GB833097A - Improvements in or relating to starting arrangements for gas turbine power plants - Google Patents

Abstract

833,097. Gas turbine plant. SVENSKA TURBIN AKTIEBOLAGET LJUNGSTROM. Nov. 7, 1957, No. 34740/57. Class 110 (3). A starting arrangement for a gas turbine power plant having a low-pressure compressor and a high-pressure compressor coupled in series comprises a starting compressor, which operates during starting only and which is preferably a jet-type compressor, located in the air ducting between the compressors and in front (in relation to the direction of flow) of the high-pressure compressor for supplying air under pressure to the high-pressure compressor for starting the gas turbine power plant and for simultaneously drawing air through the lowpressure compressor. A low-pressure compressor 1 discharges through an intercooler 2 to a high-pressure compressor 4 which supplies air to a combustion chamber 5 feeding a turbine 7 driving the air compressor 4, a turbine 8 driving the compressor 1 and a turbine 9 driving an electrical alternator 10. The duct 3 is divided at the inlet to the compressor 4 into two branch ducts 11, 12. The duct 11, which leads to the intake of the compressor 4 directly, has a louvre-like shut-off device 13 which automatically closes when the pressure in front of the compressor 4 rises to a predetermined value and opens when the pressure is reduced below this value. The branch duct 12 directs air to a starting compressor or blower 14 disposed in front of (in the direction of flow) the compressor 4 and spaced therefrom so as not to obstruct air inflow from the duct 11. The starting compressor may be a motor-driven compressor or, as shown, a jet compressor supplied with air under pressure from a vessel 15. The shut-off device may be a swivelling flap or throttling member which is automatically controlled by a servo-motor.