GB400772A - Improvements in and relating to control system for low pressure gaseous electric discharge apparatus - Google Patents

Abstract

400,772. Converting. AKT.-GES. BROWN, BOVERI, ET CIE, Baden, Switzerland. Oct. 24, 1932, No. 29744. Convention date, Oct. 24, 1931. [Class 38 (ii).] In arrangements for rectifying A.C. or for converting D.C. to A.C. and for similar purposes in which current is transmitted through arc discharge apparatus having provision for blocking the anode-cathode path for a predetermined period, the ignition voltage is raised above the normal operating voltage by means of negatively charged grids and ignition is effected at a predetermined moment by applying a high voltage to the anodes. In the rectifying arrangement shown, the grids are negatively charged by a battery 2 and high voltage ignition impulses are applied to the anodes from a condenser 5 which is alternately charged from a D.C. source 7 through contacts 10 of a rotary distributer and discharged through contacts 9 connected to the anodes of the rectifier. Alternatively the anodes may be ignited by high voltage impulses produced by spark discharge. Inductances 8 are introduced into the anode leads to prevent dissipation of the ignition impulses through the supply transformer. The grids, instead of being continuously negatively charged, may be connected to anodes of lagging phase so as to render the anodes under their influence non-conducting until an ignition impulse is applied. The Specification as open to inspection under Sect. 91 states also that ignition voltage may be raised above the operating voltage by narrowing the anode shields, building structures into the shields, or using a weak magnetic field to divert the electrons. This subject-matter does not appear in the Specification as accepted.