초록 ▼

A method is provided for controlling fuel flow to the combustor of a gas generator turbine during sudden changes in load or during a surge cycle of the process turbocompressor. Surge control is initiated by analog input signals emanating from various devices located throughout the compressor-process

A method is provided for controlling fuel flow to the combustor of a gas generator turbine during sudden changes in load or during a surge cycle of the process turbocompressor. Surge control is initiated by analog input signals emanating from various devices located throughout the compressor-process system. The fuel control system includes input signals from the gas turbine driver. These signals are acted upon by the fuel control system which transmits a signal to a fuel valve actuator that controls the valve that meters fuel to the combustor. In addition to this sequence of control communication, however, is a rate-of-change in the amount of the fuel provided. The rate of the increase of the amount of fuel is determined by current operating functions of the fuel control system. However, because of the characteristics of general load rejection and recovery, and the abrupt nature of surge, the rate of change in the flow rate of fuel is extremely high. This rapid increase of fuel to the combustor may lead to dangerous excursions in temperature, resulting in high temperatures in gas turbine elements. Consequently, a new function is added to the fuel control system's operation whereby improved regulation of the rate of increase of fuel is achieved. This new function receives a signal that either surge or a change in load has been detected. Next, a signal is transmitted to the fuel valve actuator, regulating fuel to the combustor, thus power to the power turbine, thereby preventing overspeeding. After that, the rate of change of the fuel valve is limited for a period of time. Once recovery has been accomplished, the change rate of the fuel valve is gradually returned to a normal operating setting.

대표청구항 ▼

[ We claim:] [1.] A method for preventing rotational speed excursions in a turbomachinery train comprising a gas turbine, a process turbocompressor, and a variable fuel flow having a normal rate of change of flow, the method comprising the steps of:(a) detecting surge within the process turbocompres

[ We claim:] [1.] A method for preventing rotational speed excursions in a turbomachinery train comprising a gas turbine, a process turbocompressor, and a variable fuel flow having a normal rate of change of flow, the method comprising the steps of:(a) detecting surge within the process turbocompressor; and(b) reducing the fuel flow to the gas turbine.