BG112463A - Power commutator with vacuum arc-suppression chamber and insulated phases for a step voltage regulator - Google Patents

Abstract

The power commutator is carried by a flange (1) on which is mounted a spring energy accumulator (2). By means of insulation straight bars (4), the flange (1) is connected to the three phases, which are radially spaced from each other so that between them there is an oil insulation distance (3). Each phase comprises a main vacuum arc-suppressing chamber (6) connected to a main contact system (36) and a supplementary vacuum arc-suppressing chamber (7) connected to an supplementary contact system (37). The carrying structure of the phase consists of a segment (11) of an insulation cylinder, a lower metal sector (10), a medium insulation sector (8) to which are fastened the two vacuum chambers (6, 7), and an upper insulation sector (19). which carries the resistors (25). Between the lower and upper sectors is mounted via bearings a central actuating shaft (17), which actuates the main contact system (36) and the toe cam (26) acting on a roller (27) of the lever system (12), which controls the main vacuum chamber (6). On the shaft (17) is mounted via bearings a coaxially hollow insulation shaft (18), which actuates the supplementary contact system (37) and the toe cam (28) acting on the roller (29).

Description

(54) POWER SWITCH FOR STEP VOLTAGE REGULATOR WITH VACUUM EXTINGUISHING CHAMBER AND INSULATED PHASES

FIELD OF THE INVENTION

The invention relates to a power switch used in a step voltage regulator. Step regulators are built into the power transformers and regulate their high voltage under load, ie. without interrupting the power supply to consumers. The power switch has two vacuum arc-quenching chambers per phase, and the three phases are isolated from each other.

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BACKGROUND OF THE INVENTION

Step voltage regulators are isolated phases are mainly of column type is three phases arranged one below the other. Most often they work as selected under load, ie. the same contact systems perform dialing and switching. There are fewer step regulators with isolated phases, which have a separate power switch and selected.

A power switch (1) is known, comprising three single-phase power switches arranged one below the other in an insulating cylinder and insulated relative to each other. Each single-phase power switch has one main vacuum arc quenching chamber and one auxiliary vacuum arc quenching chamber connected in series is a resistor. Two arcs with an insulating gap between them are mounted on the inner surface of the insulating cylinder. The two vacuum arc quenching chambers are connected in their upper part by one contact bridge. The two bridges are located radially at a certain angle to each other and contact in a stationary position with one of the arches. The movable contact elements of the two chambers are connected to a lever system, which serves to open and close the chambers during switching. The resistors are located around the outer surface of the insulating cylinder. The two vacuum arc-quenching chambers are mounted next to each other in the middle of the insulating cylinder between two shafts which rotate 180 ° in one change, the contact bridges passing successively through the insulating gap when the respective vacuum arc-quenching chamber is open.

The disadvantage of this power switch is that it takes up a lot of space and is inconvenient for mounting and dismounting in the oil pan. It is difficult to monitor its operation, revisions and possible repairs. Another disadvantage is that the nominal and the circulating are not switched separately

2/14 current, which reduces the switching capacity. Another disadvantage is that the connection of the resistors in series with the auxiliary vacuum arc quenching chamber is difficult.

In another known power switch of this type (2) a separate disconnection of the rated current from the main chamber and of the circulating current - from the auxiliary chamber is performed. This is achieved by the two vacuum arc-quenching chambers being fixed to each other next to the inner wall of the insulating cylinder, and a main drive shaft is mounted in the middle of the cylinder between two disks. A tubular auxiliary shaft is coaxially mounted on it. A main contact bridge is connected to the first shaft, and an auxiliary contact bridge to the second, the two bridges being located one below the other. On each of the contact bridges correspond to two contact arcs is an insulating gap between them, also located one below the other. The system for switching off and on the cameras is complicated.

The disadvantage of this power switch is that it is significantly arranged in construction. Disadvantages remain regarding the difficulties of assembly and disassembly, monitoring and control during switching.

Another power switch with isolated phases (3) is also known, in which the three single-phase power switches are on one level in an insulating cylinder of an oil vessel. Each phase occupies a sector of 120 ° and is pulled in a radial direction so as to achieve an insulating gap between them. The phase contains a main vacuum arc quenching chamber is a main contact system and an auxiliary vacuum arc quenching chamber with an auxiliary contact system. The contact systems contain one contact bridge each, which contacts an internal contact arc and an external contact arc divided in two by an insulating gap. The two contact systems are located one below the other above the two adjacent vacuum chambers. The contact bridges are driven by

3/14 vertical shaft bearing between two sectors. This shaft has a cam that acts on a lever system to turn the vacuum chambers on and off. The resistors are located above the contact systems. The spring-energy accumulator is common to the three phases, but is connected to the phases by insulating shafts. It is located below the phases. Between it and the bottom of the oil tank there are mechanisms for activating the spring energy accumulator. The power switch is attached to through cantilever contact elements arranged in a circle on the cylinder of the oil tank.

The disadvantage of this power switch is that even at the beginning of the switching there is a large resistance moment, because then the vacuum chamber is opened. This requires a spring-loaded energy-efficient battery. Another disadvantage is that the spring-loaded battery is at the bottom of the oil tank, where there are also charging mechanisms. These nodes are inaccessible for monitoring and control. Another disadvantage is that the rated and circulating current are not switched separately. It is also difficult to insert the power switch into the oil pan.

In another known power switch with isolated phases (4) a separate switching of the rated and circulating current is achieved. It also contains three phases radially spaced apart and housed in an insulating cylinder. The structure of each phase is analogous to that of (3). The difference is that there are two concentrically located drive shafts, of which the central shaft works with the main vacuum arc quenching chamber, and the tubular shaft - with the auxiliary vacuum arc quenching chamber. The insulating gap of the main contact system is located radially to the main chamber, and the insulating gap of the auxiliary contact system - to the auxiliary chamber. The central shaft is connected at the top with a contact bridge, and below with a cam acting on the movable contact

4/14 of the main camera. The spring-energy accumulator is located at the bottom and is coupled to the central shaft is an overload clutch. The tubular shaft also has a contact bridge at the top and a cam at the bottom acting on the movable contact of the auxiliary chamber. It is connected to the central shaft via a freewheel clutch. At the beginning of the switch, the main vacuum chamber is switched by turning the contact bridge halfway through the entire angle made by the central shaft. The overload clutch slips and the contact bridge is stopped by a buffer. The freewheel clutch then actuates the auxiliary vacuum chamber and the auxiliary contact bridge within the second half of the operating angle. In reverse switching, the sequence of action is the same.

The disadvantage of this power switch is that the overload clutch must be very well sized and adjusted, because if it is not operated correctly, the power switch will be damaged. Here again, there are disadvantages related to the special requirement for the power characteristic of the spring-energy accumulator and its location under the contact system.

SUMMARY OF THE INVENTION

The object of the invention is to provide a power switch for a step voltage regulator is vacuum arc quenching chambers and isolated phases with separate switching of the rated current and the circulating current from the main and auxiliary vacuum arc quenching chambers. It must have a compact and simple construction. To be easily mounted in the oil pan and to be able to observe its action. The resistance moment should be the largest in the middle zone of the angle of movement of the movable elements, as a result of which the operation of the spring-energy accumulator should be facilitated.

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The problem is solved with a power switch for step voltage regulator, containing three phases occupying sectors of 120 ° and radially spaced from each other with insulated distances between them. Each phase has one main vacuum arc quenching chamber connected to the main contact system and one auxiliary vacuum arc quenching chamber connected to the auxiliary contact system. Each contact system comprises an internal contact arc, a contact bridge and an external contact arc interrupted at a specific location by an insulating gap. The supporting structure consists of an insulating segment and two sectors arranged in storeys. Between the sectors are located the two vacuum chambers, which in their lower part are connected by a lever mechanism, which performs the switching off and on of the vacuum chambers. There is also a vertical drive shaft mounted to both sectors. It has a cam at its lower end acting on the lever mechanism, and at its upper end it carries a main contact bridge and an auxiliary contact bridge. The drive shaft is coupled to a spring-energy accumulator by an insulating shaft.

According to the invention, the spring-energy accumulator is located on a supporting flange, to which the three phases isolated to each other are attached by means of insulating rails. Each phase has a central drive shaft connected above by a contact bridge of the main contact system and below - by a cam contacting the rolling bearing of the main lever drive system. A hollow shaft is mounted on the drive shaft, connected at the top with a contact bridge of the auxiliary contact system and at the bottom - with a cam in contact with the rolling bearing of the auxiliary drive system. The two rolling bearings are located one below the other in the middle of the respective phase. The insulating gaps of the external arcs of the two contact systems are also located one below the other in the middle of the respective phase. They are radially oriented relative to the rolling bearings.

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The supporting structure of each phase consists of a segment of an insulating cylinder and a metal sector arranged in layers, an insulating sector to which the two vacuum arc quenching chambers are attached, and an upper insulating sector. Between the lower and upper sector is mounted the central drive shaft, and on it is coaxially mounted the hollow shaft, which is preferably made of insulating material.

The two vacuum arc quenching chambers are located next to each other next to the insulation segment, symmetrical to the center of the phase. The two rolling bearings are offset from their drive systems in the center of the phase. The bearing of the main vacuum arc quenching chamber is attached to the tail of a carrier mounted by an axis to a U-shaped bracket mounted to the lower sector. This bracket is located radially opposite the main vacuum arc quenching chamber. The other bearing is mounted above the first L-shaped tail bearing mounted in a similar manner to a U-shaped bracket located radially opposite the auxiliary vacuum arc quenching chamber.

The central shaft of each phase is connected by an insulating shaft to the spring-energy accumulator by means of a gear consisting of a central gear mounted on the drive shaft of the spring-energy accumulator and three satellite wheels connected to the insulating shafts. Thus, the 90 ° rotation of the spring-energy accumulator shaft is converted to a 120 ° rotation of the central shaft.

The auxiliary contact bridge is located 20 ° from the center of the phase, and its rotation of 40 ° is limited by buffers. The main contact bridge rotates 120 ° on one switch. Thus, the main vacuum arc extinguishing chamber is open in the range from 40 ° to 80 °, and the auxiliary vacuum arc extinguishing chamber - in the range from 80 ° to 120 °. This ensures separate switching between the rated and circulating currents. The resistors are mounted on the upper insulation

7/14 sector. The three phases are reinforced in their lower part by ribbed insulators. In order to avoid possible misalignment, the insulating shafts can have semi-cardan connectors at both ends.

The power switch is attached via its support flange to the upper flange of the oil pan.

An advantage of the power switch is the isolated phases according to the invention, that with a simple and compact design a separate disconnection of the rated current from the main vacuum arc quenching chamber and of the circulating current from the auxiliary vacuum arc quenching chamber is achieved. The switching is completely symmetrical in both directions. Another advantage is that the large resistance moments from the opening of the vacuum arc quenching chambers are grouped in the middle range of rotation. This relieves the load on the spring-energy accumulator.

Another advantage is that when a power switch is installed in the oil tank, the operation of the spring-energy accumulator and the contact system can be observed.

Another advantage is that there are no mechanisms at the bottom of the oil tank, and inserting and removing the power switch in the oil tank is very easy.

EXPLANATION OF THE ATTACHED FIGURES

An exemplary embodiment of the power switch for step voltage regulator is vacuum arc quenching chambers and isolated phases, according to the invention is shown in the attached figures, of which:

Figure 1 is a longitudinal section through two of the phases of the power switch.

Figure 2 - cross section on three levels:

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I - above the resistors; II - above the contact system of the main vacuum arc quenching chamber; III - above the contact system of the auxiliary vacuum arc quenching chamber.

Figure 3 - cross section of three other levels: IV - above the supports of the vacuum arc quenching chambers; V - above the rolling bearings driving the vacuum arc quenching chambers; VI - through the bearings of the rolling bearings.

Figure 4 - Cross section through the bearings of the rolling bearings on an enlarged scale.

EXAMPLES OF EMBODIMENT OF THE INVENTION

The power switch is mounted on a bearing flange 1. A known spring-energy accumulator 2 is mounted on it. The three phases A, B and C occupy one sector of 120 ° each. They are radially spaced from each other at an insulating distance 3. The contact system of each phase is attached to the bearing flange 1 by two radial insulating rails 4 and one peripheral insulating rack 5. Each phase has one main 6 and one auxiliary 7 vacuum arc quenching chamber mounted next to each other on the insulating sector 8 by support heads 9. Between the sector 8 and the metal sector 10 is attached a segment 11 of an insulating cylinder. The movable contact element of each of the two vacuum arc chambers 6 and 7 is opened and closed by a known guide system 12 supported by a contact spring 13. The current from the movable contact element of the vacuum arc chamber is made by a flexible copper braid 14 and a plug contact bracket 15. node 16.

The actuation of the contact systems is made by a metal shaft 17 and a hollow insulating shaft 18 mounted on it. The shaft 17 is mounted at the bottom of sector 10 and at the top of the upper insulating sector 19. at 120 °. He

9/14 is connected to the spring-energy accumulator 2 by an insulating shaft 20. Since the spring-energy accumulator 2 rotates its output shaft 21 at 90 ° of switching, a gear consisting of a central gear 22 and three satellite gears 23 connected to shafts 20. To correct possible misalignment, shaft 20 has semi-cardan connectors 24 at both ends. Resistors 25 are attached to the insulation sector 19. At its lower end, shaft 17 has a cam 26 which, when switched, interacts with a rolling bearing 27 actuating the main vacuum arc quenching chamber 6. At its lower end and the hollow shaft 18 there is a cam 28 which interacts with a rolling bearing 29 actuating the auxiliary vacuum arc quenching chamber 7. The connection between shaft 17 and shaft 18 is made by a freewheel coupling 30 of a pin 31 connected to a shaft 17 and a sleeve 32 with an arc gap 33 (Fig. 3) connected to a shaft 18. At the lower end of the shaft 17, below sector 10, there is a buffer 34 which limits turning in both directions. Insulators can be used to strengthen the three phases at their lower end 35.

Between the insulating sectors 8 and 19 are located below each other a main contact system 36 connected to the main vacuum arc quenching chamber 6 and an auxiliary contact system 37 connected to the auxiliary vacuum arc quenching chamber 7. The auxiliary contact system 37 has a support arm 38 connected to the upper end. on the shaft 18. On the arm 38 are mounted contact lamellae 39 with axles and contact springs 40. The lamellae 39 contact with an inner contact arc 41 and two outer contact half-arcs 42 and 43, between which there is an insulating gap 44. The contact lamellas 39 are set at an angle from 20 ° to the gap 44. When switching, they rotate at an angle of 40 °, which is limited by buffers 45.

The main contact system 36 has an analogous device with a support arm 46 connected to a shaft 17, on which the contact lamellae 48 are mounted by means of springs with springs 47. In one change they rotate at an angle of 120 °,

10/14 in contact with an internal contact arc 49 and external contact arcs 50 and 51. Between them, in the middle of the sector, there is an insulating gap 52 located above the gap 44 of the auxiliary contact system 37. To facilitate the passage of lamellae 48 through the gap 52, plastic arches 53 may be used. Plug contact assemblies 54 located at both ends of the main contact system 36 are provided for connecting the known oil vessel contact elements. The two switching rolling bearings 29 and 27 are arranged one below the other in the middle of the main contact system. contact systems, against gaps 44 and 52 (Fig. 3, Fig. 4). Bearing 27 is attached to a tail 55 of a carrier 56 mounted by an axis 57 to a U-shaped bracket 58 mounted to a sector 10. The attachment of a bearing 29 is the same, but the tail 59 is L-shaped.

The action when switching the power switch is as follows:

The spring-energy accumulator 2 rotates its output shaft 21 at an angle of 90 °, which is transformed by a gear 22-23 at an angle of 120 ° for shafts 20 and 17. The main contact lamellae 48 rotate clockwise (Fig. 2). The main vacuum arc quenching chamber 6 is switched off by a cam 26 and a bearing 27 after 40 °, and the switching on is done at 80 °. In this interval the currentless passage of lamellae 48 through the gap 52 takes place. During this time the load current flows through the auxiliary vacuum arc quenching chamber 7 and through the resistors 25. After 80 ° thumb 31 the free travel 33 has passed and contact lamellae 39 are rotated. similarly, the auxiliary contact system 37 is switched within the last 40 ° rotation. The reverse switching is done in the same way.

Claims (7)

PATENT CLAIMS 1. Power switch for step voltage regulator with vacuum arc quenching chambers and insulated phases, containing three radially spaced phases at one level connected to a spring non-energy accumulator, each phase having one main vacuum arc quenching chamber is a main contact system and one auxiliary vacuum chamber auxiliary contact system, each contact system consisting of an internal contact arc, a contact bridge coupled with a vertical drive shaft and an external contact arc interrupted at a specific location by an insulating gap, and the movable contact element of each vacuum arc chamber being connected to a lever system. roller or with a rolling bearing periodically in contact with a cam mounted on the lower end of the drive shaft, characterized in that the spring-energy accumulator (2) is located on a bearing flange (1), to which by insulating rails (4, 5) are the three phases (A, B, C) are fixed, each phase has a central drive shaft (17) connected above is a contact bridge (46) of the main contact system (36) and below - with a cam (26) in contact with the rolling bearing (27) of the main lever drive system (12), on the drive shaft (17) is mounted a hollow shaft ( 18) connected above by a contact bridge (38) of the auxiliary contact system (37) and below by a cam (28) in contact with the rolling bearing (29) of the auxiliary drive system, the two rolling bearings (27, 29) being located one below another in the middle of the respective phase, and the insulating gaps (44, 52) of the outer arcs (42,43, 50, 51) of the two contact systems (36, 37) are also installed one below the other. 12/14 in the middle of the respective phase, radially directed relative to the rolling bearings (27, 29). Power switch according to claim 1, characterized in that the supporting structure of each phase (A, B, C) consists of a segment (11) of an insulating cylinder and a stacked metal sector (10), an insulating sector (8). , to which the two vacuum arc quenching chambers (6, 7) and the upper insulating sector (19) are attached, the central drive shaft (17) being mounted between sectors (10 and 19), and the hollow shaft (18) being coaxially mounted on it. preferably made of insulating material. Power switch according to claims 1 and 2, characterized in that the two vacuum arc quenching chambers (6, 7) are arranged next to the insulating segment (11) symmetrically with respect to the center of the phase, and the two rolling bearings (27, 29) ) are displaced relative to their drive systems (12) in the center of the phase, as a bearing (27) is attached to the tail (55) of a carrier (56) mounted by an axis (57) to a U-shaped bracket (58) mounted on a sector 10) and located radially opposite the main vacuum arc quenching chamber (6), and a bearing (29) is mounted above a bearing (27) of a L-shaped tail (59) mounted in a similar manner to a U-shaped bracket (58) located radially relative to the auxiliary vacuum arc quenching chamber (7). Power switch according to claims 1, 2 and 3, characterized in that the central shaft (17) of each phase (A, B, C) is connected by an insulating shaft (20) to the spring-energy accumulator (2) by means of gear consisting of a central gear (22) mounted on the drive shaft (21) of the spring energy accumulator (2) and three satellite wheels (23) connected to 13/14 the insulating shafts (20), thus the 90 ° rotation when switching the shaft (21) is converted to a 120 ° rotation on the shaft (20). Power switch according to claims 1, 2, 3 and 4, characterized in that the auxiliary contact bridge (38) is located at 20 ° from the center of the phase, its rotation of 40 ° being limited by buffers (45), the main contact bridge (46) is rotated 120 ° in one switch so that the main vacuum arc suppression chamber (6) is open in the range from 40 ° to 80 ° and the auxiliary vacuum arc extinguishing chamber (7) in the range from 80 ° to 120 °, thus ensuring separate switching of the rated and circulating current. Power switch according to claims 1, 2, 3, 4 and 5, characterized in that the resistors (25) are mounted on the upper insulating sector (19) and the three phases are reinforced with ribbed insulators (35). Power switch according to claims 1, 2, 3, 4, 5 and 6, characterized in that in order to absorb the alignment errors, the insulating shafts (20) can have semi-cardan shafts (24) at their ends.