JPS6148766B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises one main winding for each phase, one fine adjustment winding with taps on the selector arm for voltage regulation, and a at least two coarse adjustment windings disposed in the section, the fine adjustment winding being connected to the intermediate contact of the transfer switch, and the outer contact of the transfer switch being coupled to the terminal end of the coarse adjustment winding. and an auxiliary tap is connected to the end of the coarse adjustment winding adjacent to the fine adjustment winding;
The result is a connection point arrangement in a transformer tap selector in which the energized arm of the selector connects to the auxiliary tap when the changeover switch of the coarse adjustment winding changes.

According to West German Patent Specification No. 960303, a plurality of selector arms are provided on a load tap changeover switch,
It is known in which one of the selector arms is always energized and connected to a tap of a so-called fine adjustment winding. Additionally, in this configuration, an auxiliary tap is coupled to the end of the transformer winding which is connected in series with the fine adjustment winding. When the changeover switch for the fine adjustment winding is switched, the energization selector arm is connected to this auxiliary tap. This change-over switch is likewise coupled on the one hand to the series-connected windings and on the other hand to the ends of the fine-adjustment winding, so that the voltage of the fine-adjustment winding is always connected in series depending on the contact position of the change-over switch. It is added or subtracted from the voltage of the winding connected to the

Additionally, West German patent application publication number 2358885
According to No. 1, a so-called coarse adjustment winding is connected in series with a fine adjustment winding, and the starting end of the coarse adjustment winding is coupled to the main winding of a transformer. A changeover switch is provided for the coarse adjustment winding, the intermediate point of which is connected to the beginning of the fine adjustment winding, and the outer contacts of which are connected to the beginning and end of the coarse adjustment winding, respectively. Therefore, depending on the position of the changeover switch, the voltage of the coarse adjustment winding is added or not to the voltages of the main winding and the fine adjustment winding. In this publication no auxiliary tap is shown for the energized selector arm coupled to the end of the coarse adjustment winding, but during actuation of the transfer switch located in the coarse adjustment winding. Said auxiliary tap must be provided in order to eliminate voltage jumps occurring in the circuit.

An object of the present invention is to reduce the number of turns of the winding between the contacts of the changeover switch and the number of turns of the fine adjustment winding while maintaining the voltage adjustment range of the transformer the same. It is an object of the present invention to provide a connection circuit in which stress caused by a surge voltage between contacts is reduced when a surge voltage is generated.

This purpose is to provide a tap selector for a transformer according to the present invention, in which a plurality of coarse adjustment windings are each provided with a changeover switch, and the starting end of each coarse adjustment winding is connected to the coarse adjustment winding connected in series immediately before it. two coarse adjustment windings connected to the intermediate junction of the transfer switch to the line, and auxiliary transfer switches are provided, the outer contacts of the first of which are connected in series immediately after the transformer main winding. one of the outer contacts of the immediately following auxiliary changeover switch is connected to the end of the line, and the other is connected in series immediately after the coarse adjustment winding. connected respectively to the ends of the adjustment windings, the intermediate contacts of the last auxiliary changeover switch being coupled to the auxiliary taps, and further such that the contacts of the changeover switch for each coarse adjustment winding are arranged at mutually distinct levels. achieved by.

In the above configuration of the present invention, the first auxiliary changeover switch, the immediately following auxiliary changeover switch, and the last auxiliary changeover switch may be a single auxiliary changeover switch, or the two auxiliary changeover switches described below may be a single auxiliary changeover switch. They may be the same auxiliary changeover switch.

Next, details of the present invention will be explained based on embodiments shown in the drawings.

In Figure 1, the main winding 5 is connected to the neutral point 50 of the transformer.
1 is connected, and its winding end 52 is connected to the winding start end 53 of the first coarse adjustment winding 54. A changeover switch 55 attached to the coarse adjustment winding 54 is connected at its outer contact 1 to a starting end 53 of the coarse adjustment winding 54 and at its outer contact 2 to an end 56 of the coarse adjustment winding. The intermediate junction 3 of the changeover switch 55 is connected to the starting end 57 of the second coarse adjustment winding 58 . A changeover switch 59 is attached to this second coarse adjustment winding, and its outer contact 4 is connected to the starting end 57 of the coarse adjustment winding 58.
Also, the outer contact 5 is coupled to the end of the coarse adjustment winding 58. Also, the intermediate point 6 of the changeover switch 59
is coupled to the starting end 61 of the fine adjustment winding 62.

The fine adjustment winding 62 is provided with taps 63 on which a selector arm 64 contacts. Either one of the selector arms is energized depending on the position of the on-load tap changeover switch 65 attached thereto. From the on-load tap changeover switch 65, the output conductor 66 of the relevant phase of the transformer is connected.
is brought out.

Furthermore, an auxiliary changeover switch 67 is provided, the outer contacts 7 of which are connected to the end 56 of the coarse adjustment winding 54, and the outer contacts 8 of which are connected to the end 60 of the coarse adjustment winding 58. Further, the intermediate junction 9 of the auxiliary changeover switch 67 is connected to the auxiliary tap 24. When either the selector switch 55 or 59 is switched, the selector arm 6 which is energized
4 is connected to the auxiliary tap.

In the illustrated contact state, the voltage in coarse windings 54 and 58 is applied to the voltage in the portion of fine winding 62 above the energized selector arm. To reduce the voltage from this state, the energized selector arm 64 is connected to the auxiliary tap 24, and the changeover switch 59 connects the intermediate contact 6 to the outer contact 4. This disconnects the coarse adjustment winding 58 and allows the energized selector arm to be connected to the lower tap 63. On the other hand, in order to avoid large voltage steps in this case, it goes without saying that the numbers of turns in the coarse and fine adjustment windings must be selected to be relatively equal.
While the energized selector arm is in contact with one of the taps 63, the auxiliary changeover switch 67 is switched so that its intermediate contact 9 is coupled to the outer contact 7. If the voltage is then to be further reduced, the energized selector arm 64 is again connected to the auxiliary tap 24 and the changeover switch 55 is switched from the outer contact 2 to the outer contact 1.

It is advantageous for the connecting arms of the changeover switches 55 and 59 to be driven by a common shaft for operating the changeover switches. Since the contacts of these changeover switches are located on two mutually parallel levels, there is therefore only a voltage difference at one level corresponding to the number of turns of the coarse adjustment winding 54 or 58 belonging to the changeover switch. It just appears. If the changeover switches 55 and 59 are operated in common, each of these changeover switches has three connection positions, the two outer contacts, which are always labeled with the same number, being connected to one another. As a result, the circuit sequence described above with reference to FIG. 1 is obtained. Since the changeover switches 55 and 59 and the auxiliary changeover switch 67 must always be connected alternately, the auxiliary changeover switch 67 is preferably driven by a separate drive shaft.

FIG. 2 schematically shows a contact configuration belonging to the configuration shown in FIG.

FIG. 3 is an extension of the circuit of FIG. 1, i.e.
An arrangement is shown in which three coarse adjustment windings each having one changeover switch are provided, and FIG. 4 shows a contact arrangement belonging to this arrangement. In this case, the intermediate point 12 of the changeover switch 59 is connected to the starting end of the third coarse adjustment winding 68, and the intermediate point 12 of the changeover switch 69
is coupled to the starting end 61 of the fine adjustment winding 62. The added auxiliary changeover switch 70 is connected by its outer contact 13 to the intermediate contact 9 of the auxiliary changeover switch 67.
and is coupled by its outer contacts 14 to the ends of the coarse adjustment windings 68. Auxiliary changeover switch 7
The intermediate node 15 of 0 is connected to the auxiliary tap 24. The operating method in this case is the same as that in FIG. As shown in FIG. 4, two auxiliary changeover switches 67 and 70 and changeover switches 55, 5
9 and 69 can likewise be driven by a common drive shaft.

As explained above, the present invention includes one main winding for each phase, one fine adjustment winding with a tap on the selector arm for voltage regulation, and one fine adjustment winding on the same leg of the transformer. at least one coarse adjustment winding disposed in the arrangement, the fine adjustment winding being connected to the intermediate contact of the transfer switch, and the outer contact of the transfer switch being coupled to the terminal end of the coarse adjustment winding. and an auxiliary tap is connected to the end of the coarse adjustment winding adjacent to the fine adjustment winding, so that when the transfer switch of said coarse adjustment winding is toggled, an energized selector arm is connected to said auxiliary tap. In the contact arrangement of the tap selector for a transformer, a plurality of coarse adjustment windings are each provided with a changeover switch, and the starting end of each coarse adjustment winding is connected to the coarse adjustment winding connected in series immediately before it. and auxiliary changeover switches are provided, the outer contacts of the first of which are connected in series immediately after the transformer main winding. , one of the outer contacts of the immediately following auxiliary changeover switch is connected to the intermediate contact of the preceding auxiliary changeover switch, and the other is connected in series immediately after the coarse adjustment winding. are respectively connected to the ends of the windings, so that the intermediate contact of the last auxiliary changeover switch is coupled to the auxiliary tap, and furthermore the contacts of the changeover switch for each coarse adjustment winding are arranged at mutually distinct levels. By this, the number of turns of the winding between the contacts of the transfer switch and the number of turns of the fine adjustment winding are reduced while keeping the voltage adjustment range of the transformer the same, so that in the event of a surge voltage, the surge between the contacts is reduced. This has the effect of reducing stress caused by voltage.

[Brief explanation of the drawing]

FIG. 1 schematically represents the connection of a transformer tap changer according to the invention with two coarse adjustment windings, and FIG. 2 schematically represents the contact arrangement of the tap selector of FIG. 1. Furthermore, FIGS. 3 and 4 schematically represent the connection and contact arrangement of a tap changer according to the present invention when three coarse adjustment windings are provided. 1, 2, 4, 5, 7, 8, 10, 11, 13,
14... Contacts on the outside of the changeover switch, 3, 6,
9, 12, 15...Intermediate point of changeover switch, 2
4...Auxiliary tap, 51...Main winding, 52,5
6, 60... Winding end, 53, 57, 61... Winding start end, 54, 58, 68... Coarse adjustment winding, 5
5, 59, 69...Selector switch, 62...Fine adjustment winding, 63...Tap, 64...Selection arm, 6
7, 70...Auxiliary changeover switch.

Claims (1)

Claims: 1. One main winding for each phase and one fine adjustment winding with a tap on the selection arm for voltage regulation and at least two windings arranged on the same leg of the transformer. coarse adjustment windings, the fine adjustment windings being connected to intermediate contacts of the changeover switch, and the outer contacts of the changeover switch being coupled to the ends of the coarse adjustment windings; a transformer connected to the end of the adjustment winding adjacent to the fine adjustment winding so that when the transfer switch of said coarse adjustment winding is toggled, the energized arm of the selector connects to said auxiliary tap; In the contact arrangement of the dexterous tap selector, a changeover switch is provided for each of the plurality of coarse adjustment windings, and the starting end of each coarse adjustment winding is connected to the intermediate junction of the changeover switch for the coarse adjustment winding connected in series immediately before it. and auxiliary transfer switches are provided, the outer contacts of the first of which are connected to the ends of two coarse adjustment windings connected in series immediately after the transformer main winding, and One of the outer contacts of the immediately succeeding auxiliary changeover switch is connected to the intermediate contact of the preceding auxiliary changeover switch, and the other is connected to the terminal end of the coarse adjustment winding connected in series immediately after the coarse adjustment winding. A contact arrangement in a tap selector, characterized in that the intermediate contact of the last auxiliary changeover switch is connected to the auxiliary tap, and that the contacts of the changeover switch for each coarse adjustment winding are arranged at mutually distinct levels. 2. In the device according to claim 1,
A contact arrangement in a tap selector, characterized in that a common drive shaft is provided for each of the changeover switch group and the auxiliary switch group.