DD218708A2 - METHOD FOR LOADING A SHIFT ARC IN ELECTRIC SWITCHES - Google Patents

Abstract

THE INVENTION RELATES TO A METHOD FOR DELETION OF SWITCHING ARC IN A GASGEFUELLTEN LOESCH CHAMBER OF ELECTRIC SWITCH FROM WHICH THE REDUCTION OF THE ELECTRICAL CONDUCTIVITY OF SWITCHING ARC PLASMA BY EFFECT IS THAT IN CONTROL MEDIUM BEFORE SHUTDOWN by external or internal AGENTS OR / AND BY THE ENERGY CONTENT OF BURNING CONTROL ARC A PRESSURE INCREASES UP TO A VALUE THAT IS OUTSIDE THE INSTABILITY AREA OF A NON-IDENTAL PLASMA, AND THEN A NEGATIVE PRESSURE PULSE IS RAISED. THE OBJECTIVE OF THE INVENTION IS TO OBTAIN A NEGATIVE PRESSURE PUMP WITH THE MINIMUM OF EFFORT AT THE REQUIRED TIME, AND ALSO IN SMALL STROEMES TO BE TURNED WITHOUT ELAPS. ACHIEVED THIS BY VOLUMENVERGROESSERUNG THE CLEAR CHAMBER AND / OR BY A DEFINED PRESSURE REDUCTION IN THE CLEAR CHAMBER BY THE VOLUMENVERGROESSERUNG THROUGH OUT MOVEMENT OF ONE OR BOTH CONTACT FROM THE CLEAR CHAMBER IS AND DEFINED PRESSURE REDUCTION IN THE CLEAR CHAMBER OF EXPANSION OF CONTROL MEDIUM via a controllable valve CARRIED OUT.

Description

Title of the invention

\ Method to delete a Schal.tlichtbogens in electric, switches.

Field of application, the invention

The invention, which is effective in the field of electric power supply, relates to a method for extinguishing a switching arc in a gas-filled quenching chamber of an electrical switch, in which before and / or v / hd. a switching operation by internal or external means and / or by the free energy of the burning switching arc in the quenching chamber a pressure increase is brought up to a value lying above the instability range of a non-ideal plasma value and after reaching the required pressure and temperature values during the switching operation such negative, is applied to the nichtideale plasma, each of the Gas.abhängiger pressure pulse applied that a phase transition from a plasma with high electron density above the instability region to a lower, below the instability range lying electron density occurs, according to WP 1 0 0 3 CZ

Characteristic of the known technical solutions

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For the realization of high switching power with a switching path at the same time, with a low energy consumption

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within the passage of the stream possible extinction. se hung 'a switching arc without re-ignition of the arc by the recurrent voltage is according to the patent application W? H 01 H / 227 319 has been proposed, before or / and during the switching operation by internal or external means and / or by the free energy of the burning switching arc in the quenching chamber, to increase the pressure to a value above the instability range of a non-ideal plasma and after applying the required pressure and temperature values during the switching operation to apply such a negative, depending on the particular gas pressure pulse applied to the nichtideale plasma, that a phase transition from a plasma with high electron density above the instability zu.einem with lower, below the Although this method achieves, in connection with the negative pressure pulse, that the electrical conductivity of the arc plasma is reduced to the required order of magnitude, no further method step is required e shows how the negative pressure pulse is to be introduced in detail after a pressure increase in the quenching chamber has been brought up to a value above the instability range of a non-ideal plasma.

Object of the invention

The aim of the invention is to cause with the least effort sum required time a negative pressure pulse, even in small, without power interruption to be switched currents »

Explanation of the essence of the invention

The invention is based on the object, in a method for deleting .Aes switching arc in a gas-filled quenching chamber of an electrical switch, according to W? H 01 H / 227 319, the negative, depending on the particular gas pressure pulse applied to the non-ideal plasma, after previously. and / or during a switching operation in the quenching chamber, a pressure increase was brought up to a value lying above the instability range of a non-ideal plasma, to achieve components already existing or known per se in such electrical switches. ...

According to the invention therefore applied to the non-ideal plasma negative pressure pulse is caused by an increase in volume of the quenching chamber and / or by a defined pressure reduction in the quenching chamber by the increase in volume takes place by moving one or both contacts out of the quenching chamber and the defined pressure reduction in the quenching chamber by expansion of the switching medium via a fast, controllable discharge valve «

If the negative pressure pulse applied to the non-ideal plasma is brought about by a defined pressure reduction in the quenching chamber by the pressure reduction in the quenching chamber taking place by expansion of the switching medium via a fast, controllable discharge valve, the initial stationary pressure is produced after each switch-off operation via a further valve remade in the quenching chamber.

The defined pressure reduction by expansion of the switching medium via the fast, controllable discharge valve serves essentially to provide a high-voltage circuit breaker using the method according to the invention,

which controls all internationally-specified switching film ¹ ·. Because, for example, to be able to switch small (inactive) currents without current interruption, it is necessary to lower the plasma pressure in the quenching chamber in a defined manner. It follows that the opening duration of the ~ fast, controllable discharge valve is determined as a function of the steady-state pressure in the quenching chamber.

Of course, it is necessary that when .Verwirklichung the inventive method of the movable contact - come two movable contacts for use, it is the same for both - is secured in the two end positions by an automatic mechanical locking and unlocking. Only after unlocking the Bewegungsprozeß.des contact to initiate.

Exemplary embodiment.

The invention will be explained in more detail below by means of two Ausführungsbeispielen-. ⁷ In the attached drawings show:

1 shows a section of a high-voltage circuit breaker in which the negative pressure pulse is produced by an increase in the volume of the quenching chamber;

Pig. 2 shows a section of a high-voltage circuit breaker in which, in addition to the increase in volume, a defined pressure reduction in the quenching chamber is carried out in order to produce the negative pressure pulse.

At the beginning of the extinguishing process, the high-voltage power switch switches to Pig. T the contacts 1; 2 separately without noticeably increasing the volume of the extinguishing chamber 3. The pressure and the temperature are created by the resulting arc ^! until 'increased to the necessary starting values. Thereafter, a controlled increase in volume is initiated by

Move the movable contact 2 is reached from the quenching chamber 3. In the high pressure resistant extinguishing chamber. 3 is a selected switching medium (eg., Gas) under an initial pressure P., and a temperature T- · The extinguishing chamber volume V- (x) is dependent on the position of the movable contact 2. The drive of the movable, contact 2 by a volume Vp by the pressure Pp. With a control valve 4- is adjustable. This controllable volume Vp is located in a high-pressure drive part 5 * For the closing operation of the switching path is at a closed control valve 4 via a further valve 6 from a Hochdruckvorratstank 7 Gas.entnommen, so that P ₂ > P ₁ . ,

So that the gas can not flow in the direction of the high-pressure storage tank 7 during shutdown, is located behind the baffle 8, a check valve 9 »If start the shutdown at a defined time, the coil TO of the control valve 4 must be controlled, otherwise by the pressure spring 11 the volume Vp remains closed. Only when current flows through the coil 10, the control valve 4 opens, so that Pp «= rP-, whereby the movable contact 2 moves out of the quenching chamber 3. Shortly after disconnecting the contacts 1; 2, an arc in the quenching chamber 3, whereby the initial pressure P- is increased by a factor, but which is essentially dependent on the Abschaltstrom and the switching medium of the quenching chamber 3. At zero current passage occurs a significant cooling of the plasma in the quenching chamber 3 and at simultaneous enlargement of the chamber volume V-, by moving out of the moving contact 2, the intended plasma phase transition occurs. It thus comes to a very rapid reduction in the charge carrier density, so that a reignition of the switching arc is prevented. Thus, it is possible to successfully extinguish a switching arc at the current zero crossing, without a blowing of the switching path is necessary.

In thy high-voltage circuit breaker according to "Pig, 2 again an increase in volume of the chamber 3 by the movable contact 2 is moved out of the quenching chamber 3 to effect the negative pressure pulse occurs. In addition, however, a defined pressure lowering-in of the chamber 3 is by expansion of the switching medium via the fast, controllable discharge valve 12 is provided, the opening duration of which is determined as a function of the steady-state pressure in the extinguishing chamber 3. If the switch-off process is ended, the original stationary pressure in the extinguishing chamber 3 is re-established via a further valve 13. The switching medium can For this purpose, either taken from the high-pressure reservoir tank 7 or removed from a further, not shown high-pressure vessel .This in turn can be refilled by re-compression of the switching medium with a compressor., Which the intercepted switching medium from a likewise not shown container after outflow via the fast, controllable discharge valve 12 reused.

Claims (3)

invention claim 1. A method for deleting a switching arc in a gas-filled quenching chamber of an electrical switch, at your before and / or during a switching operation by internal or external means and / or by the free energy of the burning Scnaltlichtbogens in the quenching chamber pressure increase to one above the instability region a non-ideal plasma lying value is brought about and after reaching the required. If pressure and temperature values during the switching process are applied to the non-ideal plasma in such a way that is dependent on the particular gas used, a phase transition from a plasma with a high electron density above the instability range to an electron density lower than the instability range will occur , according to Pd1er> f {03G3, characterized in that the negative pressure pulse applied to the non-ideal plasma is brought about by an increase in volume of the quenching chamber and / or by a defined reduction in pressure in the quenching chamber, by increasing the volume by moving one or both contacts out of quenching - • Chamber takes place and the defined pressure drop in the quenching chamber is made by expansion of the switching medium via a fast, controllable discharge valve. 2. Verfahren.nach point 1, characterized in that at a defined pressure reduction · in the quenching chamber by expansion of the switching medium via a fast, tax- , Bares outflow valve after each shutdown via another valve, the original stationary pressure in the quenching chamber is re-established. 3. The method according to item 1 and 2, characterized .dadurch that the opening duration of the fast, controllable discharge valve is determined in dependence on the steady state pressure in the quenching chamber,. For this A rare drawings