Abstract: A fuel control system for a premixed lean burn combustor in a combustion turbine engine, the combustor having at least two stages (P,S,T), the control system including; an air flow evaluation module having means utilising an iterative algorithm to derive an accurate value of total air flow to the combustor, the evaluation module further having means dividing the derived total air flow value into the proportions (Mp, Ms, Mt) required by the combustor stages (p,s, t) and outputting signals in parallel representing the air flow to respective combustor stages (p,s,t), and a control module associated with each stage (p,s,t) of the combustor and responsible for setting the fuel demand signal for the associated combustor stage (p,s,t), each control module being adapted to set the fuel demand signal with reference to an appropriate one of said output signals.

Abstract: A dual fuel gas generator (10) is provided with a steam injection system (48) having a bleed-off valve (66) and a steam metering valve which are controlled in concert by a controller (50) to supply steam to a steam manifold (22) for injection into the gas generator at rapidly variable rates independent of the steam supply rate from a boiler (42, FIG. 1). A proportion of the system can be reheated using a steam warm-up flow through the bleed-off valve (66). A further portion of the system can be purged and preheated using compressor delivery air to flow through a steam metering valve (80), a purge valve (74) and a drain valve (94). To control the degree of superheat at the steam manifold (22), water can be injected through a metering valve (90) and a vortex mixer (92), and to purge condensation from a gas fuel manifold (30, FIG. 7 ) of the gas generator, compressor delivery air can be allowed to flow through the manifold (30), a supply line (108) and a purge valve (112 to atmosphere.

Abstract: A duel fuel gas generator (10) is provided with a steam injection system (48) having a bleed-off valve (66) and a steam metering valve which are controlled in concert by a controller (50) to supply steam to a steam manifold (22) for injection into the gas generator at rapidly variable rates independent of the steam supply rate from a boiler (42, FIG. 1 ). A proportion of the system can be preheated using a steam warm-up flow through the bleed-off valve (66). A further portion of the system can be purged and preheated using compressor delivery air to flow through a steam metering valve (80), a purge valve (74) and a drain valve (94). To control the degree of superheat at the steam manifold (22), water can be injected through a metering valve (90) and a vortex mixer (92), and to purge condensation from a gas fuel manifold (30, FIG. 7 ) of the gas generator, compressor delivery air can be allowed to flow through the manifold (30), a supply line (108) and a purge valve (112) to atmosphere.

Abstract: Fuel flow is scheduled to a plurality of combustion stages by putting a plurality of engine fuel flow governors in parallel with each other and letting the governor which outputs the lowest fuel demand signal be the one which schedules the total fuel flow to the engine. Fuel flows to the plurality of combustion stages are then individually schedulled to achieve the lowest fuel flows consistent with predefined temperature limits for the corresponding stages of combustion.

Abstract: A duel fuel gas generator (10) is provided with a steam injection system (48) having a bleed-off valve (66) and a steam metering valve which are controlled in concert by a controller (50) to supply steam to a steam manifold (22) for injection into the gas generator at rapidly variable rates independent of the steam supply rate from a boiler (42, FIG. 1). A proportion of the system can be preheated using a steam warm-up flow through the bleed-off valve (66). A further portion of the system can be purged and preheated using compressor delivery air to flow through a steam metering valve (80), a purge valve (74) and a drain valve (94). To control the degree of superheat at the steam manifold (22), water can be injected through a metering valve (90) and a vortex mixer (92), and to purge condensation from a gas fuel manifold (30, FIG. 7) of the gas generator, compressor delivery air can be allowed to flow through the manifold (30 ), a supply line (108) and a purge valve (112) to atmosphere.