Speed Control System Gas Turbine

Speed Control System Gas Turbine Points : Speed Control System Gas Turbine Power Plant During steady-state operation at a given Load the speed control system maintains rated turbine speed by regulating fuel flow to the turbine via the fuel control voltage (VCE) The speed control may. however, he overridden by the exhaust temperature control system, if the exhaust temperature exceeds the permitted limit for the existing load.
The load on the turbine is raised or lowered via the called for speed set point. When the set point is raised, fuel flow is increased, and load can be added at a rate that will maintain rated turbine speed. Thus the speed set point also serves as a load set point. The manual set point raise/lower handle, a speed set point meter, an actual turbine speed meter, and a VCE meter are located on the front of the control panel. The automatic function of the speed controlled system is accomplished as follows. Turbine speed is converted to a proportional industrial voltage via a frequency generator mounted on the turbine shaft. This frequency signal is converted to a proportional analog sped signal by circuitry in the speedtronic control panel.
The prevailing speed analog signal is compared with the called for speed set point and the rated speed set point. Any difference between the actual speed analog signal, the sum of the called Speed set point and the for speed set point 100% speed set point will result in a change of fuel flow to eliminate the difference there by regulating turbine spied.