BG113377A - VOLTAGE STEP REGULATOR WITH HORIZONTAL POSITION - Google Patents

Abstract

The step voltage regulator contains a supporting head (4) and three single-phase power switches (X, Y, Z), arranged linearly, horizontally next to each other with provided isolation distances between them. In the bearing head (4) there are known mechanisms such as a worm gear drive shaft, a spring energy accumulator and two Maltese wheels. A flange (5) of the bearing head (4) is connected to a cover (6) of a distribution transformer. The three single-phase power switches are fixed between an upper insulating plate (1) and a lower insulating plate (2), connected by studs (3). The first power switch (X) is connected to the supporting head (4). Each power switch has one main vacuum arc extinguishing chamber (V1), one auxiliary vacuum arc extinguishing chamber (V2) and a resistor (R) housed in an insulating cylinder with top and bottom flanges. There are also contact systems with actuators. The synchronized drive of the three switches can be done in two ways: - by means of two large gears (7, 8) per phase and intermediate parasitic gears (9, 10); - by two small gears per phase (11, 12) and two insulating gear racks (13, 14).

Description

VOLTAGE STEP REGULATOR WITH HORIZONTAL POSITION

FIELD OF ENGINEERING

The invention relates to a three-phase step-down voltage regulator operating as load-selective. It is used to regulate the on-load voltage of a relatively small power transformer such as distribution transformers. In some of them, the step regulator has a horizontal arrangement and is installed under the cover of the transformer, above the active part. Vacuum arc extinguishing chambers can be used in such transformers.

PRIOR ART

A step voltage regulator (1) is known, comprising a bearing head, an insulating cylinder and a bottom. In the bearing head are located a drive shaft with a worm gear, a Maltese gear and a spring energy accumulator. Three phases are stacked in the insulating cylinder. Each phase has one main vacuum arc chamber and one auxiliary vacuum arc chamber mounted in the center of the insulating cylinder, mirrored to each other and attached to two insulating tube segments connected to the Maltese gear. Resistors are also attached to them. A certain number of U-shaped contact elements are mounted on the periphery of the insulating cylinder with terminals connected to the deviations of the regulation winding of the transformer. The fixed terminals of the two vacuum arc extinguishing chambers are connected to the U-shaped contact elements by arm-bearing contact lamellae with contact springs. The movable contact terminals of the two vacuum arc extinguishing chambers are connected by analogous arms with contact rings mounted on the inner surface of the insulating cylinder. Mechanisms for opening and closing the vacuum arc extinguishing chambers are caught on the movable contact terminals during

1/8 the switching. The switching is two-step, with the two vacuum arc extinguishing chambers opening and closing one after the other.

- The step regulator can be used in linear regulation coils or in mid-interrupted ones. It can be installed either vertically next to the active part of the transformer or horizontally above the active part under the transformer cover.

A disadvantage of this step regulator is that, due to the staggered arrangement of all six vacuum arc chambers, there is a large length. A disadvantage is that there is duplication of some elements. Another disadvantage is that, with horizontal installation, fixing the bearing head of the step regulator is difficult and requires changes in the design of the transformer tank, which makes it more expensive.

Another step voltage regulator (2) is also known, which is installed under the cover of the transformer. It has a bearing head with actuators located in it. Two horizontal insulating rails are attached to it, to which the three phases arranged next to each other are mounted. Each phase has a power switch module and a selector module. The power switch contains a vacuum arc extinguishing chamber, switching contacts and a resistor. In the selector module there are two parallel contact systems switching one after the other. The modules have a supporting structure made of cast epoxy resin lamellas. The step regulator does not have a spring energy accumulator, and the movement of the mechanisms is carried out by an electric motor and its gears. Therefore, an additional means is provided to ensure the completion of switching if the power supply is interrupted.

A disadvantage of this step regulator is that the sequence of action of the elements is complicated, which leads to the complexity of the construction and reduces the reliability of switching. Another disadvantage is that, due to the lack of a spring energy accumulator, switching depends on the speed of the relatively slower movement of the mechanisms. This affects the opening and closing speeds of the vacuum arc chamber and the resistor load. Also, regardless of the additional means, there is a real danger of the switch not being completed. This could lead to an accident. A disadvantage is that it cannot be used for regulation in a regulation coil interrupted in the middle.

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TECHNICAL ESSENCE OF THE INVENTION

The task of the invention is to create a step voltage regulator with a horizontal arrangement with three isolated phases located linearly next to each other. It should have a simplified design with small dimensions and weight. To have a simple and reliable switching scheme.

The task is solved with a three-phase step voltage regulator containing a bearing head with a spring energy accumulator and a two-step Maltese gear. There are three single-phase power switches mounted horizontally, linearly next to each other. Each power switch has one main vacuum arc extinguishing chamber, one auxiliary vacuum arc extinguishing chamber and a resistor. The vacuum arc extinguishing chambers are mounted on insulating elements connected to the driving Maltese gear. There are also movable and fixed contact elements.

According to the invention, three single-phase power switches are arranged linearly, horizontally next to each other with provided insulation distances between them and are fixed to an upper insulating plate and a lower insulating plate. The supporting structure of each power switch is composed of a vertical insulating cylinder cut into two halves, an upper disk and a lower disk. Two insulating rails carrying an auxiliary vacuum arc extinguishing chamber are mounted to the two disks via an upper arm and a lower arm. Next to it is located a main vacuum arc extinguishing chamber, attached to two insulating rails, supported by an upper arm and a lower arm to the two arms of the insulating rails of the auxiliary vacuum arc extinguishing chamber. Each of the two vacuum arc extinguishing chambers has an upper support and a lower support that are mounted to the respective insulating rails. The upper support of the main vacuum arc extinguishing chamber has a radial arm with contact lamellae. Also, the bottom bracket has a radial arm with contact slats. On the inner surface of the insulating cylinder in a horizontal plane, a certain number of U-shaped contact elements with a lead are mounted at the same angle, to which the contact lamellae of the radial arm of the upper support of the main vacuum arc extinguishing chamber contact. They are also contacted by contact lamellas located on a radial arm of a carrier attached to the insulating slats of the auxiliary vacuum arc extinguishing chamber, and this carrier is isolated from the upper carrier of this chamber. Also, the lower support of the main vacuum arc extinguishing chamber has a radial arm with contact slats which are connected to

3/8 contact ring mounted to the inner surface of the insulating cylinder.

- One of the three single-phase power switches (X in the case) is connected to a carrier head containing a worm gear drive shaft, a spring energy accumulator and two Maltese wheels. The upper Maltese wheel is coupled to the insulating rails of the main vacuum arc extinguishing chamber. The lower Maltese wheel is coupled to the insulating rails of the auxiliary vacuum arc extinguishing chamber.

On a vertical support clamped to the lower support of each of the two vacuum arc extinguishing chambers is a rocker arm, one end of which is connected to a plug clamped to the movable contact terminal of a vacuum arc extinguishing chamber. At the other end of the rocker arm is a roller which contacts during shifting with a face cam on the surface of a ring attached to the inner surface of the insulating cylinder. The electrical connection between the lower support of the main vacuum arc extinguishing chamber and its terminal is made by a flexible connection. The connection between the terminals of the two vacuum arc extinguishing chambers is made by another flexible connection.

Resistors wound by resistance wire are mounted on the sides of the four insulating rails. The four resistors are connected in series, and their two leads are connected to the support of the auxiliary vacuum arc extinguishing chamber and the above insulated radial arm support with lables.

As a first option, the transmission and synchronization of the movement from the first single-phase power switch to the other two is done by a large gear wheel connected to the neck of the lower support of the insulation rails of the auxiliary vacuum arc extinguishing chamber and a second large gear connected to the neck of the lower support of the insulation rails rails of the main vacuum arc extinguishing chamber. These two gears are bonded with two satellite gears bearing on an axle fixed to the lower isolation plate. The six main gears are the same size, and in order to reduce costs, their tooth rings are injection molded from plastic.

As a second option, the transfer and synchronization of the movement takes place in the following way. The large gears have been replaced with small gears also connected to the isolation rails of the two vacuum arc chambers. There are no parasitic gears. The upper three gears are driven by an isolation rack. Po

4/8 the same way, the lower three gears are driven by a second insulating rack identical to the first one and located below it.

* An advantage of the step voltage regulator with a horizontal arrangement, according to the invention, is that it has a simplified design with small overall dimensions and weight. Another advantage is that it has a spring energy accumulator and two vacuum arc extinguishing chambers per phase, which ensures reliable switching independent of power failure. It is also an advantage that a well-known motor drive conforming to the international standard is used. The design allows for use in both linear regulation coils and those interrupted in the middle.

EXPLANATION OF THE ATTACHED FIGURES

An exemplary embodiment of the step voltage regulator according to the invention is shown in the attached figures, of which:

Figure 1 is a longitudinal section through the step regulator showing the three phases X, Y, Z arranged side by side.

Figure 2 - Transverse section (A-A) through phase X at increased scale.

Figure 3 - longitudinal section (B-B) through phase X and the bearing head with mechanisms.

Figure 4 - longitudinal section (D-D) through phase Y rotated 90° to that of fig. 3.

Figure 5 - longitudinal section (C-C) through phase Z rotated 180° relative to that in fig. 3.

EXAMPLES OF IMPLEMENTATION OF THE INVENTION

In fig. 1 the three phases X, Y, Z are arranged next to each other and installed between the upper insulating plate 1 and the lower insulating plate 2. The two plates are connected by a certain number of pins 3. Phase X is fixed to the bearing head 4 with mechanisms. The bearing head 4 has a flange 5 which is fitted to the cover 6 of the transformer conventionally shown with a dotted line. Each phase has one main vacuum arc extinguishing chamber Vi, one auxiliary vacuum arc extinguishing chamber Ug and resistors R. The synchronization of the movement of the contact systems of the three phases can be realized in two ways:

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By large gears 7 and 8 clamped to the drive elements of the two vacuum arc extinguishing chambers Vi and V2 and parasitic gears 9 and 10 mounted to the lower insulating plate 2. Due to the large number of such gears, they are made by injection molding of plastic. So they are produced easily and quickly and are cheap.

Through two small gears 11 and 12 per phase connected to each other by means of two insulating gear racks 13 and 14.

Details of the construction are shown in Figures 2, 3, 4 and 5. The bearing head 4 is of known construction. It contains a drive shaft 15 connected to a worm gear 16 which rotates a known mechanism 17 biasing a switching spring 18 and providing a stepwise sequential rotation of two Maltese wheels 19 and 20.

The two parasitic gears 9 and 10 are mounted on an axis 21 fixed to the lower insulating plate 2.

Two identical insulating slats 23 are attached to the shaft 22 of a Maltese wheel 19, between which a carrier 24 of the main vacuum arc extinguishing chamber Vi is mounted. The metal carrier 24 has a radial arm 25, on which contact lamellae 26 with contact springs 27 are established. Contact systems of a given phase are located in an insulating cylinder, which, in order to facilitate installation, is divided into two halves 28 and 29. Along the periphery of the cylinder ten U-shaped contact elements with terminal 30 are installed. The contact lamellae 26 contact the lower contact pin of 30.

In an analogous manner, the auxiliary vacuum arc extinguishing chamber V2 is held on an identical support 24 mounted to two other insulating rails 31. Above the support 24 and isolated from it is fixed another support 32 with a radial arm 33 which carries contact lamellae 26 connected to the upper contact tongue of The U-shaped contact element 30. The resistors R are connected between the carriers 24 and 32.

At the lower end of the two vacuum arc extinguishing chambers Vi and V2 there are additional supports 34 attached to the respective insulating rails 23 and 31. The supports 34 also have a radial arm 35 with contact lamellae 26 connected to a contact ring 36 which is mounted on the inner surface of the insulating cylinder 28-29.

In phases Y and Z, the two halves of the insulating cylinder are attached to an upper disc 37 and a lower disc 38, which are respectively fixed to the upper insulating plate 1 and the lower insulating plate 2. To the two

6/8 discs 37 and 38 are supported upper carrier 39 and lower carrier 40 on the two insulating rails 31 of the auxiliary vacuum arc extinguishing chamber Ug. To the carriers 39 and 40, two carriers 41 and 42 are mounted on the rails 23 of the main vacuum arc extinguishing chamber Vi. Gear 11 is attached to neck 43 of carrier 40, and gear 12 is attached to neck 44 of carrier 42.

Plugs 46 are attached to the movable contact terminals 45 of the two vacuum arc extinguishing chambers Vi and Ug, to which is attached one end of a rocker 47, bearing in the middle of a vertical support 48 mounted to a support 34. At the outer end of the rocker 47 there is a roller 49, which contacts during switching with the front cam surface of a ring 50 attached to the insulating cylinder 28-29. The current removal from the carrier 34 to the terminal 45 is done by a flexible connection 51, and the connection between the terminals 45 of the two vacuum arc extinguishing chambers Vi and V2 is done by a flexible connection 52.

At the bottom of phase X there is also a lower disc 38, the bearing to which is the same as for phases Y and Z (Fig. 3). In this case, the variant is shown, in which the transmission of the movement between the three phases takes place through two large gears 7 and 8 and two large spur gears 9 and 10.

The insulating rails 23 of the main vacuum arc extinguishing chamber V1 are extended and at their upper end are gripped to the shaft 22 of the malt wheel 19. The used rails 31 of the auxiliary vacuum arc extinguishing chamber Ug are also gripped to the neck 53 of the malt wheel 20.

The system for guiding the two insulating rails 13 and 14 is mounted to the lower insulating plate 2. It is not shown because it is known and not complicated.

As noted at the beginning, the construction of the bearing head 4 with the mechanisms in it is known. What is new is the construction of the three phases X, Y, Z and their connection in one assembly unit with a horizontal arrangement (Fig. 1).

The action of the step regulator is as follows, d

The drive shaft 15 is rotated by a known motor drive, not shown. The worm gear 16 interacts with the known mechanism 17 and begins to tension the switching spring 18. At a precise moment, the potential energy in the spring 18 is released and a jump-like sequential rotation of the two Maltese wheels 19 and 20 follows.

7/8 in one step of 36°. First, the insulating rails 23 of the main vacuum arc extinguishing chamber Vi are switched and the contact lamellae 26 jump from the operating U-shaped contact element 30 to the adjacent one. In doing so, the roller 48 interacts with the face cam 50 and the main vacuum arc extinguishing chamber Vi opens so that the switching of the adjacent shaped contact element is de-current. At the end of the switch, Vi closes. An analogous switching of the auxiliary vacuum arc extinguishing chamber V2 follows, with which the process ends. Everything lasts on the order of several tens of milliseconds. Therefore, the resistors R, which are wound by a resistance wire, are loaded a little. Resistors R are attached to both sides of the insulating rails 23 and 31.

Claims (6)

PATENT CLAIMS 1. A step-down voltage regulator with a horizontal arrangement containing a carrying head with a spring energy accumulator and a two-stage Maltese gear, three single-phase power switches mounted horizontally in line with each other, each power switch having one main vacuum arc extinguishing chamber, one auxiliary vacuum arc extinguishing chamber and a resistor , characterized in that the three single-phase power switches (X, Y, Z) are arranged linearly horizontally next to each other with insulation distances provided between them and are fixed to an upper insulating plate (1) and a lower insulating plate (2), as the supporting structure of each power switch is composed of a vertical insulating cylinder cut into two halves (28, 29), an upper disk (37) and a lower disk (38), to which, by means of an upper arm (39) and a lower arm (40), are supported two insulating bars (31) carrying an auxiliary vacuum arc extinguishing chamber (V2), next to it is located a main vacuum arc extinguishing chamber (Vi) attached to two insulating rails (23) supported by an upper arm (41) and a lower arm (42) to the two arms (39, 40), each of the two vacuum arc extinguishing chambers (Vi and V2) having an upper support (24) and a lower support (34) which are mounted to the respective insulating rails (23, 31), the upper support (24) of the main vacuum arc extinguishing chamber (Vi) having a radial arm (25) with contact lamellae (26), the lower carrier (34) has a radial arm (35) with contact lamellas (26), and on the inner surface of the insulating cylinder (28, 29) in a horizontal plane, a certain number of U-shaped contact elements with a terminal (30) are mounted, to which contact the contact lamellae (26) of the radial arm (25) and identical contact lamellae (26) located on the radial arm (33) of a carrier (32) attached to the insulating rails (31) and isolated from the carrier (24) of the auxiliary vacuum arc extinguishing chamber (V2) and also the lower support (34) of the main vacuum arc extinguishing chamber (Vi) with the radial and an arm (35) with contact lamellae (26) is connected to a contact ring (36) mounted on the inner surface of the insulating cylinder (28, 29). 2. Horizontal step voltage regulator according to claim 1, characterized in that one of the three single-phase power switches (in the case X) is connected to a bearing head (4) containing a drive shaft (15) with a worm gear (16) ), a spring mechanism (17, 18) and two Maltese wheels (19, 20), wherein a Maltese wheel (19) is coupled to the insulating rails (23) of the main vacuum arc extinguishing chamber (Vi), and a Maltese wheel (20) is coupled with the insulating rails (31) of the auxiliary vacuum arc extinguishing chamber (V2). 3. Horizontal step voltage regulator according to claims 1 and 2, characterized in that a rocker arm (47) is mounted on a vertical support (48) mounted to a support (34), one end of which is connected to a fork ( 46) clamped to the movable contact terminal (45) of each of the two vacuum arc extinguishing chambers (Vi and V2), and at the other end of the rocker (48) there is a roller (49) which contacts during switching with the front cam surface of a ring (50) attached to the insulating cylinder (28, 29), the electrical connection between the carrier (34) and the terminal (45) being made by a flexible connection (51), and the connection between the terminals (45) of the two vacuum arc extinguishing chambers (Vι and V2) is through a flexible connection (52). 4. Step-down voltage regulator with horizontal arrangement according to claims 1, 2 and 3, characterized in that resistors (R) wound by a resistance wire are mounted on the sides of the four insulating rails (23 and 31) and are connected in series both of their terminals are connected to the carrier (24) of the auxiliary vacuum arc extinguishing chamber (V ₂ ) and the isolated carrier (32). 5. Step voltage regulator with a horizontal arrangement, according to claims 1, 2, 3 and 4, characterized in that the transmission and synchronization of the movement from the first single-phase power switch (X) to the other two (Y, Z) takes place through one a large gear (7) connected to a neck (43) of a carrier (40) and an identical gear (8) connected to a neck (44) of a carrier (42), these two gears (7, 8) being meshed with satellite gears (9 and 10) bearing on an axle (21) fixed to the lower insulating plate (2), and in this case the preferred option is that the ring gears of the four gears are injection molded from plastic. 6. Step voltage regulator with a horizontal arrangement, according to claims 1, 2, 3 and 4, characterized in that, as a variant, a small gear (11) is attached to the neck (43), a second one is attached to the neck (44) a small gear (12), and the drive of these gears of the three single-phase power switches (X, Y, Z) is carried out by two insulating racks (13, 14).