Patent GB-190822044-A (GB)
Title: Improvements in Arrangements for Storing and Distributing Alternating Currents of Electricity.
Inventor: TAYLOR ALFRED MILLS
Filed: 1908-10-19
Granted: 1909-10-19
Abstract: 22,044. Taylor, A. M. Oct. 19. Distributing.-In an alternating-current supply system, the central station is disconnected automatically at certain hours, and the supply is maintained by accumulators at the substation. The main supply is re - connected automatically or manually at a time controlled from the central station. The primary of a transformer e is connected to the high-tension mains a through the switch l, and the secondary to the low-tension mains b through the switch k and to the motorgenerator d through the switch j. The motorgenerator is employed for charging and discharging the battery c. The oil switch l is operated by a motor or electro-magnet when the actuating-circuit is completed by the time switch t. The time switch also closes contacts in the circuit of a warning-bell before the switch l is operated. After the warning, the machine d is started as a directcurrent motor supplied by the battery c, by means of a rheostat h in the armature circuit. The speed can be varied by means of the field rheostat i until the current in the alternating-current side of the motor-generator is in synchronism with the hightension current as denoted by the volt-meter V across the switchj. The switch j is then closed to put the alternating-current side of the machine d in parallel with the alternating-current system a to supply the circuit b. The oil switch l is opened by a trip-coil energized through a time switch, and the battery c continues to supply the energy for the circuit b. The switch k is also opened to prevent the motor-generator from supplying current to the transformer e. When the circuit b is to be supplied from the central station again, a second operation of the time switch closes the switch l. The speed of the machine d is again varied until its alternating current is in synchronism with the main supply ; the switch k is then closed, and its field is varied by the rheostat i until the load of circuit b is removed from the motor-generator. The switch j is then opened, and the motor-generator can be shut down. In a modification, a rotary converter is used instead of the motor-generator, and an additional transformer is employed in conjunction with it. The ratio of transformation of the additional transformer may be varied by a triplepole switch in the secondary windings, as described in Specification No. 22,581, A.D. 1907. In a further modification, a motor-converter is used, and regulation is effected by the transformer ratiochanging-switch. An automatic switch similar to that described in Specification No. 17,814, A.D. 1905, may be used instead of the time switch t. The Provisional Specification states also that when a motor-converter or a motor-generator is used, sections of the stator winding may be connected for series-parallel regulation, and the direct-current side of the motor-generator or rotary-converter may consist of two windings capable of being connected in series and parallel ; also that an externally-operated controller may be used to connect the sections of the transformer primary in series and parallel.