US2231736A - Vapor electric device - Google Patents

Description

Feb. 11, 1941. H. A. Ros: 223L736 VAPOR ELECTRIC DEVICE Filedlkpril 15, 1939 INVENTOR I flerberf/Z'Eose ATTORNEY Patented Feb. 11, 1941 UNITED STATES 2.231336 VAPOR ELECTRIC DEVICE- Herbert A. Rose, Leonia, N. J., assignor to Westinghouse Electric & Manufacturing Company, East Pittsburgh, Pa., a corporation of Pennsylvania Application April 13, 1939, Serial No. 267,630

4 Claims.

My invention relates to a vapor electric device, and particularly to a control system for a vaporelectric converter such as a high voltage ignitron.

In the operation of vapor electric devices, it has been discovered that the internal pressure in such devices can be considerably lowered by running a preliminary arc prior to the operation of the devices. This preliminary arc in the converter devices materially reduces the dangers of backfire and other faults at the beginning of the operating periods. While the reason for this reduction in pressure is not definitely known, it is believed that the action of the arc probably excites chemical reactions of some sort whereby remnant gases combine to form compounds of less volume with consequent lowering of pressure in the vacuum chamber.

I propose to make use of this phenomenon by supplying a control system which will initiate an arc, preferably to the exciting electrodes, for a predetermined interval before the application of potential to the main electrodes of the converter.

According to my invention, this is accomplished by providing an exciting system capable of maintaining at least for brief periods an arc in the converter chambers and to provide a control system by which the excitation system is energized a predetermined interval before the closing of the main breakers to energize the principal electrodes of the converter. I

It is, accordingly, an object of my invention to provide a converter system in which a clean-up arc will be maintained for a predetermined interval prior to placing the converter in service.

It is a further object of my invention to provide a control system having automatic mechanism for determining the application of excitation energy and the main converter energy.

Other objects and advantages of my invention will 'be apparent from the following detailed de scription taken in conjunction with'the accompanying drawing, in which the single figure is a schematic illustration of a vapor electric converter according to my invention.

In the illustrated embodiment of my invention, energy is fed from an alternating current circuit I through a coupling transformer 2 to a direct-current circuit 3, the flow of current through the coupling transformer 2 being controlled by a multi-valve converter 4 herein illustrated as of the ignitron type, in which each of the valves 5 is enclosed in an independent arc chamber 6. Each of the arc chambers 6 comprises a vaporiz able cathode 1 preferably of mercury, gallium 'or other reconstructing material, and a suitable anode 8 cooperating therewith.

The excitation system comprises a make-alive electrode 9 for each of the ignitron valves 5, the make-alive electrodes 9 being fed by a suitable supply system, preferably of the type in which the duration of the impulse to the make-alive electrodes 9 can be regulated at will, as shown in my prior Patent No. 2,130,902. The direct-current circuit 3 is preferably provided with the usual high speed circuit breaker l2 herein schematically illustrated.

The flow of potential to the main electrodes 1 and 8 of the converter 4 is controlled by means of the usual breaker 52, while the flow of the potential to the excitationsystem is provided by means of a circuit breaker 53. The control system provides a suitable source of direct-current such as the battery l feeding the bus bars II and I2. An operating relay l3 has its operating winding l4 connected across these bus bars H and I2 and is controlled by means of push buttons l5 and [6 which obviously may be adapted for either manual or remote control as may be desired. By closing the push button l5 in series with the operating coil M of the operating relay l3 and providing the operating conditions of the converter are normal as shown by the closing of the safety switches [1, the control relay l3 will close its contacts lockingitself in and energizing a control circuit which closes circuit breaker 53 energizing the excitation system and establishing the clean-up arcs in the vacuum chambers 6. Simultaneously with the energizing of the control circuit to the breaker 53, the time control relay will be energized. After a predetermined interval, the time control relay [8 closes its contacts l9 and energizes an operating relay 2| which, in turn, energizes the main breaker 52 controlling the supply of energy to the anodes 8 of the converter 4.

For purposes of simplicity of the illustration, the anti-pump relays, checking relays and other incidentals to a normal rectifier system have been omitted. However, it will be understood that such normally supplied relays are necessary for an operating system. For the same reason relay [9 is shown as provided with a dash pot to control the time of operation although any type of timing relay may obviously be utilized.

In order to place the system in operation, the push button I5 is operated, which, if the supervision controls are in normal position, will energize the coil M of the control relay l3 which closes its contacts, one of which looks itself in.

Closing of the contact l3 energizes the closing coil 53a of the contactor 53 energizing the makealive circuits. The make-alive electrodes 9 initiate the cathode spot of an arc and the control device is being adjusted to provide a long application of starting current. The arc will be transferred to the holder 25 of the make-alive electrode or if preferred an auxiliary electrode can be provided for the attachment of the clean-up arc. Simultaneously it also energizes the primary of the timing relay 18 which starts to operate. After a predetermined interval, the timing relay l8 closes its contact l9 which energizes the operating coil of the operating relay 2|. The operating relay energizes the closing coil 52a of the breaker 52 which closes, its contacts energizing the anodes 8 of the rectifier 4.

To shut down the system, the push button [6 is operated, shorting the operating coil l4 of the control relay l3 which opens its contacts, deenergizing the breaker 53 which removes the excitation and at the same time deenergizes the timing relay l8 which drops out deenergizing the operating relay 2| which, in turn, opens the holding circuit of the breaker 52.

While for purpose of illustration I have shown and described a specific embodiment of my invention, it will be apparent that my system is applicable not only to ignitron type converters but to multi-anode converters or any other vapor electric devices in which it is desirable to maintain a clean-up are preliminary to the initiation of the main arcs therein.

I claim as my invention:

1. An electric current conversion system for transferring energy between electric current circuits comprising a plurality of make-alive type electric valves, each valve including a plurality of main electrodes and a make-alive electrode, main circuit breaker means for controlling energization of the main electrodes of said valves, a source of potential for said make-alive electrodes, circuit breaker means for controlling the energization of said make-alive electrodes, a control relay, means for controlling the energization of said control relay, circuit means energized by said control relay for operating said circuit breaker means to energize said make-alive electrodes and to es tablish a clean-up arc in said valves, a time delay relay energized by said control relay, said time delay relay operating a predetermined time after the establishing of said clean-up arc to operate said main circuit breaker means.

2. An electrical conversion system for transferring electrical energy, an alternating and a direct current circuit comprising transformer means interconnecting said circuit, a plurality of make-alive type valves for controlling current flow between said systems, each of said valves including two main electrodes and a make-alive electrode, a source of exciting current for said make-alive electrodes, circuit breaker means for controlling said source of exciting current, a second circuit breaker means for controlling energizationof said transformer means, a control relay, circuits energized by said control relay for actuating said first mentioned circuit breaker means to energize said make-alive electrodes for establishing clean-up arcs in said valves, a timing relay energized by said control relay, circuit means energized by said timing relay for energizing said second circuit breaker means to energize said transformer means, a predetermined interval after the establishing of said clean-up arcs.

3. A vapor electric conversion system for transferring electrical energy between two electrical circuits comprising a plurality of arc type valves, each of said valves having a main anode and mercury cathode, an exciting electrode cooperating with each of said cathodes, a main source of electric current, an auxiliary source of electric current, means for connecting said auxiliary source of current to said exciting electrodes for establishing clean-up arcs in each of said valves and means for connecting said main source of current to said main anodes a predetermined interval after the establishment of said clean-up arcs.

4. A vapor electric system comprising a plurality of vapor electric valves, each valve including an anode and a mercury cathode in an evacuated chamber, a make-alive electrode for each of said valves, a source of main power energy for said valves, a main switching device for connecting said source to said valves, an auxiliary source of current, an auxiliary switching device for connecting said auxiliary source of current to the make-alive electrodes, a control device for actuating said auxiliary switching device to establish a clean-up arc in each of said valves and relay means energized by said control device for closing said main switching device a predetermined interval after the establishment of the clean-up arcs.

HERBERT A. ROSE.

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