meet the requirements of different principles or timings; at the same time, the selection switch assembly and the switching switch assembly of the on-load voltage regulating switch of the present invention are both arranged on the same insulating mounting mainboard. Compared with switches arranged on different mounting mainboards, the structural design of the present invention is simple and compact, reducing the length and width of the switch, and the overall design of the switch is miniaturized. By selecting the above scheme, the present invention realizes the characteristics of miniaturization, maintenance-free and high reliability of the on-load voltage regulating switch, which is suitable for a large number of distribution transformers. At the same time, a miniaturized on-load voltage regulating switch that can be directly used for the transformation of the off-excitation distribution transformer is invented, which directly replaces the off-excitation switch. Compared with purchasing a new on-load voltage regulating distribution transformer, the direct transformation greatly saves costs. Improvements can be made in the technical field according to the preferred embodiments of the present invention, which belong to the protection scope of the present invention.

[0040] The above is only a preferred embodiment of the present invention. It should be pointed out that for technicians in this technical field, several changes and improvements can be made without departing from the technical principles of the present invention. These changes and improvements should also be regarded as the scope of protection of the present invention.

Claims

1. A miniaturized on-load voltage regulating switch, characterized in that: It includes a driving mechanism assembly, a transmission mechanism assembly, a selection switch assembly, a switching switch assembly, a transition element, and an insulating mounting mainboard, wherein the selection switch assembly, the switching switch assembly, and the transition element each have three phases; The driving mechanism assembly includes a servo motor, a gearbox, a driving cam plate, a transmission gear, and a driving lever wheel; The transmission mechanism assembly includes slot bars, a linkage mechanism, and a transmission shaft; The selection switch assembly of each phase includes a guide rod, a moving contact assembly, a stationary contact assembly, and an insulating bracket; The three-phase switching switch assembly includes a driving cross arm, a mounting bracket, and a vacuum interrupter. The vacuum interrupter has three phases, and the three-phase vacuum interrupters are driven by the same driving cross arm. The servo motor is connected to the gearbox and installed on the gearbox; The driving cam plate, the transmission gear, and the driving lever wheel are all installed at the bottom of the gearbox; The groove bar is mounted on the linkage mechanism, and the linkage mechanism is mounted on the insulating mounting main board; The three-phase selection switch assembly, the switching switch assembly, and the transition element are all mounted on the insulating mounting mainboard; The servo motor drives the gearbox to move, the gearbox drives the driving cam plate to rotate, the driving cam plate drives the transmission gear to move, and the transmission gear drives the driving lever wheel to move; the driving cam plate drives the driving cross arm to move through the transmission shaft, and the driving cross arm drives the three-phase vacuum interrupter to move, thereby completing the gear switching; the driving lever wheel drives the slot bar to move, the slot bar drives the linkage mechanism to move, and the linkage mechanism drives the moving contact assembly to move and then selects the corresponding static contact in the static contact assembly for electrical connection, thereby completing the gear selection.

2. A miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The driving cam plate is provided with a gear, which is meshed with the transmission gear, and the rotation of the gear drives the transmission gear to rotate; different cams and grooves are provided in the driving cam plate, and the transmission shaft drives the vacuum interrupter to have a timed action as the groove moves.

3. A miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The driving lever wheel is provided with a lever and a limit block. The driving lever wheel drives the groove bar to move linearly through the lever, converting the rotation of the driving lever wheel into a linear movement of the groove bar. When the gear selection is completed, the limit block engages with a groove tooth on the groove bar for positioning and limiting.

4. The miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The driving cam plate and the driving lever wheel rotate synchronously, respectively driving the switching switch assembly and the selection switch assembly to perform sequential actions to complete the switching of the voltage regulating gears.

5. The miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The linkage mechanism includes a linear guide rail, a linkage screw, and three sliders. The groove bar is fixed on the linkage screw. The linear slide rail on the linear guide rail and the linkage screw are fixedly connected to the slider. The linear guide rail is fixedly mounted on the insulating mounting main board through two linear slide blocks thereon. The slider drives the moving contact assembly to move linearly.

6. The miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The moving contact assembly includes two moving contacts and a moving contact seat, the moving contact is mounted on the moving contact seat, the moving contact seat is mounted on the guide rod, the moving contact seat moves linearly on the guide rod, and the guide rod is fixedly mounted on the insulating bracket; the static contact assembly includes a plurality of static contacts and a static contact integrated seat arranged in a straight line, a plurality of static contacts are mounted and fixed on the static contact integrated seat, and the static contact integrated seat is fixedly connected to the insulating bracket and the insulating mounting mainboard through fixing studs.

7. A miniaturized on-load voltage regulating switch according to claim 6, characterized in that: Protrusions are arranged on the upper and lower sides of the stationary contact integrated seat, and the protrusions are located outside the gaps between the stationary contacts. The plane of the protrusions on the upper side of the stationary contact integrated seat is higher than the upper plane of the stationary contacts, and the plane height of the protrusions on the lower side of the stationary contact integrated seat is lower than the lower plane of the stationary contacts.

8. The miniaturized on-load voltage regulating switch according to claim 1, characterized in that: The three-phase vacuum interrupter chambers are arranged in a straight line, a three-phase opening arm is arranged on the driving cross arm, and the moving contact part of the vacuum interrupter chamber is fixedly connected to the driving cross arm through the opening arm; a three-phase interrupter chamber mounting seat is arranged on the mounting bracket, and the static contact part of the vacuum interrupter chamber is mounted and fixed on the mounting bracket through the interrupter chamber mounting seat.

9. The miniaturized on-load voltage regulating switch according to claim 1, characterized in that: There are two driving cross arms and two mounting brackets, and the two driving cross arms are connected and fixed by two connecting blocks. The transmission shaft is connected to one of the connecting blocks, driving the connecting block to move laterally and then driving the driving cross arm to move laterally; the two driving cross arms move between the two mounting brackets, and the mounting bracket has a guiding effect on the driving cross arms.

10. An on-load voltage-changing distribution transformer, characterized in that: An on-load voltage-regulating distribution transformer using a miniaturized on-load voltage-regulating switch according to any one of the preceding claims, comprising a voltage-regulating main circuit and a transition circuit. When the on-load voltage-regulating distribution transformer is operating normally, the voltage-regulating main circuit is in a conducting state and the transition circuit is in a disconnected state; when the voltage-regulating gear is switched, the switching switch assembly has a timed action to first conduct the transition circuit and disconnect the voltage-regulating main circuit, and the two moving contacts in the moving contact assembly in the selection switch assembly select the corresponding static contacts in the static contact assembly to connect, thereby completing the voltage-regulating gear selection, and the switching switch assembly has a timed action to conduct the voltage-regulating main circuit and disconnect the transition circuit, thereby completing the gear switching; when the bridging principle is adopted, The transition circuit is fixed at a certain tapping position of the transformer voltage regulating winding, and the two moving contacts in the moving contact assembly of the miniaturized on-load voltage regulating switch in the voltage regulating main circuit are electrically connected to the two corresponding static contacts in the static contact assembly, and the two static contacts are electrically connected to the two corresponding tapping taps of the transformer high-voltage coil voltage regulating winding; when the linear voltage regulation principle is adopted, the transition circuit changes step by step with the change of the voltage regulating main circuit, and the two moving contacts in the moving contact assembly of the miniaturized on-load voltage regulating switch in the voltage regulating main circuit are electrically connected to a corresponding static contact in the static contact assembly, and the static contact is electrically connected to a corresponding tapping tap of the transformer high-voltage coil voltage regulating winding.

Images