DE1514322A1 - Arrangement to improve the ignition and stability of induction plasma torches - Google Patents

Description

Philips Patentverwaltung G.m.b.H. ', Hamburg 1, Monokel) ergs tr. 7

Arrangement to improve the ignition and stability of

Induction plasma torches

The invention relates to an arrangement for improving the
■ Ignition and to increase the stability of induction plasma torches.

With such plasma torches it is common to connect the inductor directly to the HP output of a generator. Included
the HP current flowing through the inductor is almost constant. The reactive power in the inductor is also very low, so that ignition has to be initiated by the action of a premade, for example by an electric arc.

If the gas supply is changed, manual readjustment of the Generator coupling required to trigger the overcurrent relay or even to prevent the plasma from going out "

Here, a between the decoupling coil and the inductor can be

PHD-O94

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BATH

switched variable impedance, "for example an adjustable capacitor, serve to change the performance, as it is known, for example, from French patent specification 1 371 963 ".

The above night rush, namely the need for one Premd effect for ignition as well as the manual coupling change, are according to the invention in an induction plasma torch with a capacitance between the coupling coil and the inductor avoided by dividing the said capacity into two partial capacities, one of which is known Way in series and the others in parallel to the inductor and both capacitances together with the inductance of the inductor are tuned to the resonance frequency ο

In this way, on the one hand, there is a much higher reactive power, which is always sufficient to initiate the ignition, on the other hand also achieved a considerably better stabilization.

A change in the capacities can take place, for example, by connecting or disconnecting additional capacities while the inductance of the inductor e.g. B. by changing the Windungsabs "tied it can be influenced.

It is expedient to place the operating point on the inductive one Branch of the resonance curve, because it not only reduces the voltage at the inductor after the ignition has taken place due to the increased Attenuation a further reduction occurs by reducing the inductance »

The figure shows a conventional generator 1, its HP energy decoupled by the coil 2 and that from the series capacitance 3, the inductor 4 and the capacitance connected in parallel with it 5 formed resonance circuit is fed

Duroh capacities 3 and suitable choice of ratio

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to one another also allows the working of the arrangement to be influenced « So a relatively high capacity 3 gives a "hard" one, a small capacity 3, on the other hand, allows the burner to work "softly" ο A "medium" way of working - was z. B. then achieved when the ratio of the two capacities is about 1: 1.

Claims

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Claims (3)

15U322 patents, epr üohe 1. Arrangement to improve ignition and stability an induction plasma torch with an e as above Coupling coil and inductor lying capacitance, characterized in that said capacitance in swei l'eilkapaeititäten (3.5) is divided, one of which (3) in a known distance in series and the other (5) of which are parallel to the inductor (4) and both capacities alt the inductance of the inductor (4) are matched to the resonance frequency 2. Arrangement according to Anepruoa 1, thereby gekenmeiohnet that the lapasities (3 »5) and / or the inductance (4) can be reranded * 3. Arrangement according to claim 1 or 2, characterized gekenaseiohnet, that the two chapters (3.5) are about the same size. 4 · Arrangement according to one of the recommendations 1 to 3 » knows that the coordination on the inductive branch the Reeonanikurre takes place 909836/057 0 BAD ORiQlNAL