DE542275C - Switching method for voltage regulation, in particular for the generation of adjustable additional voltages with secondary windings of a fixed and an adjustable additional transformer in the line - Google Patents

Description

GERMAN EMPIRE

ISSUED ON
JANUARY 22, 1932

REICH PATENT OFFICE

PATENT LETTERING

CLASS 21 d ² GROUP

Koch & Sterzel A.-G. in Dresden*)

and an adjustable additional transformer

Patented in the German Empire on July 15, 1930

With the known combinations of a regular and a fixed additional trans- ' formator, the secondary winding of the adjustable additional transformer is switched over, which is why the switches are dimensioned not only for the normal current flowing through, but also for the short-circuit current must be. When connecting several transformers in series, their secondary windings lie one behind the other in the cable run and their primary coils are connected in parallel or in series and from one shared network, the primary switch cannot be easily switched open, because through the current flowing in the cable, like an ordinary one Measuring current transformer with the secondary terminal open, one corresponding to the primary current secondary voltage is induced.

Such changeover switches must with the aid of appropriate bridging resistors be designed so that these dangerous, backward induced secondary voltages do no harm, which requires a complicated switch.

The present invention is when combining a fixed and a controllable Additional transformer, the occurrence of the backward induced voltages in the switch-off or switchover position Made harmless that the parallel connection lines between the two additional transformers remain in place even when the changeover switch is switched off, so that the now in the two primary coils of the flowing through Mains current reverse induced voltages of the same magnitude and direction through the parallel connection lines be short-circuited.

In the figures, exemplary embodiments according to the invention are shown.

11 means the fixed and 12 den adjustable additional transformer with positive and negative regulation range. The one on the cable run lying secondary windings of the two transformers are connected in series and the primary windings parallel to each other via the switch 13 to the network placed.

The mode of action is as follows:

If the network is to be _{regulated by + 10 ° / 0} so that the total regulating power is 20 ° / ₀ , this corresponds to 100 ° / "additional power. The fixed additional transformer 11 becomes equal to _{1/4 of the regulating power for 5 ° / 0} and thus for 25 ° / ₀ additional power and

*) The patent seeker stated as the inventor:

Viktor Dunkel in Dresden.

the adjustable additional transformer 12 for + S ° / o regulating power or + 25 ° / ₀ additional power or converted for 10 ° / ₀ regulating power corresponding to 50 ° / ₀ additional power. This additional tension, which can be regulated by + 25 ° / _{0, is} added to the fixed additional tension of 25 ° / o ^so that it can be regulated from zero to 50 ° / ".

In the switch position shown, the fixed additional transformer would result in an additional voltage of 25 "/" and with the regulating transformer an additional voltage of zero to 50 ° / _{0 in} total. 25 °. / ₀ , the additional voltages cancel each other out. The total additional voltage is thus zero. The current directions are indicated by the solid arrows. If the pole reverser 13 is now opened, the transformers 11 and 12 lack the previous primary supply, and they are now both as current transformers in the cable run, and their secondary windings have become primary windings, which now induce the former primary as secondary windings, whereby the level of the voltage would depend on the current flowing through it, if not the current in the primary, now secondary winding of the transformer 11 reverse its \ '* sign by the flowing line current would. This reversal also reverses the direction in the secondary winding of the additional transformer 11, so that voltages of the same magnitude and direction (dotted arrows) are induced in the former primary coils on both sides, which are short-circuited via the still existing parallel connecting lines, so that both apparatuses how secondary short-circuited current transformers are in the cable run. When switching to the minus regulation, the changeover switch 13 is switched to the other side, whereby the primary coils are again fed from the mains, but with the opposite sign. The additional voltage of the transformer 11 is now - 25 ° / ₀ and that of the regulating transformer -j- 25 ° / o · If the thrust transformer is regulated from +25 to zero to -25, the result is an additional voltage of - · 50 ° / o ·

In the case of thrust transformers, the winding in the cable run is housed in slots and consequently cannot easily for any tension against the iron core to be isolated. This is why this winding located in the slots is made with the iron core 17 connected and the iron core within the vessel or the whole vessel for the voltage in question is isolated from earth, as indicated in Fig. 2 by the insulator 18 should be, and dimensioned the movable winding with the yokes for the corresponding voltage. Is also for this Winding the operating voltage uncomfortable, it can be via an intermediate transformer be fed.

In Fig. 3 also shows an embodiment in which the additional service of the thrust transformer 12 via an intermediate transformer 15 (series transformer) is transferred to the cable run, which may be in the case of very high additional voltages or very strong line currents is appropriate for the construction of the thrust transformer.

In Fig. 4 an embodiment is shown in which the adjustable additional transformer 12 through a fine-stage regulating transformer is formed, which in turn via an intermediate transformer 16 in the to regulating network so that there are no switching contacts in the cable run itself.

If a thrust transformer is arranged, the yokes that go up and down can of the iron core also for the inevitable control of the switch 13 in use known pressure or tension transmissions can be used.

Claims (8)

Patent claims: 1. Switching method for voltage regulation, especially for generation adjustable additional voltages with secondary windings of a fixed and an adjustable additional transformer in the cable run, characterized in that the primary windings are parallel to one another for generating additional voltages switched to the mains, then to generate the total additional voltage NuU. are disconnected from the network, so that the parallel connection lines are short-circuited in themselves and the supply lines to generate the opposite additional voltages polarity of the primary windings is reversed. 2. Device for performing the switching method according to claim 1, characterized characterized in that it consists of a double-pole changeover switch connected on the one hand to the network and on the other hand with the parallel-connected primary windings of the fixed and controllable Additional transformer is connected. 3. Device according to claim 1 and 2, characterized by the use a thrust transformer as a controllable additional transformer. 4 device according to claims ι to 3, characterized in that at high voltage the secondary winding of the thrust transformer is insulated with one erected iron core is connected. 5. Device according to claim 4, characterized in that the thrust transformer is primarily fed via an intermediate transformer. 6. Device according to claim 1 to 3, characterized in that the thrust transformer The network is regulated via an intermediate transformer and, if necessary, primarily via an intermediate transformer is fed. 7. Device according to claim 1 to 6, characterized in that the changeover switch is inevitably controlled by the thrust transformer. 8. Device according to claim 1, 2 and 4 to 7, characterized in that as adjustable additional transformer a finely stepped step transformer is used. 1 sheet of drawings