US1924377A - Regulator system - Google Patents

Description

Aug. 29, 1933. w. PONTOW 1,924,377

REGULATOR SYSTEM Filed Feb. 18. 1932 WITNESSES:

INVENTOR m Werner P017 fan ATTORNEY Patented Aug. 29, 1933 PATENT OFFICE 7 1,924,377 7 REGULATOR SYSTEM Werner Pontow, Berlin-Wilmersdorf, Germany,

assignor to Westinghouse Electric & Manufacturing Company, a corporation of Pennsylvania Application February 18, 1932, Serial No. 593,837, and in Germany February 27, 1931 Claims.

My invention relates to regulator systems and more-particularly to such systems employed for V controlling the speed of prime movers, such as steam turbines.

' It is general practice to control the speed of a steam turbine by means of a speed governor that is actuated .in accordance with the speed of the turbine, and 'to also provide a rapidly closing emergency throttle valve'to prevent dangerous over-speeding of the turbine. Should the turbine rapidly increase'its speed, as for example, when the load carried by the turbine is suddenly removed while 'the control valves are in a relatively wide open position, the emergency throttle valve of the turbine will completely shut oi the flow of steam supplied to the turbine, so that it becomes necessary to again start the turbine under manual control.

The speed governor mechanism, and also the emergency governor, usually employ a circulatlng. fluid, such as oil under pressure, that operates against pistons in pressure cylinders to open or close the valves. 1

In accordance with this'invention, a regulatzs-lng system is employed that controls the inlet valve by purely electrical means. A regulator system organized in accordance with this invention willnot completely shut off the flow of steam to the turbine when the load is suddenly removed therefrom, but will throttle the fiow of steam sufllciently to permit: the turbine to keep running idle-atsubstantially its normal speed.

Another feature of a regulator system organined inaccordance with this invention is the provision of means whereby, in the case above referral to, after the steam supply to the turbine has been reduced to a point where the turbine is running idle for a; short time, and load isagain applied to the turbine, the steamsupply control valve of the turbine is automatically opened at a relatively rapid rate to supply the necessary power to the turbine. When the supply of steam to the turbine corresponds substantially to that required to supply the turbine load, a further control of the steam supply isefiected through the governor mechanism. With this system, therefore, except for slight fluctuations, the speed of the turbine is kept continually. at itsnormal value. My invention will be better understood by reference? to the accompanying drawing, in which the single figure illustrates apparatus and circuits employed in a regulator system organized in accordance with my invention. Referring to the drawing, a steam turbine 1 is provided for driving an electric generator 2. A contact-making tachometer 3 is provided for controlling a steam supply valve 6 and operates the contact-making pointer 5 by means of the shaft 4 in accordance with variations in the speed of the turbine.

, The valve 6 is connected to a valve stem 7 and is actuated by a rack 8, carried on the valve stem and havinggear teeth engaging the teeth of a pinion 9 that is actuated by a differential gear mechanism 11 to control the valve position. The valve is normally biased to a closed position by means of a spring 12 that presses against a plate 13 on the end of the valve stem '7 and slides withinaguide 14. In order to prevent the valve 6 from being too violently slapped against its valve seat under the influence of the spring 12, a dashpot 15 is provided that is movable with the valve stem and within'which is slidably mounted a piston 16 that is carried by the rod 1'7 and suitable fixed against movement.

Movement of the valve 6 to control the speed of the turbine 1 is effected through the pinion 9, the shaft 18, a clutch 19 that is normally held in its closed or powertransmitting position by a spring 21, and a gear wheel 22, in accordance with the movement of the casing 23 of the differential mechanism 11. Planetary gears 24 are mounted on the interior of the casing 23 and revolve therewith. The planetary gears are engaged by gears 25 and 26 that are actuated, respectively, in accordance with the operation of electric motors 2'7 and 28. The gear'25 of the differential mechanism 11 is operatively conneeted to the motor 2'7, by means of a worm gear 29, and a worm 31, and the gear 26 of the differential mechanism is operatively connected to the motor 28 by means of a worm gear 32 and a worm 33'. 9a

The motors 2'7-and 28 are controlled by the contact-making pointer 5 of the tachometer 3 in accordance with variations in the speed of the turbine 1 from its desired-value. The motor 27 is energized from supplyconductors 34 and 35 to operate, in the one or in the other direction, upon the closure of the one, or the other of a pair of directional relays 36 and 3'1. The motor 2'7 comprises an armature winding 38 and a pair of differentially related field windings 105 39 and 41.

The directional relays 36 and 3'1 are energized from the supply conductors 42 and 43 upon engagement of the pointer 5 with the contact members 44 and 45, respectively, of the contact- I claim as-my invention:

1. In a regulator system, a prime mover, a regulating valve for controlling the supply of motive fluid to said prime mover, means for biasing said valve toward its closed position, means responsive to the speed of the prime mover for adjusting the position of the regulating valve, means actuated upon a predetermined increase in the speed of the prime mover above its desired value for disconnecting said second named means'from saidvalve thus permitting said biasing means to actuate said valve in a closing direction, and means actuated upon a predetermined closing of said valve for effecting a reconnection of said second named means to said valve.

2. In a regulator system, a prime mover, a regulating valve for controlling the supply of motive fluid to said prime mover, means for biasing said valve to its closed position, means responsive to the speed of the prime mover for adjusting the position of the. regulating valve, means actuated upon 'a predetermined increase in the speed of the prime mover above its desired value for disconnecting said' second named means from said valve thus permitting said biasing means to actuate said valve in a closing direction, means actuated upon a predetermined closing of said valve for efiecting a reconnection of said second named means to said valve, and means responsive to a predetermined decrease in the prime mover below its desired value for actuating said valve in an opening direction independently of said above named valve adjusting means.

3. In a regulator system, a prime mover, a

v regulating valve for controlling the supply of motive fluid to said prime mover, means for biasing said valve toward its closed position, a mechanism for operating said valve, an electroresponsive device for actuating said mechanism, means responsive to variations in the speed of the prime mover from its desired value for controlling the operation of said electro-responsive r device, and means actuated upon a predetermined increase in the speed of the prime mover above its desired value for disconnecting said mechanism from said valve, thus permitting said biasing means to actuate said valve in a closing direction.

4. In a regulator system, a prime mover, a regulating valve for controlling the supply of motive fluid to said prime mover, means for biasing said valve to its closed position, a mechanism for operating said valve, an electro-responsive device for actuating said mechanism, means responsive to variations in the speed of the prime mover from its desired value for controlling the operation of said electro-responsive device, means actuated upon a predetermined increase in the speed of the prime mover above its desired value fordisconnecting said mechanism from said valve, thus permitting said biasing means to actuate said valve in a closing direction, and means responsive to a predetermined decrease in the speed of the prime mover below its desired value for actuating said valve in an opening direction independently of said above named valve adjusting means.

5. In a regulator system, a prime mover, a regulating valve for controlling the supply of motive fluid 'to said prime mover, means for biasing said valve toward its closed position, a.

three element differential gear mechanism having one of said elements operatively connected to actuate said valve, electro-responsive means for actuating another element of said difierential gear mechanism, means responsive to variations in the speed of the prime mover from its desired value for controlling the operation of said electroresponsive means, means actuated upon a predetermined increase in the speed of the prime mover above its desired value for disconnecting said difierential gear mechanism from said valve, thus permitting said biasing means to actuate said valve in a closing direction, a second electroresponsive means operatively connected to the third element of said differential gear mechanism, and means responsive to a predetermined decrease in the speed of the prime mover below its desired value for controlling said second named electroresponsive means to efiect the operation of said valve in an opening direction independently of said valve adjusting means.

WERNER PONTOW.

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