Study On AGC Control And Combustion Stability Control Of Gas Turbine

Gas turbine and gas combined steam cycle power generation technology has been developed greatly in recent years when our country introduced a large number ofgas turbine units from abroad. However, due to the technical barriers of foreign manufacturers to the gas turbine, the domestic gas power plant has many problems in the control of gas turbine. The operation of domestic gas power plant is still in the stage of continuous exploration and research.Different from the coal fired units, the maximum power of the gas turbine has much relationship with the environmental temperature and atmospheric pressure. The unit has been locked in the low load stage due to the exhaust temperature controller (OTC) action leading to the lifting load of the unit when the AGC test is not qualified.At high temperature in summer, the unit can not reach the rated load. These problems all affect the unit output. In addition, most of the gas turbine use low NOx lean burner. Lean burn technology is easy to be equivalent by the equivalent of the fuel and the change of the fuel composition. The shock of the combustion will have an impact on the thermal insulation of the combustion. SIEMENS F type gas turbine has no other measures to control the combustion stability.except the main protection of gas turbine trip. It is necessary to study the stability of combustionThis paper sets up from the design idea of the OTC controller, and optimizes the exhaust setting value of the inner limit boiler, eliminatting the error limit of OTC controller to the load. According to the given curve from the manufacturer, we find out the factors that limit the load of the unit.The dynamic upper bound of the load of the unit is calculated by fitting the field curve. The formula is used to AGC control by the grid,solving the problem which the AGC command is greater than the maximum output of the generating unit, providing reference knowledge for the same type of units.In this paper, a set of decision rules for the combustion stability of a gas turbine is summarized to analyze the Fu Liye transformation of the gas turbine acceleration signal.The rule can make a judgment in advance before combustion deterioration,through large analysis of several times of combustion instability. The combustion stability control strategy is put forward based on the characteristics of SIEMENS F type gas turbine.