DE9319889U1 - Series circuit transformer - Google Patents

Description

93G 3 7 05.OE

Siemens AG

Series circuit transformer
5

The invention relates to a series circuit transformer, in particular for use in an airport lighting system, with a primary winding and at least one secondary winding, preferably several similar windings.

Series circuit transformers are known from the state of the art. They often have several secondary windings in which predetermined voltage levels are induced according to the number of windings. The secondary windings can have the same or different numbers of windings to generate the same or different voltages.

Especially for airport lighting systems, transformers with similar secondary windings are required, with which groups of lighting elements must be operated with a constant current. The voltage levels are in the order of magnitude between 100 V and 5000 V and more, which is medium voltage. If exact knowledge of the voltage is required, separate voltage transformers are used for the measurement. This always requires special effort, as partial discharge tests must also be carried out for the voltage transformers.

The object of the invention is to simplify a series circuit transformer of the type mentioned at the beginning with means for measuring voltage.

The object is achieved according to the invention in that in addition to the secondary winding, an auxiliary winding is provided as a secondary
Voltage converter is provided.

936 3705EN

This secondary voltage converter can preferably serve as a voltage sensor and be standardized according to the voltages occurring in the series circuit. For this purpose, additional units for signal processing and/or display can be connected downstream of the voltage converter. In particular, further digital processing is also possible via an AD converter.

The invention makes it possible to use suitable insulation to mount the voltage transformer on the secondary side of the normal series circuit transformer without having to make any structural changes. Compared to the state of the art with separate voltage transformers, the primary winding and the dynamo sheet can be dispensed with. This is particularly advantageous for voltages at medium voltage level (- or > 3 kV), as the state of the art requires a considerable amount of mechanical effort and space. This reduces the construction and assembly costs considerably.

Further details and advantages of the invention emerge from the following description of an embodiment.
Figure 1 shows a transformer with integrated voltage converter and

Figure 2 shows the application of a series circuit transformer in an airport lighting system.

In the figure, 1 denotes the primary side of a standard transformer with a winding 5, which is connected to the mains voltage and has the potentials 0 or U^ at its connections. 10 denotes the secondary side of the transformer, with a metal yoke 2 with dynamo sheets arranged between the primary side 1 and the secondary side 10. On the secondary side 10 there are one or more windings with taps for the series circuit voltage.

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93G 3705DE

For example, windings 11, 12, 13 with terminals 111 to 113, 121 to 123 and 131 to 133.

A transformer 1, 2, 10 shown in this way can be used, for example, in an airport lighting system, where it is important that groups of lighting elements in the secondary series circuit are operated with a constant current. In some applications, voltage measurement is also necessary. In the current state of the art, the series circuit voltage is recorded using separate, well-insulated measuring voltage converters.

It is now provided that an auxiliary winding 15 as a secondary voltage converter is applied directly to the secondary of the series circuit transformer with suitable insulation, so that it is potential-free from the windings 11 to 13. Galvanic decoupling can be carried out directly by means of such insulation 16, without the need for an additional primary winding or a dynamo sheet 0, as is the case with the prior art.

The secondary voltage transformer 15 is wound like a measuring transformer, the load of which remains stable regardless of the voltage. Known units for signal processing and/or display can be connected to the voltage transformer 15 defined in this way with connections 151 and 152. The displayed voltage is not identical to the voltage in the series circuit, but it is in a sense an image of the series circuit voltage. By appropriate standardization, an analog display can be made, for example.

The secondary voltage converter 15 can be designed in such a way that an A/D converter 20 can be connected directly to its terminals 151 and 152. In this case, the voltage signals can be further processed digitally and fed back as data transmission or for a control circuit.

938 3 7 O 5 OE

This enables cost-effective data transmission.

When using the series circuit transformer described in detail in Figure 1 for an airport lighting system, a so-called LAM module can be operated in a simplified manner using the secondary voltage converter.

In Figure 2, the transformer 1, 2, 10 according to Figure 1 is connected on the primary side via a regulator 90 with a downstream choke 95 from the mains, on the secondary side a series circuit is operated with a large number of lighting elements 30, 30' etc., each of which has its own lamp transformer 25, 20', etc. A current transformer 40 is used to record the actual value.

A lamp failure signaling unit 55 (LAM module) is assigned to the series circuit, which is controlled by signals from a primary voltage converter 45 and an idle lamp transformer 25a. Previously, a separate voltage converter was necessary in the series circuit. Now the auxiliary winding 15 of the series circuit transformer serves as a secondary voltage converter.

Claims (6)

93 G 3 7Ö5QE Protection claims 1. Series circuit transformer, in particular for use in an airfield lighting system, with a primary winding and at least one secondary winding, preferably several similar windings as taps for the series circuit voltage , characterized in that in addition to the secondary winding (11, 12, 13) an auxiliary winding (15) is also provided as a secondary voltage converter. 2. Series circuit transformer according to claim 1, characterized in that the further auxiliary winding (15) has suitable insulation (16) and is constructed potential-free from the other windings. 3. Series circuit transformer according to claim 1, characterized in that the secondary voltage transformer (15, 16) is designed like a measuring transformer, the voltage of which remains stable regardless of the load. 4. Series circuit transformer according to claim 3, characterized in that the secondary voltage converter (15, 16) is standardized according to the winding ratio of the windings for the series circuit voltage. 5. Series circuit transformer according to claim 3, characterized in that units for signal processing and/or signal display are connected downstream of the secondary voltage converter (15, 16). 6. Series circuit transformer according to claim 5, characterized in that an A/D converter (20) for further digital processing is connected downstream of the secondary voltage converter (15, 16).