MODE TRANSITION METHOD FOR MULTISTAGE COMBUSTOR AND FUEL CONTROL DEVICE FOR GAS TURBINE

摘要

PROBLEM TO BE SOLVED: To control the rate of fuel to be supplied into a pilot region by detecting the filled condition of the fuel in a main combustor fuel line. SOLUTION: A fuel control system for a gas turbine having a multistage combustor consists of a device and a method for operating the combustor in transition between two modes of pilot operation and multistage operation. A fuel control has a switch incorporated in a hysteresis for determining a transition point between operation modes. The combustor is switched from the pilot operation into the multistage operation at a thrust level greater than a thrust level in which the combustor is switched from the pilot operation into the multistage operation. In transition between the operation modes, a change of a fuel flow is restricted by a plurality of limited rates to prevent the fuel spike and blow-off of the combustor. During starting an engine, a fuel line to the main combustor is prefilled to give responsiveness in transition from the pilot operation into the multistage operation. COPYRIGHT: (C)2005,JPO&NCIPI