SU649180A1

SU649180A1 - Power supply source

Info

Publication number: SU649180A1
Application number: SU762423859A
Authority: SU
Inventors: Сергей Викторович Кашлачев; Юрий Яковлевич Киселев; Альфред Никодимович Лещинский
Original assignee: Тираспольский Завод "Литмаш" Им. С.М.Кирова; Кишиневский Политехнический Институт Им. С.Лазо
Priority date: 1976-11-24
Filing date: 1976-11-24
Publication date: 1979-02-25

Description

II

Изобретение относитс к отрас;ш электротехники и может использоватьс в электротехнических плазменных установках различного назначени , в частности в установках дл воздушно-плаэменной резки металлов.The invention relates to the field of electrical engineering and can be used in plasma electrical installations for various purposes, in particular in installations for air-flame cutting of metals.

Известен источник питани сварочной дута переменного . Вследствие большой посто нной времени сглаживающей цепи , включенной между выходными клеммами источника питани , крутизна нарастани тока и величина напр жени на сглаживакшем конденсаторе недостаточны дл надежного формировани дугового разр да, этот не- достаток особенно сильно про вл етс в плазмотроне с воздушной стабилизацией дуги.A known power source for welding duo is variable. Due to the long time constant of the smoothing circuit connected between the output terminals of the power source, the steepness of the current rise and the voltage on the smoothing capacitor are not sufficient for reliable arc generation, this deficiency is particularly pronounced in the plasma jet with air arc stabilization.

Наиболее близким техническим решением к предлагаемому изобретению вл етс источник питани плазмотронов с независимой дугой на переменном токе , примен ющийс дл сварки и напылени 2.The closest technical solution to the present invention is a plasma torch power source with an independent alternating current arc used for welding and spraying 2.

Этот источник питани содержит силовой трансформатор, защитный конденсатор , высокочастотный генератор, вы сокочастотную индуктивность, включенную последовательно в силовую цепь.This power source contains a power transformer, a protective capacitor, a high frequency generator, a high frequency inductance connected in series to a power circuit.

При изменении направлени тока дута возбуждаетс импульсами высокочастотного генератора. В момент возбуждени плазменной дуги цепь, состо ща из защитного конденсатсфа, высокочастотной индуктивности и плазменной дуги , образует колебательный контур. В результате переходный процесс тока дуги носит колебательный характер.When the current direction is changed, the blower is excited by pulses of a high-frequency generator. At the moment of excitation of the plasma arc, the circuit consisting of a protective condensate, high-frequency inductance and plasma arc forms an oscillating circuit. As a result, the transient process of the arc current is oscillatory.

Положительным эффектом такого переходного процесса вл етс больша первоначальна крутизна нарастани тока, отрицательным - переходы тока через ноль, при которых дуга гаснет.The positive effect of such a transition process is a large initial steepness of the current rise, a negative one is the current zero crossing, at which the arc goes out.

Claims

In order to eliminate this drawback, it is possible to increase the cruise-current rise of the power current, increasing or the open-circuit voltage of the power transformer or the magnitude of the flux-coupled power transformer. The increase in the flux chain is limited by the maximum allowable value of vortex current. Therefore, in order to reliably ignite the AC arc, it is necessary to scatter the no-load voltage of the power supply source several times, which leads to an increase in its dimensions, and the danger of electrical personnel damaging the operating personnel increases. The purpose of the invention is to increase the reliability of the plasma arc of alternating current and reduce the no-load voltage of the power source. This is achieved by the fact that a sequential oscillating circuit is introduced into a power source containing a power transformer, a protective capacitor, a high-frequency generator, a high-frequency inductance, connected in series to a power circuit. The figure shows schematically the proposed power source. It has a power transformer 1, in parallel with which a protective capacitor 2 is connected and a series oscillating circuit consisting of a storage capacitor 3, a damping resistance 4 and a throttle 5, a high frequency generator 6 with a control unit 7, an output transformer 8, the secondary winding of the latter high-current inductance connected in series to a power circuit. When a plasma arc is ignited in a complex oscillatory circuit formed by a protective capacitor 2, a series oscillatory circuit, the secondary winding of the output transformer 8, the high-frequency generator 6 and the plasma arc 9, a transient oscillatory process occurs. This transition process is characterized by a steep rising edge of the current and does not have zero crossings. The parameters of the series oscillating circuit are selected so that the voltage on the capacitor of the serial oscillating circuit at the end of the recharging process is as high as possible, and on the other hand the transient oscillating process of the arc current does not have zero crossings. In this case, the plasma arc reliably ignites at a small value of the no-load voltage of the power supply. The use of a new element — a sequential oscillatory circuit — will allow, with a relatively simple scheme, to maintain a reliable plasma arc of an alternating current with a small idle voltage of the power supply, resulting in a reduction in the size of the power supply and an increase in the efficiency of service. The invention The power source, mainly for plasma cutting with alternating current, contains a power transformer, a high-frequency generator, a high-frequency inductance connected sequentially to a power circuit, a protective capacitor, characterized in that, in order to increase the reliability of the plasma of an alternating current and reduce the voltage idle power source, a sequential oscillatory ontur is introduced into it. Sources of information taken into account in the examination 1. German patent, N92H9135, cl. At 23 K 9/10, 14.03.74.

2. The patent of Switzerland No. 546О27, cl. H 05 H 1 / OO, 1975.

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