Improvements in and relating to the electric propulsion of ships

摘要

450,086. Transmitting mechanical power. AKT.-GES. BROWN, BOVERI, & CIE, Baden, Switzerland. Nov. 8, 1934, No. 32204. Convention date, Nov. 8, 1933. [Class 38 (iv)] [See also Group XXIXI In a ship propelling system in which one or more generators supply one or more propeller motors, the speed of revolution of a disconnected and unloaded generator is dependent upon the speed of a motor. In the system shown in Fig. 1, either or both of the generators cl, c2 each driven by a turbine d1, d2, supply current through switches A1, A2 to a synchronous motor a, the control being effected by hydraulic means. The steam supply to the turbines is regulated by valves g1 g2 operated by pistons i1 i2 which are closed by springs and opened by oil pressure supplied through pipes 21, 22 from pumps k1, k2. The pressure of oil is regulated by leakage valves o1, o2 adjusted jointly by oil pressure in a pipe I supplied from a pump t and having a leakage control valve f. A further control of the operating pressure in the pipes 21, 22 is effected by centrifugal governors h1, h2 driven by the turbines and a governor m driven by the motor a. Each governor adjusts vertically a piston u1 or u2 co-operating with an opening in the wall of a sleeve which is forced downwardly by a spring and raised by oil pressure in the pipes 31, 32 under the control of leakage valves r1, r2 regulated by pressure in the pipe II under the control of a speed governor m driven by the motor a. The valve f thus controls the speed of either or both generator, while the governors h1, h2 limit their maximum speed in dependence upon the speed of the motor a. A stop may cut out the control of the generators by the governors below a certain speed. The idle generator may be maintained at a speed which is either above or below that of the motor. In the modification shown in Fig. 2, a tachometer dynamo m driven by the motor a, opposes either or both of the tachometer dynamos h1, h2 driven by the generators cl, c2, thereby operating relays o1, o2 controlling the prime movers d1, d2.