SYSTEM FOR CONTROLLING SPEED OF ROTATION OF STEAM TURBINE Russian patent published in 1995 - IPC

FIELD: power engineering. SUBSTANCE: system has a hydromechanical actuating unit which includes slide valve, cutting off slide valve, servomotor interconnected through a pulse line and two-path electromechanical pulse unit. The first path includes governor, pickups, adder, the first electrohydraulic converter, and remote controlled valve. The second path includes governor, pickups, adder, the second electrohydraulic converter, and the second remote controlled valve. A switch is connected to the converters and remote controlled valves through oil pipe lines. The outlet nozzles of the converters are connected to inter-belt spaces of the switch and to the working spaces of a drive. Signals are added by the adders and the resulting signals are fed to the electromechanical drives which control gates of the converters. When the first remote controlled valve is open, the slide valve moves to the top stop, opens the port, feds power oil from the line to the inlet nozzles of the first converter and, in so manner, sets in operation the first path of the pulse unit of the system. Simultaneously, the slide valve overlaps the port and connects the face chamber with the drain through the openings, port and inlet nozzles of the second converter preventing returning the slide valve to the bottom stop when the second remote controlled valve is open. If the second remote controlled valve is open, closing of the first remote control valve causes shifting of the slide valve to the bottom stop under the action of a spring. In so doing, the port is closed and the second converter is connected to the power oil pipe line through the ports and the second remote controlled valve. Then the second path of the pulse unit of the system is set in operation. EFFECT: enhanced reliability. 1 dwg