HUE029395T2

HUE029395T2 - Mûködtetõ áramkör megszakító vezérlésére

Info

Publication number: HUE029395T2
Application number: HUE13717515A
Authority: HU
Inventors: Allmen Peter Von
Original assignee: General Electric Technology Gmbh
Priority date: 2012-04-24
Filing date: 2013-04-22
Publication date: 2017-02-28
Also published as: CN104254899A; KR102068829B1; KR20150010958A; ES2590856T3; US20150103459A1; RU2615779C2; US10410817B2; EP2842151A1; FR2989824A1; FR2989824B1; IN2014MN02075A; EP2842151B1; WO2013160217A1; RU2014146946A; PL2842151T3

Description

7XSÛ35/MK {EP2842ÍS1)

Működtető áramkör megszakító vezérlésére-5 DESCRIPTION

TECHNICAL ÉEID

The present Invention relates ti an actuator device for controlling electrical disconnection equipment,.such es a medium-voltage or a high-voltage circuit breaker.

STATE OF T ME PRIOR ART A Circuit breaker,: e,g; in a gas-insulated substation I6IS) is fitted with a controller, That controller supplies the ghergy and torque necessary for moving the contacts of the Circuit breaker,

Controllers may be of the hydraulic, gas-flow, w spring type. The present invention Is described more particularly for a spring controller, hut also applies to other types of controller.

Under the effect of an actuator mechanism, a spring controller acts mechanically in order to open or dose the contacts of a circuit breaker, A conventional actuator mechanism Includes a coil that drives a plunger when current passes through the coil. The plunger is connected to a ratchet mechanism in such a manner that the coil drives the mechanical operation of the spring controller by moving the plunger and consequently the ratchet mechanism, A coil suitable for having a current passing therethrough that is capable of moving the plunger and the ratchet typically includes II03 turns wound around a magnetic core. That means that the inductance of the coil is high,, as is its time constant since it is proportionáTto inductance, Thus, the acting time with known solutions commonly reaches S.S milliseconds fmsi·

This value contributes sighlfldbbtly to the breaking time of the elrepít breaker. Since high'-voltage circuit breakers in electrical networks at 60 Hertz |H?1 are often required to eliminate a fault in two cyelesÿ their breaking time is limited to 33.3 ms. In order to reach thiswkfg, theacting time of the actoitor mechaoism sliould io limited as much as possible, Docuoient US 5 889 849 relates to a controller mechanism for a gas valve In a furnace* That mechanism includes two colls for actuating the gas valve. The coils are driven by a single Input signal emitted try a microprocessor and amplified by a transistor.

That Impies that a failure of the microprocessor or of the transistor would prevent the control mechanism from operating. Thus., even transposing the teaching of that document for use In controlling electrical disconnection equipment, such as a circuit breaker, would not obtain a controller device that presents a satisfactory level of reliability. indeed, a medlumwoltage or high-voitage eircuif breaker: 1$ in serviceler a duration that typically spans 25 to 40 years. That duration Is very lung for an actuator circuit and in particular for components such as transistors, which may have shorter lifespans, A solution In which a component risks causing a fault in the circuit breaker is not satisfactory.

Document US 5 159 52,2 relates to an electric dutch also including two coifs. One of sali colls actuates the clutch and the other holds it in lis actuated state.

In an embodiment, a first input terminal and a first transistor power a first coif, while a second input terminal and a second transistor power both coils.

Transposing the teaching of that, document for use in controlling :electrical: dlSConne£tion:epMipft544h such as a circuit breaker, does not give rise to any drawback linked to the risk of a transistor failing. However, that solution Is more complex ami requires In particular two separate power supplies,

Uocimpf JP 2009/302358 discloses a circuit in which a coil is powered via a transistor and a capacitor in a first stage, in a second stage, the transistor is switched off and the current flowing in the coil is limited by a resistance element in series with the coil.

That type of circuit cannot be transposed fopuse in controlling a arcúit breaker. For P elrepít breaker, the current that muff be broken In the activation circuit mhst he less than 4 amps {A) (DC), according to iht standard 822271-1, §S,4.4.S,4. That implies that, for a given voltage, some minimum resistance value Is necessary. By way of example, for 110 volts (V) and A A, the sum of the resistances of the coil and of the resistance element must be at least 27,5 ohm.fpf, 1rs addition, the dead time of the mechanism should he short, typically less than 300 ms in order to comply with the operating cycle set out in IEC standard £2272.1011 §4.104.

That implies that the intrinsic resistance of the coil should be Ipv», typically 4 O. Thus., the resistance of the resistance element is at least 23.S Q.

Those haloes heve two consequences; the energy dissipated by the resistance element is six limes greeter than that dissipated by the coil, which Is oot desirable, farther, the coll needs to have a very small number of turns In order to have very low Intrinsic resistance. Ä current of 4 A flowing in said coil would not create sufficient magnetic flux for actuating the movable portions into their actuated positions.

Document US 4 222 123 A concerns a circuit for driving a solenoid at a high speed including a shoke coil and two branches connected to the solenoid. SUMMARY OP THE IHVENTIOÍ

The invention alms to resolve the problems of the prior art by providing an actuator circuit for actuating a circuit breaker controller,, the circuit being characterised In that it comprises two branches in pardlil between two terminals, and in that the first branch includes only a first coll; and the second branch includes a second coil having impedance that Is lower than the fust, in series with a switch controlled by a switch circuit.

By means of the invention,, the action time of the actuator circuit Is reduced and remains compatible with the speed requirements of a circuit breaker.

The first branch has a function of providing redundancy. If the second branch becomes inoperative, e,g, because of the falusé of a component, then the first branch ensures the actuation function of the contrôler. Thus,, failure of a component does not prevent the device from operating. Since the ifst coil has impedance that is greater than the second., the current flowing in the first col remains low relative to the current in the second coil and may be broken by an auxiliary switch.

According to a preferred characteristic,, the switch circuit is adapted to limit the strength of the current flowing in the second coil and to open the second branch after a predetermined time period., after a pofeoiaI difference has been applied between The two terminals.

Thus, the current to be broken remains at a value that is less than 4 A |DC| and compiles with the conditions of I EC standard 622271-1. kmsMUg Ιο a preferred characteristic the switch includes a component selected from a flefd-dffed: transistor., so NRN junction transistor a thyristor, and a mechanical relay.

These components contribute to obtaining a short action time for the actuator circuit.

According to a preferred characteristic, the first and the second coils are wound around a single core. Thus, induced currents are created, in particular ή current in the first coil when the current is broken in the second coil, which makes it possible to ensure the plunger performs a movement that is complete.

The invention also provides a clrdPit Irealer contfoiler including an actuator circuit as : described above, it may be a spring controller.

The invention further provides a circuit breaker Including a controller provided with ait actuator circuit as described above.

The controller and the circuit breaker present advantages analogous to those exposed above. BRIEF DBCJtirfiCTN OF THF: DRAWINGS-

Other characteristics and advantages appear on reading about a preferred embodiment described by way of non-limiting example, and with reference to the figures in which: ' Figure 1 is a diagram showing a circuit breaker fitted with a spring controller provided with an actuator circuit of the Invention; and r Flgure 2 shows the actuator circuit of the invention,

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

With reference to Figure 1, a medium- or high-voltage circuit breaker 20 includes a spring controller 21 that supplies the energy and torque necessary for moving the contacts of the circuit breaker.

The circuit breaker 20 and the controller 21 are conventional except concerning an actuator circuit 22 that drives the controller IX. The circuit breaker and the controller are not described in detail hero. The actuator circuit is described in detail below.

With reference to Figure 2, the actuator circuit of the invention comprises two branches in parallel between two terminals 5 and 6 to which a potential difference may be applied In order to make the actuator circuit operate:

The first brasch includes only wvmàft i. % way of example, the coll 1 comprises 10ÖÖ turns and presents impedance of 35 Û. This branch has a function of providlbg redundancy. If the second branch becomes inoperative, e,g. because of the failure of a component, then the first branch ensures the actuation fonction of the spring controlier. It Is then In a mode of operation known as “degraded operaion mode“.

The second branch comprises a coil 2 and other componlnts that are described below. By way of exemple, the coll 2 comprises 363 turns and presents an impedance if 3.5$ O. Naturally, other impedance values may be selected for the colis X and 2, provided that the impedance of the coll 1 Is greater than that of the coli ÏL The second branch provides the “normal“ mode of operation.

Because of the difference in impedances., the operation In degraded mode first branch) will thus be somewhat slower than in normal mode {second branch). By way of example, values measured on a prototype are 3,2 ms in normal mode and 5,5 ms in degraded mode.

In: ahi embodiments the coils 1 and 2 are both formed by winding around a single core.

The second branch is described below. From the terminal 1* the Coll 2 Is connected in series with a switch that is capable of opening the second branch, The switch is connected to the fermihil 4 In a preferred embodiment, the switch mainly comprises a transistor 3, The transistor 3 is a field-effect transistor, e.g, of the niatat-oxide-semiconductor field-effect transistor (MOSTET) type. The drain of the transistor 3 is connected to the coil 2* and the source of the transistor 3 Is connected to the terminal 6. Other types may be used as a switch, In particular in ÜN Junction transistor, a thyristor, or a mechanical relay.

The transistor 3 makes it possible to limit the strength of the current flowing in the coll 2 to a value that; makes it possible to break the current using an auxiliary switch. As mentioned above, the breaking capacity of an auxiliary switch is limited to a maximum Current of 4 A. With a coll 2 having impedance of 3,55 Q, and in the absence of the transistor 3 limiting the current, if a voltage is applied to terminais 5 and 6, situated at the respective ends of the two branches, that would lead to a current of 3X A in the coil 2. Since this value is much greater than the maximum permissible limit of 4 A, it. is the transistor 3 list IMISThe flowing in the coil 2, A diode 4 is connected parallel to the coil 2, The anode of foe diode 4 is connected to the dram Of the transistor 3 sod the cathode of the diode 4 is connected to the terminal % The diode 4 limits the effects of the overvoltage that appears when the second branch Is opened by the transistor ^

The transistor 3 is controlled by a control circuit,, or switch circuit., that comprises a bipolar transistor S, having its collector connected to the gate of the translstp E

The collector of the transistor S is also connected to one terminal of a resistor 12 laving its other terminal connected to tie terminal 5. The emitter of the transistor 8 is connected to the terminal 6, By way of example, the resistor 12 has a resistance of 56 kllohms fkQ).

The base of the transistor § is connected to the anode of a Zenerdiode 9 having Its cathode connected firstly to a parallel-connected capacitor Ti and resistor I t. The capacitor IS and the resistor IT connected to the terminal 8. By way of example, the capacitor IS has a capacitance of 0,1 microfarad! {pf } and the resistor 11 has a resistance of SB kfi

The cathode of the Zener diode 9 Is connected secondly to a resistor 13, itself connected to the terminal 5. By way of example, thé resistor II has a resistance of 200 kQ,

The switch arcúit operates as follows.

As soon as a potential difference is applied to the terminals 5 and 6,. a current flows In the second branch and therefore in the coil 2, and tne capacitor ID is charged via the resistor 13. When the voltage at the terminals of the capacitor reach a certain value, e,f< 111? y with the previously-given numerical values, a current flows in the transistor 8, from Is emitter to its base.

Because of the resistor 12, the electric potential of the collector of the transistor 8 and of thl gáté of the transistor 3 then falls.

The transistor 3 then opens the second branch, to such an extent that thi burrent flowing in the coil 2 is broken, after about 2 ms.

It should be observed that because the impedance of the coil 1 is higher than that Of the bbll l, the Current that flows in the cod 1 always remains low enough to be able to be broken by an auxiliary switch.

As mentioned above, the costs 1 and 2 are preferably wound on the sam# core.

That o sâtes induced currents. When the transistor 3 breaks the flow of currant in the coll 2, Sell céh induces a current In; the coif :1.. This Induced current may sere® to maintain the pé|hetíc field nedesfory for mpvingthe pongee of the mechanism. The current in the coil 2 is broken* for eeamplfo after 2 ms. This time period may he too short for the piungm'M reach its actuated final position. The current induced in the coll 1 thus makes if possible for the plunger to finish Its stroke. IP a variant the control circuit of the transistor 3 is a resistance-capacitance (HQ circuit, in this event., a capacitor Is connected between the terminal S and the gate of the transistor 3.. and a resistor is connected between the terminal δ and the gate of the transistor 3. Their resistance and capacitance are selected so that the R€ time-constant is equal to a determined value* e.g, 2 ms. it should be observed that the Invention not only finds application in a gas-insulated substation (GiS), but also in other types of connection equipment,, e.g. ait-insulated switchgear, Of dead-tank oil circuit-breakers, for use indoors or outdoors.

Claims

paöadsiml igénypontok t. Működtető áramkör megszakító vezérlésére, amely tartalmaz kit párhuzamos ágét kit csatlakozó kapocs (5, ö) között, ahoi az első ág csak egy első tekercset (1) tartalmaz, és a második ág egy második tekercset (2) tartalmaz, az elsőnél alacsonyabb Impedanciával, egy kapcsoló áramkörrel (3) vezérelt kapcsolóval sorhaköive,
2, Az 1, igénypont szerinti működtető áramkör, azzal Jellemezve, hogy a kapcsoló áramkör kialakításánál fogva korlátozza a második tekercsen {2} átfolyó áramot, és nyitja a második ágat egy előre meghatározott idő elteltével, miután egy feszü ltség különbség kérőit a két csatlakozó kapocsra (S, 6). 3v Az i, vágy 2. Igénypont szerinti működtető áramkör, azzal jellemezve, hogy a kapcsoló (3) egy térvezérlésű tranzisztor, egy NPN átmeneti tranzisztor, égy tirisztor vagy egy mechanikus relé közül kiválasztott alkatrészt tartalmaz,
4, Az 1 - 3. igénypontok bármelyike szerinti működtető áramkör, azzal jellemezve, hogy az első és a második tekercs (i, 2) ugyanazon magra van tekercselve, s, Megszakító vezérlő (21), amely az 1 - 4, igénypontok bármelyike szerinti működtető áramkört tartalmazza, I, Megszakító (20) amely tartalmaz egy 5, Igénypont iz^lo^möklki^tlliáramkőrt tartalmazó vezérlőt.