GB425898A - Improvements in and relating to electric motors - Google Patents

Abstract

425,898. Motors. BRITISH THOMSONHOUSTON CO., Ltd., Crown House, Aldwych, London.-(Assignees of Allgemeine Eloktricitõts-Ges.; 2, Friedrich Karl-Ufer, Berlin) Aug. 24, 1933, No. 23605. Convention date, Aug. 24, 1932. [Class 35] Machines with vapour rectifiers in place of commutators.-In a motor of this type the winding has two or more pairs of phases or tapping points each connected to the midpoints of two separate secondary windings of a transformer, both the anodes to which the two end points of the individual secondary windings are connected appertaining to the same discharge vessel, and the transformer winding is connected to a polyphase supply. In the form shown in Fig. 1, the transformer secondaries 11... 13<1> are connected to the anodes 21...23<1> and through inductances to the motor windings 31...33<1>. In a modified form, three inductances are connected to pairs of phase windings to form the neutral point and are in the circuit of the field winding 30. In the form shown in Fig. 5, the windings are arranged in ring formation and connected to transformer secondaries, the corresponding anodes of which are in two vessels 2, 21. The field winding may be separately excited through an additional rectifier. The transformer primary winding may be star or delta connected, or if subdivided, star-delta, or zig-zag connections may be employed.