WO2013092111A1

WO2013092111A1 - Drive unit for on-load tap changer

Info

Publication number: WO2013092111A1
Application number: PCT/EP2012/073474
Authority: WO
Inventors: Gudrun Diepold; Andreas FREISBERG; Christian Hurm; Marcus Lenz; Maximilian NIEBLER; Michael Schmeisser; Franz WALDMANN; Eduard ZERR
Original assignee: Maschinenfabrik Reinhausen Gmbh
Priority date: 2011-12-22
Filing date: 2012-11-23
Publication date: 2013-06-27
Also published as: DE202011109470U1

Abstract

The invention relates to a drive unit for an on-load tap changer for actuating switching contacts. The drive unit comprises a housing, an electrical coil and an armature. The armature, which is connected to a switching contact, is in this case surrounded by the coil, which is connected to the housing. The armature is also arranged movably along an axis of symmetry. By applying an electrical voltage to the coil, the switching contact is actuated.

Description

Drive unit for Stufenschaiter

The invention relates to a drive unit for a tap changer for actuating switch contacts.

As is known from DE19816543C2, motor drives are usually used to operate on-load tap-changers. Despite the interaction of motor drive and

Tap changers are arranged spatially separated. The on-load tap-changer itself is recessed into the transformer tank, with the exception of the top-standing tap-changer head, while the motor drive is outside the transformer, usually at the transformer

Outside wall, is arranged. The connection between motor drive and tap changer is made via a wave train, which consists of individual shafts, couplings and joints. Also from Figure 1 of DE101 19664A1 is the general principle of the operation of the

Tap changer known by a motor drive. The outside of the transformer housing arranged motor drive actuates the tap changer via drive shafts. The motor drive is controlled by means of a voltage regulator, which determines the control commands by constantly comparing the actual and nominal voltages on the transformer.

DE4214431 C3 also discloses a tapped transformer, which by means of a

Tap changer and a drive motor is beschältet. The tap changer and the drive motor are connected to each other via drive shafts and a load gearbox. Another gear, which is attached to a drive shaft, determined by means of a position sensor, the position of the tap changer and passes it to the controller. The control in turn is responsible for the drive motor and determined by the

Switchover.

A major disadvantage of the known from the prior art drive units is the load and control gears used. The connection of these individual gears with each other is complex and time consuming and costly. The use of simple three-phase motors as drive means brings disadvantages. So it is very difficult and costly especially to obtain three-phase motors with constant Leistungsseckdaten. The inhomogeneity of the parameters of the three-phase motors requires additional sensors or customized gearboxes. Also, the wave trains are a major source of error. The couplings, which serve to connect the shafts with each other, wear out over time and can not guarantee a safe and reliable operation. Low game of individual parts adds up over the entire drive train and forms at the end, namely the tap changer, large deviations.

The object of the invention is thus to provide a drive unit for a tap changer, which is arranged closer to the tap changer, a fast and safe

Ensured actuation of the tap changer and can be realized easily and inexpensively.

The object is achieved by a drive unit for tap changer, which consists of a solenoid arranged directly on the switching contact, which opens or closes the switching contact by applying a voltage.

Although it is known from EP2312605A1 a breaker (a so-called. "Circuit Breaker"), which consists of a magnetic actuator and an actuatable by him vacuum interrupter, this embodiment is unsuitable for tap changer.

The invention will be explained below with reference to figures.

Show it:

Fig. 1 is a drive unit for a tap changer

Fig. 2 shows an embodiment of the drive unit with two coils

Fig. 3 two series-connected drive units

Fig. 4 shows a special interconnection of drive units

Fig. 5 is a drive unit with a coupling element

6 shows a drive unit with an indirect actuation of a switching contact via a link

Fig. 7 shows a drive unit with an indirect actuation of a switching contact via a rack and a cam.

In Fig. 1, a drive unit (1) for a tap changer with a housing (2), a first coil (3) and an armature (4) is shown. The first coil (3) is fixedly mounted in the housing (2) and is electrically conductively connected to a voltage source, not shown here. The armature (4) is arranged in the housing (2) such that it is at least partially surrounded by the first coil (3). In the housing (2) has a guide means (5) is mounted in the form of a bolt. Other embodiments of the guide means, such as tongue and groove connection, a plurality of bolts, etc. are conceivable. The armature (4) is additionally mechanical at one end via a connecting piece (6) with a switching contact (7) connected. About the connector (6), the switching contact (7) can be closed or opened. The switching contact (7) can be realized for example by a vacuum interrupter, a mechanical contact or the like. The actuation of a plurality of switching contacts (7) by means of a drive unit (1) is possible. For this purpose, the connecting piece (6) to the respective number of actuated

Switching contacts (7) can be adjusted.

By applying a voltage to the first coil (3) causes the resulting induction, a force by means of which the armature (4) is set in motion. The direction of movement of the armature (4) depends on the direction of the current flow and is linear along an axis of symmetry (8). The movement of the armature (4) thus leads to an opening or

Close the switching contact (7). Fig. 2 shows a possible embodiment of the drive unit (1) for tap changer, in which the armature (4) at least partially surrounding the first coil (3) is not fixed in the housing (2), but at least from a second coil (9) partially surrounded. The first coil (3) and the second coil (9) are mechanically connected to each other. The first coil (3) can thereby be used as an anchor and also perform a linear movement along the axis of symmetry (8). This is necessary above all when the force of the first coil (3) is insufficient to open the switching contact (7). Also in this embodiment, guide means for the armature (4) and the first coil (3) can be provided. 3 shows a further embodiment of the invention in which a first drive unit (1 .1) is arranged behind a second drive unit (1.2) and both actuate a switching contact (7). Both drive units (1.1, 1 .2) have different characteristic values with regard to the lifting height and / or the lifting force, but function according to the same principle as the drive unit (1) from FIG. 1. By means of this advantageous embodiment, different phases of an opening or closing operation can be achieved Closing operation can be controlled.

In Fig. 4, a further Verschaltungsmöglichkeit the drive unit (1) is shown. Each switching contact (7a, 7b, 7c, 7d) is connected to a separate drive unit (1 a, 1 b, 1 c, 1 d). In addition, all drive units (1 a, 1 b, 1 c, 1 d) are connected to a further, significantly larger drive unit (10). The drive unit (10) should above all be used as a support and used for example in welded switch contacts; So as a kind of security element.

In the embodiment shown in Fig. 5, a coupling element (1 1) is arranged between the drive unit (1) and the switching contact (7). This works according to the impact principle and is especially for loosening glued or welded

Switching contacts (7) suitable. In this case, the drive unit (1) via a coupling plunger (12), the coupling (1 1) and via the connecting piece (6) to the switching contact (7) mechanically connected. When the drive unit (1) is actuated, the movement is transmitted to the coupling ram (12). Since this has a freewheel, it is initially not yet to actuate the switching contact (7). At the end of the freewheel, a pulse is generated by the sudden resistance. This is transmitted to the switching contact (7) and dissolves the welded and glued locations in the switching contact (7). Depending on the size of the freewheel, the pulse strength can be varied.

Fig. 6 shows a further embodiment of the invention. Here are drive unit (1) and switching contact (7) indirectly via a link (13) mechanically in communication. The connecting piece (6) has at the upper end a cam (14) which scans the contour of the link (13) and thus actuates the switching contact (7). The link (13) is also mechanically connected via a connecting element (15) with the drive unit (1). By actuating the drive unit (1), the link (13) is moved via the connecting element (15). About the contour of the slide (13) and the cam (14) of the switching contact (7) by the connecting piece (6) is actuated. FIG. 7 shows a further embodiment in which the drive unit (1) actuates a toothed rack (16). This is mechanically connected to a gear (17) and thus converts the linear movement of the rack (16) in a rotational movement. The gear (17) is also connected to a cam (18) which actuates by rotation the switching contact (7) via the connecting piece (6).

A particular advantage of the invention is that the individual drives can be actuated independently of one another and thereby complex switching sequences can be realized. Also positive is the omission of the many gears and the waves. The simplified design and the no longer required items simplify production and reduce costs. The effects of the wear of individual parts also lose due to the reduction of the Drive unit on a few components in importance. The replacement of defective or worn components can be faster and more targeted.

Reference numeral 1 drive unit

1.1 first drive unit

1.2 second drive unit

1 a, 1 b, 1 c, 1 d drive unit

2 housings

3 first coil

4 anchors

5 guiding means

6 connector

7 switching contact

7a, 7b, 7c, 7d switching contact

8 symmetry axis

9 Second coil

10 drive unit

1 1 coupling element

12 coupling rams

13 scenery

14 cam

15 connecting element

16 rack

17 gear

18 cam

Claims

claims

1. Drive unit for a tap changer for actuating at least one

Switch contact,

characterized,

the drive unit {1} consists of a housing (2), an electrical coil (3) and an armature (4),

that the armature (4) is at least partially surrounded by the coil (3),

the coil (3) is mechanically connected to the housing (2),

that the armature (4) is mechanically connected to the at least one switching contact (7),

in that the armature (4) is movably arranged along an axis of symmetry (8) and that the coil (3) for the actuation of the at least one switching contact (7) is temporarily exposed to electrical voltage.

2. Drive unit for a tap changer for actuating at least one

Switching contact according to claim 1,

characterized,

that the coil (3) is at least partially surrounded by a second coil (9), that the coil (3) is mechanically connected to the second coil (9) and

the coil (3) is arranged to be movable along the axis of symmetry (8).

3. Drive unit for a tap changer for actuating at least one

Switching contact according to one of claims 1 or 2,

characterized,

in that at least two drive units (1.1, 1.2) are connected in series with the switching contact (7).

4. Drive unit for a tap changer for actuating at least one

Switching contact according to claim 3,

characterized,

a plurality of separate drive units (1 a, 1 b, 1 c, 1 d) each having a switching contact (7a, 7b, 7c, 7d) connected in parallel and can be actuated simultaneously by a larger common drive unit (10). Drive unit for a tap changer for actuating at least one

Switching contact according to one of claims 1 to 4,

characterized,

that between a drive unit (1) and the at least one switching contact (7) at least one coupling element (1 1) is arranged, and

that the coupling element (11) works according to the Schfagprinzip.

Drive unit for a tap changer for actuating at least one

Switching contact according to one of Claims 1 to 5,

characterized,

the drive unit (1) actuates at least one switching contact (7) indirectly via a link (13).

Drive unit for a tap changer for actuating at least one

Switching contacts according to one of Claims 1 to 6,

characterized,

the drive unit (1) actuates a toothed rack (16) which is mechanically connected to a toothed wheel (17),

that the gear (17) is mechanically connected to the cam (18) and

in that the cam (18) has at least one switching contact (7) directly or via a

Connecting piece (6) actuated.

Drive unit for a tap changer for actuating at least one

Switching contact according to one of the preceding claims,

characterized,

that the at least one switching contact (7) is a vacuum interrupter or a

mechanical contact is.

Drive unit for a tap changer for actuating at least one

Switching contact according to claim 8,

characterized,

that several vacuum interrupters to a single switching contact (7)

are summarized.