GB415788A - Improvements in the regulation of gas turbines and the like - Google Patents

Abstract

415,788. Gas turbine plant. BRITISH THOMSON - HOUSTON CO., Ltd., Crown House, Aldwych, London, and FORSLING, B. E. G., Highcroft, Ashlawn Road, Rugby. March 3, 1933, No. 6535. [Class 110 (iii).] In a gas turbine plant, the quantity of air supplied by the compressor and the heat supply to the air are regulated in accordance with the turbine load, and the temperature of the gases fed to the turbine. Fig. 2 shows the application to a plant of the type described in Specification 413,697 in which a compressor 1 supplies air to a combustion chamber 2 from which the products of combustion pass to a turbine 4 driving a generator 5. The exhaust of the turbine 4 is used in a turbine 6 which drives the compressor 1, it being aided in this work by an electric motor 7. According to the invention, the aid given by the motor 7, which determines the output of the compressor 1, is regulated in accordance with the load on the turbine 4 by a speed governor 8, and the fuel supply valve 9 is regulated by a thermo-relay 10 at the inlet to the turbine. The arrangement may be reversed, that is, the governor 8 may regulate the fuel valve 9, and the thermo-relay 10 regulate the motor 7. In the modification shown in Fig. 4, a steam generator 11 with economizer 12 is arranged in the exhaust pipe of the turbine 6, and the steam is used partly in a turbine 13, which aids the turbine 6 in driving the compressor 1, and partly in a turbine 14 on the shaft of the power turbine 4. A speed governor 8 controls the admission valve 18 of the turbine 13 to regulate the output of the compressor, and a thermo-relay 10 controls the fuel valve 9. This arrangement may be reversed. A pressure-responsive valve 19 admits steam not required by the turbine 13 to the turbine 14, but the governor 8 may actuate this valve instead of the valve 18. In a modification, Fig. 5, fuel is burnt on a grate 26, and the thermo-relay 10, or the governor 8, regulates the temperature by operating dampers 24, 25. The exhaust from the turbine 6 passes through a heat-exchanger 21 in which the air is pre-heated. In a further modification, Fig. 6, in which only one turbine 4 is used, the compressor 1 being mounted on its shaft, the governor 8, or the thermo-relay 10 actuate a throttle valve 30 in the suction pipe of the compressor and also an admission valve 29 for the turbine. The air is preheated in a heatexchanger 21. The method of regulating may be applied to a plant working on a sub-atmospheric cycle wherein an exhauster takes the place of the compressor. Heat storage capacity may be provided in the gas stream in front of the turbine.