GB458132A - Improvement in and relating to the control of series electric motors - Google Patents

Abstract

458,132. Master control of motors. MALEY, A. W., 4, Grosvenor Road, Handsworth, and TAUNTON, E. M., 90, Fitz Roy Avenue, Harborne, both in Birmingham. June 18, 1935, No. 17519. [Class 38 (iii)] In a control system for series motors including contactors for effecting the speed control, the windings of the contactors are connected in turn across a field winding of the motor by means of a master controller. The contactors cut resistances out of the motor circuit and do not interrupt the field circuit when they operate. The field of the motor may comprise a principal section 2 carrying, say, nine-tenths of the motor current and an auxiliary section 4 carrying one-tenth of the motor current. By operation of the master controller 13 the contactor windings 11, 9, 7, 5 are connected in turn in series with the field section 4 and across the field section 2 and such part of the series resistance 3 as is in circuit. The operation of the contactors cuts out the resistance 3 in steps. The windings 11, 9, 7, 5 may be connected in parallel instead of series and the resistance 3 may be outside the energizing circuit for the contactors. Alternatively, the motor field may be divided into four equal sections and the contactor windings energized by insertion one in series with each of the field sections. In a further alternative arrangement the motor field is in a single section across which the contactor windings are successively connected. For remote control the drum controller 13 may be replaced by a contactor panel operated by a distant control drum, or, in the case of railway vehicles the contactors may each have an additional contact arm controlling contactors on another coach. Specifications 430,029 and 434,189 are referred to.