GB1348358A - Steam injection in gas turbine plant - Google Patents

Abstract

1348358 Gas turbine plant GENERAL ELECTRIC CO 27 April 1972 [12 May 1971] 19504/72 Heading F1G [Also in Divisions G1 and G3] The invention relates to a gas turbine plant in which means are provided to inject steam into the combustion equipment, there being means to control the flow of steam by means responsive to pressure in the compressor of the plant. In Fig.1 the flow of exhaust gases from the turbine 13 through line 38 is controlled by a device 37 having a flap member 37b pivotally movable by an actuator 37a such that the quantity of exhaust gas passing through line 38a to the steam generator 21 is controlled; the flows of exhaust gases through line 38a and by-pass line 39 rejoin in mixer 40 and discharge to the stack. Feed water is supplied to the steam generator 21 by pump 19 and the steam passes to separator 14 and thence through line 17 to the combustion section 12. The actuator 37a of the flap valve 37b is controlled by a control voltage generator 31 which comprises a pressure transducer 33 connected to compressor discharge pressure by line 36, the transducer supplying a signal E p to a comparator circuit 34 to which a reference signal E 0 is also supplied from a voltage source 32. The difference signal E E from the comparator is communicated to the actuator 37a whereby the amount of exhaust gas passing to the steam generator is varied. In Fig.2 the device 41 comprises a pressure transducer 42 and a comparator circuit 43 as in Fig.1 also a temperature sensor 44 disposed at the compressor inlet, the signal E T from the sensor passing to a function generator 46 the signal E 0 from which is passed to the comparator; the signal E E from the comparator is passed to the actuator 37a as before. The device 51 in Fig.3 comprises additionally a humidity sensor 54 at the compressor inlet, the signal E RH from which is passed to interpolation circuit 59. The signal E T from the temperature sensor is passed to function generator 56 also to function generator 57. The signal E' 0 from the generator 56 is passed to summation point 58, and the signal from generator 57 is passed to interpolation circuit 59, the resulting signal #E' 0 from the latter passing to the summation point 58. The resulting signal E 0 from the summation point is passed to the comparator circuit 53.