EP1776747A1

EP1776747A1 - Electric energy transmitting device with a phase conductor and an external conductor

Info

Publication number: EP1776747A1
Application number: EP05767961A
Authority: EP
Inventors: Günther SCHÖFFNER
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 2004-08-13
Filing date: 2005-07-29
Publication date: 2007-04-25
Also published as: CN101006628A; DE102004040246A1; CN101006628B; WO2006018371A1; US20070252443A1; US7514822B2

Abstract

A gas-insulated electrical line comprises at least one phase conductor (1a, 1b, 1b) and one external conductor (2a, 2b, 2c). The phase conductor (1a, 1b, 1c) is surrounded by an external conductor (2a, 2b, 2c). The external conductor (2a, 2b, 2c) can be divided into different sections by means of a switch (3a, 3b, 3c). A division into the different sections ensues when a short-circuit current occurs.

Description

description

Electric power transmission device with a phase conductor and a sheath conductor

The invention relates to a Elektroenergieübertra ^¬ restriction device ter with a phase conductor and an encasing, wherein the phase conductors of the transmission is a elektri¬'s energy flow.

Such an electric power transmission device is spielsweise known from the patent US 5,530,200. The local electric power transmission device is designed as a gas-insulated electrical line. Each of the phase conductors is surrounded by a tubular sheath conductor in each case. The inside of the sheath conductors is filled with an insulating gas under elevated pressure. Gas-insulated lines have a very high current carrying capacity due to their construction. Since the sheath conductors must be pressure-gas-tight and tight, they are made thick-walled. This makes it possible to guide large backflows through the sheathed conductor. Due to the comparatively low impedance of a gas-insulated line and the high current carrying capacity, large short-circuit currents can occur in meshed networks. Switching devices such. B. high voltage

Circuit breakers can no longer control these in part. In the typical application of gas-insulated lines for the transmission of larger amounts of electrical energy into existing network arrangements, there is therefore the danger of overloading of switching devices.

The invention has the object to provide a power transmission device such Elektroener ^¬ configure that in simple way, the rise of a short-circuit current is limited.

The object is at a Elektroenergieübertragungseinrich- of the type mentioned processing according to the invention thereby solves ge ^¬ that the external conductor is separable by means of a switching device.

SHORT- is inserted in a sheath conductors, as usual in gas-insulated lines, occurs due to transitions Induktionsvor ^¬ a return current. The return current is directed in magnitude and phase so that the magnetic fields which emanate from the phase current flowing in the phase conductor and from the return current flowing in the sheath conductor approximately neutralize themselves. By providing a switching device, the flow of the return current in the sheath conductor is interrupted in certain sections. As a result of the asymmetrical conditions thus created, the magnetic fields of the phase current and the return current can no longer be neutralized. Now also occurs outside the sheathed conductor, a magnetic field. This results in an increased inductance of the Gesamtanord ^¬ tion. Because short-circuit currents are to be limited, it is advantageous ^¬ way, to carry out the switching device, for example, as a power switch or power ^¬ electronic components, such as thyristors. In the case of an increased phase current in the phase conductor, the sheathed conductor allows the sheathed conductor to be interrupted rapidly, thereby increasing the inductance of the electrical power transmission device. Due to the increased Induktivitätsbelages a short-circuit current is limited.

A further advantageous embodiment can provide that between an input and an output of the electrical energy Transmission device of the sheath conductor is separable into a larger An¬ number of sections than the phase conductor.

By a plurality of sections, a fine gradation of the influence of a short-circuit current can be provided. Depending on the characteristics of the short-circuit current, such as amplitude or speed of its rise, a more or less strong limitation can be achieved. Thus, the risk of overcompensation in a separation is reduced to large sections of the sheathed conductor.

Furthermore, it can be advantageously provided that the Man¬ telleiter during an operation of the Elektroenergieübertra ^¬ generating device is separable.

An operational separation of the sheathed conductor provides leis ^¬ tet it roenergieübertragungseinrichtung even during a power transmission over the Elekt¬ to rea¬ lust on network operations quickly. Targeted individual sections of the sheathed conductor can be switched on or off.

It may be advantageous that the sheath conductor is separable by means of a repeatedly switchable switching device.

Repeated switchable switching devices, such as switch-disconnectors, load switches or circuit breakers, can also be controlled by higher-level protection and monitoring devices. In this case, the individual switching devices can be matched with one another in terms of their switching behavior, so that, for example, a cascade-like connection or ^{disconnection of} individual shroud conductor sections takes place. A further advantageous embodiment may provide that at least one, in particular each of the sections of the man ^¬ telleiters is electrically grounded.

About at least one low-impedance grounding of the sheathed conductor, it is possible to flow in the jacket flowing back currents to earth from ^¬ . In particular, in the separation of Man¬ telleiters in several sections so return currents can forcibly ^¬ flow over certain grounding points.

Furthermore, it can advantageously be provided that a plurality of Pha¬ senleiter and a plurality of external conductor parallel to each other ver¬ run, wherein at least one is the magnetic field of the power transmission device Elektroener ^¬ influencing ferromagnetic body between the individual conductors arranged jacket.

Due to the ferromagnetic body, the magnetic flux which also occurs outside of the sheath conductor during a separation of the sheath conductors is bundled. Due to the bundling, the inductive effect is additionally reinforced. In ei ^¬ ner reinforcement of the inductance of the Elektroenergieübertra ^¬ supply device in the event of a short circuit circuit current greater impact on the short ^¬, that is, the short-circuit current ^¬ is also influenced by amplitude and phase angle. In order to ensure as uniform as possible act on all Pha ^¬ senleiter and any external conductor, it is advantageous to arrange the ferromagnetic body in each case between adjacent casing conductors. With an arrangement of three phase conductors and three sheath conductors in one plane, two ferromagnetic bodies, for example, can be arranged in each case between the outer phase conductors / sheathed conductors and the inner phase conductor / sheathed conductor. In a so-called triangular arrangement of three phase Conductor and three sheath conductors, it is advantageous to arrange the ferromagnetic body in the interstice area of the electric power transmission device. As a result, a short-circuit current in all phase conductors / sheath conductors is uniformly limited.

Advantageously, it can further be provided that a plurality of phase conductors and a plurality of sheath conductors run parallel to one another and sections of different sheath conductors can be electrically outcrossed.

By a crosswise connecting individual sections of several parallel sheath conductors, a reduction of the sheath currents can be achieved. Such a crossing out is also called "cross bonding." The cyclic exchange of the electrical connections of individual sections of a plurality of conductor leads reduces the return currents in the conductor conductors, since the magnetic fields can no longer be compensated on the basis of phase currents and reduced return currents Due to the reduced reverse current in the sheath conductor, the inductance of the electric power transmission device is increased.

By changing the Induktivitätsbelages not only ei ^¬ ne limit occurring short-circuit currents is possible. Furthermore, by changing the impedance of an electrical energy transmission device, the direction of an energy flow within a network can be influenced. Thus, targeted overloading of individual transmission lines can be prevented by passing the energy flow through alternative paths by means of an impedance change. Advantageously, it can further be provided that at least one ferromagnetic body influencing the magnetic field of the electric power transmission device is arranged between the individual sheathed conductors.

Advantageously, a sheathed conductor may be further provided that a certain sections surrounding the phase conductors, in particular ^¬ sondere is arranged coaxially with respect to the phase conductor.

By enclosing the phase conductor with the sheath conductor, the phase conductor is protected against external mechanical influences. In particular, in the case of a coaxial arrangement of manure conductor and phase conductor, a uniform induction of a reverse current in the sheath conductor can be produced.

A further advantageous embodiment can provide that the sheath conductor is at least partially formed from a pressure-resistant tube.

In one embodiment of the sheathed conductor as pressure-resistant

Pipe, this tube can also be used as encapsulating a gas ^¬ insulated line use. The pressure-resistant tube can then be used both for mechanical stabilization of the electrical energy transmission device, as well as for the gas-tight sheathing of the phase conductor.

In the following, the invention is shown schematically with reference to a Ausführungsbei ^¬ game on a drawing and described in more detail below.

It shows the Figure 1 shows a gas-insulated line with switchable Man¬ telleiter with switched-over conductor, the

FIG. 2 shows the gas-insulated line with broken conductor, the

3 shows a gas-insulated cable with a binding crosswise ^¬ cash shell conductor sections

Figure 4 shows a laying of several phase conductors and a plurality of sheath conductors in a plane and the

FIG. 5 shows a laying of several phase conductors and a plurality of sheath conductors in a triangular arrangement.

In the figures shown equivalent components are provided with the same reference numerals.

In the figure 1, a gas-insulated electrical line is shown schematically in section. The gas-insulated electrical ^¬ cal line has a first phase conductor Ia. The first phase conductor Ia is surrounded by a first sheath conductor 2a. The sheath conductor 2a is divisible via a first switch 3a into a first section 2a 'and a second section 2a''. Parallel to the first phase conductor Ia and the first sheath conductor 2a, a second phase conductor Ib and a third phase conductor Ic and a second sheath conductor 2b and a third sheath conductor 2c are arranged. The three Pha ^¬ senleiter Ia, Ib, Ic and the three external conductor 2a, 2b, 2c are of identical construction, so that the second Man ^¬ telleiter 2b and the third external conductor 2c by means of a second switch 3b and a third switch 3c each in a first section 2b ', 2c' and a second section 2b '' and 2c '' are divisible. The three phase conductors Ia, Ib, Ic, and the three sheath conductors 2a, 2b, 2c serve to transmit an electrical energy flow within a three-phase AC voltage system. On the input side of the gas-insulated electrical line acting as an electric power transmission device, a feeding electric power supply network 4 is arranged. The electrical energy supply network 4 has, for example, a plurality of generators or also feed-in points from adjacent electric energy supply networks. Within the Elektroenergieversorgungsnet ^¬ zes 4 grounding points are for example provided in the individual phases of the three-phase alternating voltage systems ^¬ at substations. At the output of the gas-insulated electrical conductor, an electrical pickup 5 is arranged. The buyer 5 is for example an industrial plant with a

Variety of electric motors, resistance heaters, etc. With a large power requirement of the pickup 5 large amounts of energy from the electric power grid 4 can be transmitted via the gas-insulated line to the consumer 5. A gas-insulated line is constructed of a phase conductor Ia, Ib, Ic, which is surrounded by a sheath conductor 2a, 2b, 2c. The sheath conductor 2a, 2b, 2c is formed in the form of a thick-walled tube, which consists of electrically lei ^¬ tendem material. The sheath conductor 2a, 2b, 2c is arranged in a gastight manner around the phase conductor 1a, 1b, 1c. The

Filled inner conductor of the shell 2a, 2b, 2c at a gasisolier ^¬ th electric wire with a ste¬ under elevated pressure Henden insulating gas. In order to comply with the permissible contact stresses, the sheath conductors 2a, 2b, 2c are each connected to a ground potential. This makes it possible to lay the gas-insulated electrical lines directly in the ground, or it may be on the provision of a contact Protective device for the jacket conductor 2a, 2b, 2c are dispensed with.

In the figures, of the sheathed conductor is schematically shown an interruption point, wherein the interrup ^¬ monitoring point by means of switches 3a, 3b, 3c can be bridged. In order to ensure compressed gas insulation of the phase conductors Ia, Ib, Ic in this area as well, it is possible, for example, to use sections of electrically insulating material as compressed gas encapsulation there. These electrically insulating sections can then be bridged by means of a switchable electrically conductive connection.

In a regular operation on the part of the pickup 5, the switches 3a, 3b, 3c are closed, so that the sheath conductors 2a, 2b, 2c are continuously electrically conductive. In the individual phase conductors Ia, Ib, Ic, the phase current flows to the acceptor 5. Due to electromagnetic induction, a so-called reverse current is induced in the shell conductors 2a, 2b, 2c. The return current has approximately the same amplitude as the phase current in the phase conductors Ia, Ib, Ic. However, a phase angle offset by 180 ° is recorded. The egg ^¬ ing induction of the electric power transmission device is almost exclusively determined by the arrangement of the sheath conductors 2a, 2b, 2c and the phase conductors Ia, Ib, Ic. The magnetic field is very low outside the sheath conductors 2a, 2b, 2c. When a short circuit occurs on the pickup side 5, the short circuit is supplied from the electrical power supply network 4 via the gas-insulated line. In the case of a correspondingly high-power electrical energy supply network 4, there may be a rapid increase in a short-circuit current that is difficult to control. The gas-insulated electrical line is quite in the Able to carry the short-circuit current. The height of the short-circuit current to be controlled is essentially limited by the circuit breakers used, which are provided for switching off such a short-circuit current. When a short-circuit current is detected, an opening of the switches 3a, 3b, 3c and thus an interruption of the Man¬ telleiter 2a, 2b, 2c respectively in a first section 2a ', 2b', 2c 'and a second section 2a'', 2b '', 2c '' (see Figure 2). The triggering of the switch can be effected, for example, by monitoring the reverse current flowing in the sheath conductor 2a, 2b, 2c, or the switches 3a, 3b, 3c can be activated by protective devices which monitor the phase current in the phase conductors 1a, 1b, 1c. Furthermore, the earth connection of the conductor conductors 2a, 2b, 2c is separated at the output end of the gas-insulated electrical line. Due to the division into several sections, the flow of a return current over the entire of the sheathed conductor 2a, 2b, 2c is no longer possible. As a result, the overall system is brought into an asymmetrical position and the magnetic field also extends outside of the

Sheath conductors 2a, 2b, 2c. This results in an increased inductance of the arrangement formed from phase conductors and sheath conductors. The increased inductive component increases the overall impedance of the gas-insulated electrical line (between the input side and the output side). The Incr ^¬ te impedance causes circuit current limiting of the current flowing Kurz¬. If the increase in the impedance are terstützt addition un¬, there is still the possibility ferromagnetic body between the encasing conductors 2a, 2b, 2c or outside the external conductor 2a, 2b, 2c to ^¬ order (see FIG. 4 and 5) , The ferromagnetic bodies act to bundle the outside of the sheath conductor 2a, 2b, 2c occurring magnetic field. The ferromagnetic body acts as an iron core.

Since, in the stationary state, the magnetic fields emanating from the current in the phase conductors Ia, Ib, Ic and the return currents in the associated sheath conductors 2a, 2b, 2c compensate each other, with the conductor leads 2a, 2b, 2c switched on no negative influence on the impedance behavior of the gas-insulated electrical line by the ferromagnetic bodies.

In addition to the limitation of a short-circuit current on the separation of the coat can ^¬ conductors 2a, 2b, 2c also used to wer¬ the, tung to the impedance of a Elektroenergieübertragungseinrich- which is located, influences to be ^¬ within a network. By changing the impedance of a single electric power ^transmission device within a network, the load flow in the network can be influenced and selectively controlled.

In the figure 3, the so-called "cross bonding" of Man ^¬ is telleiters shown schematically. Due to the cyclic swapping of individual sections of sheath wires belonging to ei ^¬ nem three-phase system, the current flowing in the jacket conductors back flow is reduced. With a reduction of the

Rückstromes it is no longer possible that of the phase current flowing in the phase conductors outgoing magnetic field by the return current almost completely compensate. In this case, magnetic fi lders are to be detected outside the sheath conductors. The effect of these magnetic fields can be further enhanced by the introduction of ferromagnetic bodies between the sheath conductors. To a Reduzie¬ tion of the return current by the outcrossing of Mantelleiterab- cut to achieve, it is necessary, the gas-insulated conductor on the input side and the output side to it ^¬. More ground points are set aside during the "cross bondings". By appropriately switching means 6a, 6b, it is possible to use a circuit-switched shell conductor ei¬ ner phase in several portions to divide and a cross ^¬ as electrical contacting of individual sections ver ^¬ VARIOUS shell conductor of various phases of a Drehstrom¬ systems perform. In a corresponding coupling then automated unwanted earthing points 7 are separated ^¬ bar.

FIG. 4 shows a laying arrangement of a gas-insulated electrical line, in which the three phase conductors Ia, Ib, Ic belonging to an energy transmission system for three phase alternating current and the three arranged coaxially with the three phase conductors Ia, Ib, Ic Sheath conductors 2a, 2b, 2c lie in one plane. Between the sheath conductors 2a, 2b, 2c, a first ferromagnetic body 8 and a second ferromagnetic body 9 are arranged. The ferromagnetic bodies 8, 9 are used for bundling the magnetic field in the case of the separation or "cross-bonding" of sheathed conductors 2a, 2b, 2c. FIG. 5 shows three phase conductors Ia, Ib, Ic and three In the center region of the triangle, a third ferromagnetic body 10 is arranged, which in the case of an uneven loading of phase conductors Ia, Ib, Ic and associated sheath conductors 2a, 2b, 2c then becomes the thinner The ferromagnetic bodies can be made in different shapes and materials, such as stratified bodies, etc. The arrangement of the ferromagnetic bodies can also be used take place at further in Figs. 4 and 5, not shown Posi¬. Thus, for example, be provided to design support frames particularly massive and use them as a ferromagnetic body. The ferromagnetic bodies can thus also be arranged laterally or above or below the sheath conductors 2a, 2b, 2c.

Claims

claims

1. electric power transmission device with a Phasenlei¬ ter (Ia, Ib, Ic) and a shell conductor (2 a, 2 b, 2 c), wherein the phase conductor (Ia, Ib, Ic) is used to transmit a elektri¬'s energy flow, characterized in that the sheath conductor (2a, 2b, 2c) by means of a switching device (3a, 3b, 3c) can be separated.

2. The electric power transmission device according to claim 1, characterized in that between an input and an output of the electrical energy transmission device, the sheath conductor (2a, 2b, 2c) can be separated into a larger number of sections than the phase conductor (1a, 1b, 1c).

3. electric power transmission device according to one of claims 1 or 2, d a d u c c h e c e n e c e in that the sheath conductor (2 a, 2 b, 2 c) during an operation of the electric power transmission device can be separated.

4. The electric power transmission device according to claim 1, wherein the sheath conductor is separable by means of a switching device that can be repeatedly switched (3a, 3b, 3c).

5. Electric power transmission device according to one of claims 1 to 4 An¬, characterized in that at least one, in particular each of the sections of the man ^¬ telleiters (2a, 2b, 2c) is electrically grounded.

6. Electric power transmission device according to one of claims 1 to 5, characterized in that a plurality of phase conductors (Ia, Ib, Ic) and a plurality of sheath conductors (2a, 2b, 2c) run parallel to each other, wherein at least one of the magnetic field of the electric power transmission device influencing ferromagnetic body (8 , 9, 10) between the individual conductor conductors (2a, 2b, 2c) is arranged.

7. Electric power transmission device according to one of claims 1 to 5 An¬, characterized in that a plurality of phase conductors (Ia, Ib, Ic) and a plurality of sheath conductors (2a, 2b, 2c) parallel to each other and sections of different sheath conductors (2a, 2b, 2c) electrically are auskreuz¬ bar.

8. The electric power transmission device according to claim 7, characterized in that at least the magnetic field of electric power transmission ^¬ means influencing ferromagnetic body (8, 9, 10) between the individual cladding conductors (2a, 2b, 2c) ange¬ allocates is.

9. The electric power transmission device according to one of An¬ claims 1 to 8, characterized in that a portion surrounding a sheathed conductor (2a, 2b, 2c) the Phasenlei ^¬ ter (Ia, Ib, Ic), in particular coaxially, to the phase ^¬ conductor (Ia Ib, Ic) is arranged.

10. The electric power transmission device according to one of claims 1 to 9, wherein a sheath is formed at least partially from a pressure-resistant tube.