DD233251A1 - METHOD FOR OPERATING ELECTRICAL ENGINEERING PLANTS WITH A CENTRALIZED CURRENT LIMITING AND SHORT CIRCUITING DEVICE - Google Patents

Abstract

The invention can be used in the operation of electrical energy systems, with a substantial degree of protection of the expenses should be ensured by the central protection. This is achieved by the fact that via the fault current detection and via the arc fault detection of the electric power switchgear by means of electronic relays and transmission channels (A / D converter and fiber optic cable) a control to adjust the respective Abgaenge to the thresholds for triggering the Zugehoerigen in the central feed limiter Kurzschliessers (13) is carried out with electrodynamic drive and thereby pre-programmed Abscheengigkeiten for switching off the fault currents by means provided for this switch disconnectors q-rated rated current (generally q3) as Abschaltstrom and automatic hooking up a network node with multiple feed with also switching power reduced switching devices and subsequent interconnection act as soon as the fault is switched off, and that at start-up and start-up currents at the same time informed the limiter Kurzschliesser (13) a suppression of the limit and the Limiter Kurzschliesser (13) is subsequently realized, so that a suppression of the limiting effect is achieved. Fig. 2

Description

Field of application of the invention

The invention relates to a method for Betneb of electrical energy systems with a central current limiting and Kurzschließereinnchtung, which is turned on in one and / or multiple feeds

Characteristic of the known technical solutions

To reduce the ever-increasing short-circuit current, the following solutions are known

- Switching reactances, realized by choke and transformers with increased short-circuit voltage, the disadvantage of steady and fluctuating voltage drop

- Reactors and transformers with increased reactance in the event of a short-circuit, disadvantage use of large-diameter winding materials, in some cases no sufficiently fast reaction time

- Use of thyristors, blocking in the event of a fault, disadvantage losses in nominal operation, not readily available in the voltage range from 1OkV

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- use of permanent fuses; Disadvantage: As a central feed-in protection for low-power outlets, they can not be easily adapted or they do not mean protection for them.

The disadvantage that the limiting element is assigned to the feed point at a central location and thus the individual outlet behind the feed point, seen in the direction of energy flow, the current limiting device no longer brings to respond, also adheres to the solutions listed above.

In order to use switching devices with low breaking capacity, it has been proposed to use a central circuit breaker with downstream disconnectors. Disadvantage: occurrence of dead breaks, even with operational switching operations.

Object of the invention

The aim of the invention is to provide a method for the use of a current limiting and short-circuiting device (limiter + short-circuiter) in central feeds of electrical energy systems to safely protect the system and all outlets and to be able to use switching devices with low turn-off.

Explanation of the essence of the invention The technical task

The invention has for its object to provide a method for the control of all possible faults and networks with one (or more) provided limiters + short-circuiters in central feeds of electric power plants, with the low-power outlets safely protected and small fault currents can be safely switched off, said Switch-disconnector and / or low-power circuit breaker should be used.

Features of the invention

According to the invention, this object is achieved in that on the fault current detection of each departure and the arc detection of an electric power switchgear by means of electronic relays and transmission channels (A / D converter and fiber optic cable) a control for adjusting the respective outlets to the necessary thresholds for the triggering the associated in the central feed limiter + Kurzschließers is made with electrodynamic drive and thereby preprogrammed dependencies for switching off the fault currents by means provided switch disconnectors with q-fold, in general q = 3, rated current as Abschaltstrom and automatic connection of a network node with multiple feed also switching power reduced switching devices and subsequent interconnection act as soon as the error is switched off, and that at start-up and start-up currents simultaneously the limiter + Kurzschlie is communicated ereine suppression of the boundary and then implemented by the limiter + short-circuiter so that a suppression of the limiting action is achieved. Advantageously, the limiter + short-circuiter with electro-dynamic drive in its ground connection (short-circuit contact earth) has a switching device, eg. As a vacuum contactor, which is controlled immediately when the switching device is brought to open by the information arc during the movement of the electrodynamic drive and thus immediately abolishes the busbar short circuit, so that the limiter + short circuiter automatically comes in the starting days (operating state), as soon as previously the fault was switched off or the limited short-circuit current by means of a disconnect load breaker, z. B. switch-disconnector or circuit breaker for about three times the rated current was turned off.

It can also be provided that at an arc in the system, the switching device preselected opens after a time and again closes the switching device at a renewed arc fault and shuts off at busbar fault arcs of the Einspeiselasttrennschalter before the limiter + short circuiter and errors in the outflows of the breaker load disconnectors switches off and then the switching device, the earth connection picks up again. In an advantageous embodiment of the invention, it is provided that are triggered at low-power arcs by a fast arc detection at the same time: the activation of the lowest threshold for the limiter + short circuiter and the drive or the ignition of a super fast short circuiter, the only for a low current carrying time of about 10 ms is measured. It is further provided within the scope of the invention that the limiter + short-circuiter is made insensitive at start-up or start-up currents simultaneously with the switching commands by the automatic adjustment for the sensitivity adjustment, d. H. Threshold reduction, off. The inventive method is further characterized by the fact that the limiter + short-circuiting switch on and start-up currents due to the appropriate criterion harmonic content and phase shift voltage / current, coupled with an overcurrent factor, the automatic adjustment for the sensitivity setting of the limiter + Kurzschiießers off, so that even at When the limiter + short-circuiter responds, the movement of its contact rod is interrupted and it returns to the rest position.

According to the method of the present invention, when two or more infeeds are applied, a breaker switch for the busbar sections is equipped with all switches of the electric power plant for the q-fold rated current at general output q = 3) and the short circuit in the order of coupler shifters (designed for q.I _n the most powerful infeed) and then the outgoing switch of the faulty outgoer is turned off, but only by the direct coupling of the information outgoing short-circuit current Ікд Ш q output nominal current l _nA finally receives its trigger signal.

Furthermore, in the case of two and multiple feeders with limiter + short-circuiter in the event of a short circuit fault in any outgoing feeder, the outgoing switch can switch off immediately if the limited outgoing short-circuit current І _Ь д = q · I "a, because all short-circuiters of all limiters + short-circuiters make the short circuit and due to the current commutation, the limited outgoing short circuit current І _Ь д = q · і _п а, while all limited short circuit currents through the short circuiters are canceled by the switching devices in their ground connections.

Finally, with dual and multiple feed-in with limiter + short-circuiter in the event of a short circuit fault in any outgoer, the associated outgoer switch can switch off immediately if the limited outgoing short circuit current IbA = q · IpA, because the limiter + short circuiter of the associated busbar section works as limiter and short circuiter and all other limiter + short circuiter only work as limiter.

The method for operation with a central current-limiting device according to the invention offers the advantage of reliably protecting even low-power outlets or reliably shutting off small fault currents.

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The method according to the invention for operation with a central current-limiting device also eliminates the disadvantages of known protective measures by using switch-disconnectors or power-limited circuit breakers which are designed for the q-times (generally q = 3) value of the feed rated current or the rated outgoing current, and thus also Can switch operating currents.

embodiment

The invention will be explained in more detail below using an exemplary embodiment. The accompanying drawings show in Fig. 1: the structure of a limiter / short-circuiter

Fig. 2: Arrangement of the limiter / short-circuiter in an electric power plant with two feeds. Fig. 1 shows the structure of a limiter 1 / short-circuiter 2, which is arranged after the feed switch 3, designed as a circuit breaker or circuit breaker, designed for the q-fold feed current (generally q = 3), and in front of the busbar 4 of an electric power plant , The limiter 1 / short-circuiter 2 comprises a limiting impedance 5 which can be switched into the current path in the event of a fault, a commutation contact 6, a contact rod 7, a fixed coil 8 and a movable short-circuit cylinder 9, which has a contact system 10 consisting of a commutation contact 6, a contact rod 7 and a ground contact 11, the current path separates, the limiting impedance 5 switches on and the busbar 4 grounded via a ground contact 11 when the switching device 12 is closed. In normal operation, the operating current flows through the feed switch 3 through the stationary coil 8, the commutation 6 and the contact rod 7 to the busbar 4. The principle of the limiter 1 / short circuiter 2 is based on that in case of failure fed by the fault current electrodynamic drive system consisting of the stationary coil 8 and the movable short cylinder 9, the limiting impedance 5 in the current path turns on in the way that the rigidly connected to the shorting cylinder 9 contact rod 7 opens the commutation 6 and the current now via the feed switch 3, the fixed coil 8, the Limiting impedance 5 flows to the busbar 4. After the separation of the commutation contact 6 (no longer connected to contact rod 7), the movement of the short-circuiting cylinder 9 continues until, after a switching path, the contact rod 7 comes into contact with the earth contact 11 and, when the switching device 12 is closed, grounds the busbar 4. If the ground contact 11 is present and the switching device 12 is closed, the limiter 1 / short-circuiter 2 functions as limiter 1 and short-circuiter 2, but if the ground contact 11 is absent or the switching device 12 is opened, then the limiter 1 / short-circuiter 2 functions only as a limiter 1.

FIG. 2 shows the arrangement of the limiter 1 / short-circuiter 2 according to FIG. 1 as limiter + short-circuiter 13 in an electrical energy plant 14 with the inlets 15 and 16, which can be made by cable. The coupling switch 17, designed for the q-times rated current (generally q = 3) of the most powerful feed, has the function of the infeeds 15 and 16 with the associated busbar sections 18 and 19, and the outlets 20, 21 and 22, 23, to couple or decouple

 Single-sided infeed: (coupling switch 17 open)

The limiter + short-circuiter 13 automatically triggers when the ratio of residual current to the rated current of the supply 15i / l _n ^ ρ is (in general, ρ is about 1.9 ... 2.2, threshold for the response of the movement of the short-circuiting cylinder 9) , This occurs whenever shorts occur at or near the bus bar 18 or 19. If the leakage current in the outgoing 20 and / or 21 or 22 and / or 23 is less than the q-fold rated current of the corresponding outgoing (in general q = 3), the outgoer load disconnector 24 and / or 25 or 26 and / or 27 directly controlled by the current detection as part of the fault current sensor 28 and / or 29 or 30 and / or 31 via an electronic relay 32 and / or 33 or 34 and / or 35 and switches off the fault current, because he for the q-times Rated current of the corresponding outlet (in general, q = 3) is designed. Is the fault current z. B. a departure 20 greater than the q-fold rated current (generally q = 3) of the output switch 24, but is still below the threshold for the response of the movement of the short-circuiting cylinder 9, via the current detection, as part of the fault current sensor 28, a electronic relay 32 and an information line 36 made an adjustment 37 of the limiter + Kurzschließers 13, in such a way that via switchable fixed short-circuit windings, as additional parts of the limiter 1 / short-circuiter 2, the threshold for the response of the movement of the Kurzschkißzylinders 9 is lowered. The disconnect load breaker 24 can now turn off the faulty outlet 20 after the response of the limiter + short circuiter 13, after which the switching device 12 cancels the ground connection and the short-circuiting cylinder 9 automatically returns to its rest position (contact rod 7 at commutation 6).

The adaptation 37 of the limiter + short circuiter 13 has on the one hand to increase the sensitivity of the response of the short-circuiting cylinder 9 in low-power faults to the task and on the other hand, the reduction in sensitivity at switch-on and start-up currents.

If it is necessary to switch off arcing faults very quickly, it is intended to equip the electric power plant 14 in addition to the limiters + short circuiters 13 with superfast short-circuiters 38, which are controlled by a fast Störboperkennungerkennung, Bervndteil the fault current sensor 39 and an electronic relay 40, wherein the Current path of the super-fast short-circuiter 38 is relieved after the reaction time of the limiter + Kji zschließers 13 and the Einspeiselasttrennschalter 41 shuts off the fault current

 Double supply: (coupling switch 17 closed)

The following switching concept for dual infeed is also analogously extended to multiple infeeds. For high power feeds to the busbar sections 18 and 19, a short circuit point is fed from both feeds 15 and 16, each with q times the rated current of the feed when the limiter ± short-circuiter 13 operates as the limiter. Since the affected outgoing switch is not intended to switch the 2 q-fold rated current (eg q = 3 2q = 6), but only the q-fold rated current, the coupling switch 17 must decouple the infeeds before switching off the faulty outgoer. If the limiter + short-circuiter 13 operates as a limiter and short-circuiter, another switching regime is implemented in which the supply 15 and 16 of the supply to the fault point are immediately blocked (low-resistance shunt) via the closed short-circuit paths (contact rod 7 to ground contact 11 and switching device 12 closed) and so that the switch of the faulty outgoing can open and the short circuits are canceled because the switching device 12 is open. The coupling switch 17 can be opened at the time of operation of the limiter + short circuiter 13 as a limiter and short-circuiter at the same time with the switch-disconnector of the faulty outlet and thus a busbar section are supplied again.

Claims (1)

-1- 718 77 invention claim Method for operating electrical energy systems with a central current limiting and short-circuiting device, characterized in that via the fault current detection and the Storchchtbogenerkennung the electric power switchgear by means of electronic relays and Ubertragungskanale (A / D converter and fiber optic cable) a control for adjusting the respective output the thresholds for the draw of the associated in the central feed limiter + Kurzschließers (13) is carried out with electrodynamic drive and thereby preprogrammed dependencies for switching off the fault currents by means provided switch disconnectors with q-fold rated current (generally q = 3) as a cut-off and automatic connection of a network node with multiple feed with switching-circuit-impaired switching devices and subsequent interconnection act as soon as the error is switched off, and that at power-up and start-up at the same time the limiter + short circuiter (13) informed a suppression of the limit and informed by the limiter + short circuiter (13) suppression of the limit and then implemented by the limiter + short circuiter (13), so that a suppression of the limiting effect is achieved Method according to item 1, characterized in that the limiter + short-circuiter (13) in its earth connection (11) has a switching device (12), ein B a vacuum protection, which is controlled immediately, if by the information Storag arc during the movement of the electrodynamic drive the switching device (12) is brought to the opening and thus immediately abolishes a busbar short circuit, so that the limiter + short circuiter (13) automatically in the starting position (operating state) comes as soon as the fault has been switched off or the limited short circuit current by means of a disconnection circuit breaker (24 bis 27), Last B. switch-disconnector or circuit breaker for about three times the rated current, has been switched off Method according to item 1 and 2, characterized in that the switching device (12) preselected after a time opens at a arc fault in the system and the switching device (12) closes again at a renewed Storlichtbogen and at the busbar arc of the Einspeiselasttrennschalter (41) before Limiter + short circuit (13) switches off and off in case of errors in the departures (20 to 23) of the output load disconnectors (24 to 27) and then the switching device (12), the earth connection picks up again Method according to item 1, characterized in that, in the case of low - current arc faults, fast arc detection simultaneously triggers the activation of the lower threshold value for the relevant limiter + short circuiter (13) and the drive or ignition of a superfast short circuiter (38) which is only for a low current carrying time of about 10ms is measured Method according to item 1, characterized in that the limiter + short-circuiter (13) is rendered insensitive to the switching commands simultaneously with the starting or starting currents, by adjusting the adaptive adjustment (37) for the sensitivity adjustment, i. h Threshold reduction, switched off, method according to item 1, characterized in that the limiter + short-circuiter (13) at start-up and start-up current due to the appropriate criterion harmonic content and phase shift voltage / current, coupled with an overcurrent factor, the automatic adjustment (37) for the sensitivity setting of the limiter + short circuiter turns off, so that even when the limiter + Kurzschließers (13), the movement of the contact rod (7) is interrupted and he goes back to the rest position. Method according to item 1, characterized in that with two and multiple feed via a coupling switch (17) for the busbar sections all switches of the electric power plant for the q-times nominal current (generally q = 3) of their departure are equipped and the short circuit in the order dome switch (17), (designed for q I _n the leistungsstarksten feed) and then the outgoing switch (24 to 27) of the faulty disposal of but only by the direct coupling of the information leaving short-circuit current Ika S q leaving rated current l _nA be triggering signal is turned off, final sustaining. Procedure according to point ^ characterized in that in two and multiple feed with limiter + short circuiter (13) in case of a short circuit _{fault in any outgoing feeder} switch can switch off immediately if the limited _outgoing short circuit current l _bA Ш ql _nA , because all short-circuiters of all Limiters + short _circuiters (13) establish the short circuit and due to the current commutation of the limited _output short circuit current l _bA S q | _nA , while all limited short-circuit currents on the limiter + short circuit (13) by the switching devices (12) are removed in their ground connections Method according to item 1, characterized in that in the case of double and multiple feed with limiter + short-circuiter (13) in the event of a short-circuit fault in any outgoing feeder the associated outgoing switch (24 to 27) can switch off immediately if the limited outgoing short-circuit current Іь _А = q I "a ¹ St, because the limiter + short circuiter (13) of the associated busbar grating works as limiter and short circuiter and all other limiters + short circuiters (13) only work as limiters 2 pages ⁷ e .hnungen