GB745767A - Motor generator power system - Google Patents

Abstract

745,767. Exciting dynamo-electric machines. PESTARINI, J. M. Nov. 10, 1954 [Nov. 10, 1953], No. 31163/53. Class 35. [Also in Group XXXVII] One or more, parallel connected cross-flux generators A, C, providing a constant current irrespective of speed, feed one or more crossflux motors E, F, G, which run at constant speed irrespective of load under the control of exciters M, N, S, bucked by a battery 1 to give a critical excitation of control windings 21, 31, 41. Each generator has control windings 2, 5, 6 or 12, 15, 16 on the primary axis a, c and windings 3, 4, 7, 8, 9 or 13, 14, 17, 18, 19 on the secondary axis b, d. The primary brushes are connected in a low resistance circuit including the battery 1, while the secondary brushes may be connected to the load by switch Y1. Field windings 2 and 3 and 12, 13 are connected to produce an E.M.F. opposing the current flowing in them, thus stabilizing the operation of the generator. Windings 4, 5 and 14, 15 provide a constant excitation from the battery 1 through rheostats X1, X2; winding 6, 16 provides a shunt excitation; winding 7, 17 provides partial secondary current armature reaction compensation; windings 8, 9 and 18, 19 are further shunt windings fed from the primary and secondary brushes respectively. The effect of these windings is to cause the generator to supply a fixed current as controlled by rheostat X2 irrespectively of the load voltage or generator speed. The motors are provided with windings 20 and 22 on the secondary axis carrying the load current and secondary current respectively. Primary axis windings 21, 23 are energized respectively by a speed sensitive generator M on the same shaft and bucking the voltage of battery 1, and by the primary current, by which it serves to compensate for armature reaction. Winding 22 may be dispensed with and brushes b, d simply connected together, while winding 20 may be disconnected at Y4 when the motor is up to speed. Several motors may be synchronized by means of three-phase armature connections or by driving separate three-phase generators. If desired, the effect of the speed sensitive generator may be made more marked in regulating the speed by the use of an amplifying generator 5 as shown for machine G. Specification 420,167 is referred to.