JPS6150367B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises one main winding for each phase and one fine adjustment winding with a tap on the selector arm for voltage regulation, placed on the same leg of the transformer. A changeover switch is connected to the beginning and end of the coarse adjustment winding by two outer contacts, and a center contact of the changeover switch is connected to the fine adjustment winding. and in a tap selector of a transformer in which the energized selector arm is connected to an auxiliary tap which can be coupled to the coarse adjustment winding whenever a change is made to change the potential of the fine adjustment winding. Concerning contact placement.

In contrast, German Patent Specification No. 960 303 discloses a plurality of selector arms, one of which is energized and connected to a tap of a so-called fine-tuning winding. It is known to provide this in a load tap changeover switch. Additionally, an auxiliary tap is provided which is coupled to the end of the transformer winding which is connected in series with the fine adjustment winding. The selector arm, which is energized when the reversing switch for the fine adjustment winding is switched, is then connected to this auxiliary tap. This reversing switch is likewise coupled on the one hand to the series-connected windings and on the other hand to the ends of the fine-tuning winding, so that the voltage of the fine-tuning winding is always in series depending on the position of the reversing switch. It is added to or subtracted from the voltage of the connected winding.

Additionally, West German patent application publication number 2358885
It is known to connect a so-called coarse adjustment winding in series with a fine adjustment winding, such that the starting end of the coarse adjustment winding is coupled to the main winding of the transformer. A changeover switch is provided for the coarse adjustment winding, the center contact of which is coupled 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 said publication no auxiliary tap is shown for the energized selector arm connected to the end of the coarse adjustment winding, but during actuation of the transfer switch belonging to the coarse adjustment winding. Said auxiliary tap must be provided to eliminate voltage jumps that occur.

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 object is achieved according to the invention in the above-mentioned tap selector, in which the central contact of the changeover switch is connected by its outer contacts to the central contact of a reversing switch which is connected to the beginning and end of the fine adjustment winding. , the transfer switch further has an outer contact coupled to a terminal end of the main winding, the terminal end of the main winding coupled to a central contact of a second transfer switch, and a An auxiliary changeover switch is provided whose outer contacts are likewise connected to the start and end of the coarse adjustment winding, and which has three outer contacts, the middle contact of which is connected to the auxiliary tap, and the outer contacts of which are connected to the auxiliary tap. coupled respectively to the ends of the main winding and to the beginning and end of the coarse adjustment winding, such that the contacts of all said changeover switches and of the reversing switches are arranged at mutually distinct levels of the tap selector; achieved by.

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 end 52 is connected to the outer contact 5 of the first changeover switch 53 and the second changeover switch 5.
4 as well as the outer contact 12 of the auxiliary changeover switch 55. The outer contacts 6 and 4 of the first changeover switch 53 and the outer contacts 1 and 2 of the second changeover switch 54 are both connected to the beginning 56 and the end 57 of the coarse adjustment winding 58.
Contacts 13 and 11 on the outside of the auxiliary changeover switch 55
Similarly, the start end 56 and end 57 of the coarse adjustment winding 58
is combined with The center contact 7 of the first changeover switch 53 is connected to the center contact 10 of the reversing switch 59, and the outer contacts 8 and 9 of the reversing switch 59
are connected to the beginning and end of the fine adjustment winding 60.
The central contact 14 of the auxiliary changeover switch 55 is connected to an auxiliary tap 24 which, together with the tap 61 of the fine adjustment winding 60, is also located in the region of the selector arm 62 of the on-load tap changeover switch 63. An on-load tap changeover switch 63 is connected to a phase conductor 64 adapted to receive the output voltage of the transformer.

In the contact positions shown in FIG. 1, the transformer is regulated in the highest voltage range. In this case, the voltage of the coarse adjustment winding 58 and the voltage of the portion of the fine adjustment winding 60 located above the selector arm are added to the voltage of the main winding 51. To reduce the voltage, the selector arm 62 is guided upward until the energized selector arm connects with the auxiliary tap 24.

FIG. 2 shows that in the exemplary embodiment, the second changeover switch 54, the first changeover switch 53 and the reversing switch 59 each have four connection positions and are operated by one common drive shaft 65. It is understood that they are forced to do so.

When the energized selection arm reaches the auxiliary tap 24, the drive shaft 65 is rotated by one adjustment position, and the first changeover switch 53 changes from contact 4 to contact 5.
can be switched to As a result, the voltage of the coarse adjustment winding 58 is no longer applied to the voltage of the phase conductor 64 and the energized selector arm can be switched to the lowest tap 61. However, this requires that the number of turns of the coarse adjustment winding 58 and the number of turns of the fine adjustment winding 60 be approximately equal.

At this point, only the voltage of the upper portion of the fine adjustment winding 60 is applied to the voltage of the main winding 51. This voltage is reduced again by moving the selector arm 62 upwards. During this time, the auxiliary changeover switch is operated and the outer contact 11
It is switched from to the outer contact 12. Therefore, the potential of the auxiliary tap 24 is approximately equal to the potential of the tap 61 of the fine adjustment winding adjacent thereto.

When the energized selector arm reaches the auxiliary tap 24 again, the drive shaft 65 performs a second action to switch the second changeover switch 54 from outer contact 1 to outer contact 2 and back again. Switch 59 is switched from outer contact 8 to outer contact 9. This switching of reversing switch 59 causes the voltage on the lower portion of fine adjustment winding 60 to be subtracted from the voltage on main winding 51 after the selector arm is switched further to the lowest tap 61. Contact 1 on the outside of the second changeover switch
Switching from to the outer contact 2 prepares for the reverse connection of the coarse adjustment winding 58. The switching of this second changeover switch can take place earlier or somewhat later than this point.

To further reduce the voltage, selector arm 62 is again
is guided upwards, at which point the auxiliary changeover switch 55 is switched from the outer contact 12 to the outer contact 13. As a result of the cooperation between this switching of the auxiliary changeover switch 55 and the switching of the second changeover switch 54, the potential of the auxiliary tap 24 becomes equal to the difference between the voltage of the main winding 51 and the voltage of the coarse adjustment winding 58. .
The energized selector arm 62 can now be connected to the auxiliary tap 24 again.

In this position of the energized selector arm, the final actuation of the drive shaft 65 takes place and the first changeover switch 53 is switched from the outer contact 5 to the outer contact 6. The coarse adjustment winding 58 is therefore also reversely connected, and after further switching of the selector arm the voltage on the phase conductor 64 changes from the voltage on the main winding 51 to the coarse adjustment winding 5.
8 minus the voltage at the lower portion of the fine adjustment winding 60.

It is therefore also possible by means of this connection circuit to selectively add the voltages of the two winding sections, namely the coarse adjuster wire and the fine adjuster winding, to the voltage of the main winding 51. It also becomes possible to subtract from the voltage on line 51. Therefore, in a given adjustment range of the voltage of the transformer, a small number of turns of coarse and fine adjustment windings are sufficient, and it is sufficient to provide approximately a quarter of the number of taps as the number of adjustment stages. It is.

This causes each level of the tap selector to represent only the potential difference along the coarse adjustment winding or the potential difference along the fine adjustment winding.
The sum of these potential differences never appears. Further, in the tap selector, the contacts of the first changeover switch 53 are arranged at a level located between the level at which the contacts of the second changeover switch are arranged and the level at which the contacts of the auxiliary changeover switch are arranged. If so, it is ensured that the sum of the potential difference along the coarse adjustment winding and the potential difference along the fine adjustment winding also does not appear between mutually adjacent levels of the tap selector. be done.

As explained above, this invention consists of a main winding for each phase, a fine adjustment winding having a tap for a selector arm for voltage adjustment, and a coarse adjustment winding disposed on the same leg of the transformer. It is equipped with a line and a changeover switch.
It is connected to the start and end of the coarse adjustment winding by the outer contacts of the changeover switch, and the center contact of this changeover switch is connected to the fine adjustment winding, and is also used for changing the potential of the fine adjustment winding. In transformer tap selectors, which are provided with auxiliary taps connectable to the coarse adjustment winding, to which the selector arm, which is energized in each case, connects when a changeover takes place, the central contact of the changeover switch is connected to its outer side. The changeover switch further has outer contacts connected to the ends of the main winding, and the changeover switch further has outer contacts connected to the ends of the main winding. The ends of the windings are connected to the central contacts of a second transfer switch, the outer contacts of which are likewise connected to the beginning and end of the coarse adjustment winding, and three outer contacts. An auxiliary changeover switch is provided having a central contact connected to the auxiliary tap and its outer contacts connected respectively to the end of the main winding and to the start and end of the coarse adjustment winding, and having all of the foregoing. By arranging the contacts of the change-over switch as well as the reversing switch at mutually distinct levels of the tap selector, the voltage adjustment range of the transformer in question is kept the same while the windings between the change-over switch contacts are reduced. Decrease the number of wire turns and the number of turns of fine adjustment winding,
As a result, when a surge voltage occurs, the stress caused by the surge voltage between the contacts is reduced.

[Brief explanation of the drawing]

FIG. 1 shows the connection circuit of the tap selector of the invention, and FIG. 2 shows the contact arrangement of the invention at separate levels of the same tap selector. 1, 2, 4, 5, 6, 11, 12, 13... contact on the outside of the changeover switch, 3, 7, 14... contact in the center of the changeover switch, 8, 9... contact on the outside of the reversing switch, 14...Center contact of reversing switch, 24...Auxiliary tap, 51...Main winding, 52
... end of main winding, 53 ... first changeover switch, 54 ... second changeover switch, 55 ... auxiliary changeover switch, 56 ... starting end of coarse adjustment winding, 57
... End of coarse adjustment winding, 58 ... Coarse adjustment winding, 5
9...Reverse switch, 60...Fine adjustment winding.

Claims (1)

[Scope of Claims] 1. One main winding for each phase and one fine adjustment winding with a tap on the selector arm for voltage regulation and a coarse winding located on the same leg of the transformer. an adjustment winding, a changeover switch is connected to the starting end and the end of the coarse adjustment winding by two outer contacts, and a central contact of the changeover switch is coupled to the fine adjustment winding; In tap selectors of transformers, the selector arm, which is energized each time a change is made to change the potential of the fine-tuning winding, is connected to an auxiliary tap that can be coupled to the coarse-tuning winding. The center contact of the reversing switch is connected by its outer contacts to the center contact of a reversing switch connected to the beginning and end of the fine adjustment winding, and the changeover switch is further connected to the outer end of the main winding. has a contact point,
The ends of this main winding are connected to the center contacts of a second transfer switch, and the outer contacts of this second transfer switch are likewise connected to the beginning and end of a coarse adjustment winding, and three An auxiliary changeover switch having outer contacts is provided, the central contact of which is connected to the auxiliary tap and the outer contacts of which are respectively connected to the end of the main winding and the start and end of the set adjustment winding, and Contact arrangement in a tap selector, characterized in that the contacts of all changeover switches as well as reversing switches are arranged on mutually separate levels of the tap selector. 2. In the device according to claim 1,
The contact point of the first changeover switch coupled to the center contact point of the reversing switch is located at a level between the level at which the contact point of the second changeover switch is located and the level at which the reversing switch is located. Contact arrangement of tap changer.