GB191113099A - Improvements relating to the Generation of Alternating Electric Current. - Google Patents

Abstract

13,099. Rosenberg, E. May 31. Systems depending on the use of two or more machines.-One of a pair of s y nchronous generators is driven by an engine, while the other is driven by a turbine supplied with exhaust steam from the engine. The generators are normally connected, a single switch controlling the connexion to and disconnexion from the bus-bars, and means are provided to synchronize automatically the generators while running up to speed. In the arrangement shown in Fig. 1, the generators 1, 2 are permanently connected at the points 6, a single switch 7 controlling the connexions between the generators and the busbars 3. The field windings 4, 5 of the generators are connected in parallel across a directcurrent source 8; in a modification, the windings 4, 5 are connected in series, one of them being regulated by a shunt resistance. When the exciter of the machines is driven by the engine of one of the generators, damping windings are placed on one or both machines which cause one of them to act similarly to an induction motor and become synchronized with the other machine. In a modification, massive poleshoes are employed. In the arrangement shown in Fig. 3, the engine-driven generators 1 are excited from bus-bars 15, which are not capable of supplying the field windings 5 of additional machines 2 driven by turbines. In this case, the field windings 17 of separate exciters 16 are connected in parallel with the field windings 4. of machines 1; or they may be connected, in series with these field windings. Switches 19 may be placed between the machines 1, 2 as shown in Fig. 3, to facilitate inspection and repairs.