Abstract: A method of operating a combined-cycle gas and steam turbine power generating system on a single shaft 16 uses as a feedback to the speed control or governor a signal 22 representing the total power output of the generator less the total output of the steam turbine 12, which is then correlated with the error signal between the actual and reference speeds to alter the fuel flow to the gas turbine. By compensating the measured generator output by subtracting a value 24 representative of the steam turbine output so that the compensated signal 26 represents the contribution of only the gas turbine 10 to the generator output, a constant settable droop speed control system may be used in a single-shaft combined-cycle steam turbine and the gas turbine system to compensate for variable heating fuel value and/or changing combustion efficiency in dry low NO.sub.x combustion systems.

Abstract: A system and method for anticipating and controlling overspeed in a combined cycle turbine of the type having a gas turbine with a fuel flow control valve and a steam turbine with at least one steam control valve both disposed on a single shaft and having a heat recovery steam generator heated by said gas turbine and connected to supply steam to the steam control valve, the combined cycle turbine having a unified control system and driving a load. Below a preselected shaft speed the gas turbine fuel command signal controls power. Above the preselected shaft speed the steam turbine speed signal also controls power.

Abstract: A method for starting and loading a combined cycle turbine of the type having a gas turbine with a fuel flow control valve and a steam turbine with at least one steam control valve both disposed on a single shaft and having a heat recovery steam generator heated by said gas turbine and connected to supply steam to the steam control valve, the combined cycle turbine having a unified control system and driving a load and also having an auxiliary steam source connected to the steam control valve. The improved method comprises starting and cranking the combined unit by controlling steam from the auxiliary steam source with the steam control valve, initiating and controlling fuel flow to the gas turbine with the fuel flow control valve, initiating combustion, controlling acceleration of the combined unit with the steam control valve, transferring acceleration control of the combined unit to the gas turbine fuel flow control valve, and accelerating the combined unit to rated speed.

Abstract: An integrated boost compressor/gas turbine control system is provided in which a fuel gas boost compressor boosts the fuel gas pressure before supplying the fuel gas to the gas turbine control valves, namely the stop/speed ratio or pressure control valve and the gas control or volume valve, which in turn provide the fuel gas to the gas turbine. Pressure drops through these valves and hence boost power requirements are minimized by driving these valves to a fully open position under normal operating conditions, and using the valves in their normal control mode during other operating conditions such as start up and sudden load rejection. Thus, after startup operation, the system control is transitioned to the minimum system pressure drop of operation utilizing boost compressor flow control to control gas turbine fuel flow and hence gas turbine output power.

Abstract: A gas turbine control for ameliorating the adverse affects of cyclic load applications to both single-shaft and two-shaft gas turbines is disclosed. During cyclic load conditions, air flow is governed to control the output of the gas turbine while fuel flow is controlled to hold the firing or exhaust temperatures substantially constant.

Abstract: A gas turbine control for ameliorating the adverse affects of cyclic load applications to both single-shaft and two-shaft gas turbines is disclosed. During cyclic load conditions, air flow is governed to control the output of the gas turbine while fuel flow is controlled to hold the firing or exhaust temperatures substantially constant. Regular fuel flow governing during non-cyclic loading conditions is also provided.

Abstract: The invention relates to improved control systems for controllable pitch propellers of a twin screw vessel driven by a single prime mover operating at a predetermined rotational speed while the vessel is in the at sea mode, with provisions for maintaining the total load of said propellers upon the prime mover substantially constant under varying at sea conditions. A further element of the invention permits the transition of the control system to and from the maneuvering mode to the at sea mode under substantially smooth operating conditions of speed and power.