DE29622654U1 - Electrical system for the medium voltage range - Google Patents

Description

Drs. Fitzner &

Legal and paternalistic administration Ratingen - Berlin

Utility model application

Rating:

Dr. iur. Ulrich Fitzner

Lawyer

Dr.-Ing. Dr. iur. Uwe Fitzner

Lawyer and Patent Attorney / European Trademark Attorney

Dipl.-Chem. Dr, Ruth Christophersen

Patent Attorney / European Patent Attorney / European Trademark Attorney

Berlin:

Dipl.-Chem. Dr. Bernhard Jungblut

Patent Attorney / European Patent Attorney / European Trademark Attorney

Attorney file: RIT/G/971

Date: 27.01.1997

Applicant: Ritter Starkstromtechnik GmbH & Co.
Luisenglück 20
44225 Dortmund (Barop)

Title:

Electrical system for medium voltage range

Priority:

Branch: from 196 38 746.9-34 (Ans: 11.09.1996)

Ratingen office: Kaiserswerther Straße 74 - 40878 Ratingen Tel.: 02102/42370 Fax: 02102/46851

Berlin office: Habersaathstr. 58-10115 Berlin

Tel.: 030/283052-0, Fax: 030/283052-25

Berliner Bank AG, Berlin, (bank code 100 200 00) account 405 749 030

Drs. Fitzner & Christophersen, Ratingen - Berlin

Electrical system for medium voltage range

Description

The invention relates to an electrical system for the medium voltage range in a closed design, in particular a switchgear, with at least one encapsulated electrical function module and with a pressure relief channel running in the transverse direction of the functional module, whereby the functional module has a plurality of functional spaces for medium voltage functional elements that are closed off from one another, and whereby the functional spaces are connected to the pressure relief channel via emergency pressure relief elements. - Electrical systems in the sense of the invention serve in the broadest sense for electrical energy distribution, thus including not only switchgear but also transformer stations, for example. The medium voltage range is defined as an operating voltage of more than IkV to approx. 4OkV, whereby the upper limit can also be higher. Air is usually used as an insulating medium. An electrical system in a closed design has no significant openings between the interior of the system and the surroundings of the system during normal operation and is gas-tight in the sense that pressure surges occurring inside the system only penetrate slightly into the immediate surroundings of the system. Functional modules with medium-voltage electrical functional elements that are practically pressure-tightly closed off from other modules in the system are referred to as encapsulated. Functional spaces that are closed off from one another are separated by pressure-tight partition walls.

Drs. Fitzner & Christophersen, Ratingen - Berlin

separated from each other. It goes without saying that suitable pressure-resistant bushings, e.g. for electrical cables, are provided. If contacts are arranged in the partition walls, these are also pressure-resistant. Pressure-resistant always means a structure that can withstand pressure surges occurring in a system (possibly also due to a fault) to such an extent that they are not uncontrolledly relieved. Electrical functional elements can be, for example, busbars, circuit breakers, transformers, cable connection elements, etc. The functional modules are usually electrically connected to one another via the busbars.

In electrical systems for the medium voltage range, malfunctions in the form of arc faults cannot be ruled out. The amounts of energy (thermal or sound) and/or gas that occur in an electrical function module during an arc fault and the associated pressure surges can reach very considerable levels and cannot be fully absorbed by the encapsulation of a function module without further ado. For this reason, in practically all electrical systems for the medium voltage range, a pressure relief channel is installed to dissipate the energy and, if applicable, the fault gases. The pressure relief channel extends over all electrical function modules. The functional spaces for medium voltage functional elements are connected directly or indirectly (if applicable via discharge channels) to the pressure relief channel via fault pressure relief elements. In this respect, in the event of an arc fault, the encapsulation for the affected function module or the affected function space is deliberately broken through by opening the fault pressure relief elements; the encapsulation of unaffected function modules or

Drs. Fitzner & Christophersen, Ratingen - Berlin

However, functional spaces remain. The pressure relief channel usually opens into the open air (if the outlet is arranged in such a way that it does not pose a risk to people) or into a device for absorbing the energy and/or the sometimes toxic accident gases. The overall arrangement ensures that a person in the vicinity of the system cannot be injured in the event of an arc fault due to the thermal energy, pressure surge or accident gases that occur.

A system of the design mentioned at the beginning is known, for example, from the literature reference DE 39 27 835 A1, Fig. 1. As part of these measures, the electrical function module is equipped on its top with emergency pressure relief elements for the medium-voltage functional spaces. The pressure relief channel is installed above the electrical function module and adjacent to the emergency pressure relief elements. This structure can be improved for various reasons. Firstly, it is complex to manufacture to first set up one or more electrical function modules and then to attach the pressure relief channel designed as a structural unit. Secondly, it is a disadvantage that a special pressure relief channel has to be built for each electrical system in accordance with the number of electrical function modules provided and in accordance with the specified spatial conditions at the installation location of the system. In this respect, the concept of the modular structure with regard to pressure relief is disrupted in a disruptive way in these known systems.

In contrast, the invention is based on the technical problem of developing an electrical system for medium-voltage

Drs. Fitzner & Christophersen, Ratingen - Berlin

area that can be constructed without additional measures simply by joining together electrical function modules, in such a way that the pressure relief channel is also included in the basic modular concept.

To solve this technical problem, the invention teaches that the electrical functional module is hermetically sealed as an independent unit, that all functional spaces for medium-voltage functional elements are designed directly adjacent to the one pressure relief channel arranged inside the functional module, and that the pressure relief channel is designed to run in a straight line in the direction of a pressure relief opening in the electrical system. - The term hermetically sealed means that even in the event of an arc fault, no openings can occur in the encapsulation of the electrical functional module or that no pressure relief occurs via any exposed outer surface of the functional module. All pressure relief takes place via the fault pressure relief elements inside the functional module into the integrated pressure relief channel. The term "independent unit" is intended to express that the electrical function module not only forms a module in terms of electrical functions, but that the electrical function module is also built and functions as a unit in terms of controlling an arc fault, without additional external attachments to the electrical function module in the course of creating an electrical system from the functional modules. A pressure relief opening is the open end of a pressure relief channel which is arranged on the outside of a terminal electrical function module. Accordingly, a

Drs, Fitzner & Christophersen, Ratingen - Berlin

The electrical system according to the invention can have two pressure relief openings or just one pressure relief opening. In the latter case, one of the ends of the pressure relief channel is provided with a pressure-resistant closure.

Although it is also known in principle from the literature reference DE 39 27 A1, but there Fig. 2, to integrate one of several pressure relief channels into a functional module, in the known system this structure follows from geometric constraints due to the duplex structure (double arrangement of the electrical functional elements) and from the correspondingly high number of required functional spaces, which must be able to be depressurized in the event of a fault. In the event of a fault, however, some of the functional spaces of this known system are always depressurized in the "classic" way outside the functional module and into a separately installed pressure relief channel, which means that the above-mentioned disadvantages also apply here. 20

An electrical system according to the invention can advantageously be set up in a particularly simple manner, since the basic concept of the modular structure has been consistently developed and implemented. To set it up, it is only necessary to select electrical function modules with the desired functions, set them up next to each other at the location in the desired order and connect them to each other. The connection essentially extends to the contacting of busbar connections and the sufficiently pressure-tight joining of the pressure relief channels. The latter can be done, for example, using insert elements designed like sleeves. The individual dimensioning and

Drs. Fitzner & Christophersen, Ratingen - Berlin

Production of a pressure relief channel to be attached. It goes without saying that in an electrical system according to the invention, not only are the busbar connections of various electrical function modules arranged in a way that is compatible with one another, but also that the pressure relief channels of various function modules are essentially aligned with one another and are compatible in terms of connection technology. Overall, this results in a considerable simplification in terms of assembly technology, combined not only with a saving in material with regard to the pressure relief channel, but also with a considerable saving in space. An electrical system according to the invention is less high without the other external dimensions having to be increased in a disruptive manner.
15

The electrical functional module is advantageously designed as follows with regard to the internal arrangement of the functional spaces. The pressure relief channel is arranged in the upper area of the functional module, preferably adjacent to an upper end wall of the functional module. In the upper area of the functional module, a busbar space is arranged at the rear and a low-voltage space is arranged at the front. The pressure relief channel is arranged between the busbar space and the low-voltage space. In the lower area of the functional module, a cable connection space is arranged at the rear and a power element space, for example a circuit breaker space, is arranged at the front. The cable connection space and the power element space are adjacent to one another.
30

In a particularly preferred embodiment, the cable connection space is designed such that it surrounds the power element space laterally, preferably on both sides, and extends to the pressure relief channel.

Drs. Fitzner & Christophersen, Ratingen - Berlin

In particular, it is advisable to install pressure relief flaps as emergency pressure relief elements.

In the simplest and preferred case, the pressure relief channel is designed without any filling. However, it is also possible in principle for the pressure relief channel to contain absorption media to absorb the thermal energy and the sound energy from accident pressure surges and/or accident gases.
10

As part of an electrical system according to the invention, modules with non-electrical functions can also be set up. For example, an encapsulated fault module or several encapsulated fault modules can be set up to absorb the energies and gases generated as a result of an arc fault. With regard to a particularly suitable fault module, reference is expressly made to patent application DE 195 20 689.3-34. It goes without saying that a fault module known in this respect is modified so that its deflection device can be connected directly to a pressure relief opening. If no fault module is to be used, it is expedient to connect an outlet channel to the pressure relief opening, which is laid in a location that is safe from a safety point of view, for example in an external wall of a building at a height of over 2-3 m, in order to relieve pressure waves and fault gas flows to the outside.

In the following, the invention is explained using drawings which merely represent an embodiment. They show

Fig.l: a front view of an electrical system according to the invention,

Drs. Fitzner & Christophersen, Ratingen - Berlin

Fig.2: a section through an electrical functional module along the cross-sectional plane A-A in Fig.l and

Fig.3: a section through the object of Fig. 2 along the cross-sectional plane B-B.

The electrical system 1 shown in Fig. 1 is of a closed design and is designed for the medium voltage range. In the exemplary embodiment, the electrical system 1 consists of a plurality of encapsulated electrical function modules 2, which are arranged next to one another and connected to one another. The dashed lines show a pressure relief channel 3 running in the transverse direction of the function modules, which ends at its right end with a pressure relief opening 4. What cannot be seen is that a pressure-resistant cover plate is attached to the left end of the pressure relief channel, which seals this end pressure-tight even in the event of an arc fault.

In Fig. 2 it can be seen that the electrical function module 2 has a plurality of mutually closed functional spaces 5, 6, 7 for medium-voltage functional elements. In the example, the functional elements are busbars 8 in the busbar space 7, a circuit breaker 9 in the circuit breaker space 6 and cable connection elements 10 in the cable connection space 5. In addition, a low-voltage space 11 is set up in which low-current circuits or low-voltage circuits (not shown for the sake of simplicity) are arranged for control, regulation and measurement purposes. The low-voltage space 11 does not require any measures for pressure relief, since no high voltage occurs in it and therefore no

Drs. Fitzner & Christophersen, Ratingen - Berlin

Arc faults can occur. Finally, the pressure relief channel 3 can be seen, which is connected to the functional spaces 5, 6, 7 via pressure relief flaps 12, 13, 14 (see also Fig. 3). In the cross-sectional drawings Fig. 2 and Fig. 3, the lines drawn with a thick line width represent pressure-resistant walls, with the exception of those places where pressure relief flaps 12, 13, 14 are arranged.

From a comparative examination of Figures 1-3, it can be seen that all electrical function modules 2 are hermetically sealed and designed as independent units. In particular, it can be seen from Figure 1 that the top of the electrical system 1 assembled from the function modules 2 also forms a hermetically sealed surface even in the event of an arc fault. To illustrate this, the abutting edges between the function modules 2 on their top are not shown.

By comparing Figures 2 and 3, it can be seen that all functional spaces 5, 6, 7 for medium-voltage functional elements 8, 9, 10 are designed to be directly adjacent to the single pressure relief channel 3 arranged inside the functional module 2. All functional spaces 5, 6, 7 are pressure-tightly separated both from the outside and from each other; only in the areas of the pressure relief flaps 12, 13, 14 can excess pressure escape directly into the pressure relief channel 3. In Figure 1, it can be seen that the pressure relief channel is designed to run in a straight line in the direction of the pressure relief opening.

The electrical function module 2 shown in Figures 2 and 3 is constructed in detail as follows. The pressure relief channel 3 is in the upper area of the

Drs. Fitzner & Christophersen, Ratingen - Berlin

Function module 2, namely adjacent to an upper end wall 15 of the function module 2. In the upper area of the function module 2, a busbar compartment 7 is arranged at the rear and a low-voltage compartment 11 at the front. The pressure relief channel 3 is arranged between the busbar compartment 7 and the low-voltage compartment 11. In the lower area of the function module 2, a cable connection compartment 5 is arranged at the rear and a power element compartment 6, here a circuit breaker compartment 6, at the front. The cable connection compartment 5 and the power element compartment 6 are adjacent to one another. In detail, the cable connection compartment 5 is designed in such a way that it extends around the power element compartment 6 on both sides up to the pressure relief channel 3 (see in particular Fig. 3).

What is not shown in the example is that in Fig. 1, to the right of the rightmost functional module 2, an emergency module is connected. The deflection device of the emergency module is arranged so that its inlet is aligned with the pressure relief opening 4. The deflection device and the pressure relief opening 4 are connected to one another in a pressure-tight manner. Instead of the emergency module, a pressure relief chimney that leads to the outside can also be connected to the pressure relief opening 4.

Claims (6)

Dres. Fitzner & Christophersen, Ratingen - Berlin Protection claims 1) Electrical installation (1) for the medium voltage range in a closed design, in particular switchgear, 5 with at least one encapsulated electrical function module (2) and with a pressure relief channel (3) running in the transverse direction of the functional module (2), wherein the electrical functional module (2) has a plurality of mutually closed functional spaces (5,6,7) for medium-voltage carrying functional elements (8,9,10) and wherein the functional spaces (5,6,7) are connected to the pressure relief channel via emergency pressure relief elements (12,13,14),
20 characterized, that the electrical functional module (2) is hermetically sealed as an independent unit, that all functional spaces (5,6,7) for medium-voltage functional elements (8,9,10) are designed to be directly adjacent to the one pressure relief channel (3) arranged inside the electrical functional module (2), and that the pressure relief channel (3) is designed to run in a straight line in the direction of a pressure relief opening (4) of the electrical system (1). Drs. Fitzner & Christophersen, Ratingen - Berlin 2) Electrical system according to claim 1, characterized in that the pressure relief channel (3) is arranged in the upper region of the electrical function module (2), preferably adjacent to an upper end wall (15) of the electrical function module (2). 3) Electrical system according to claim 1 or 2, characterized in that in the upper area of the electrical function module (2) a busbar compartment (7) is arranged at the rear and a low-voltage compartment (11) is arranged at the front, and that the pressure relief channel (3) is arranged between the busbar compartment (7) and the low-voltage compartment (11). 4) Electrical system according to one of claims 1 to 3, characterized in that in the lower area of the electrical function module (2) a cable connection space (5) is provided at the rear and a power element space (6), for example a circuit breaker space (β), is provided at the front, and that the cable connection space (5) and the power element space (6) are adjacent to one another. 5) Electrical system according to one of claims 1 to 4, characterized in that the cable connection space (5) extends laterally around the power element space (6), preferably on both sides, up to the pressure relief channel (3). Drs. Fitzner & Christophersen, Ratingen - Berlin 6) Electrical system according to one of claims 1 to 5, characterized in that pressure relief flaps 5 (12, 13, 14) are set up as pressure relief elements in the event of an accident (12, 13, 14).