Research On Optimized Strategy Of Coordinate Control System Of600MW Power Unit

With the increase of grid capacity and load demand, more and more power-generating enterprises turn their focus to the construction and operation.Large generator units and supercritical units of600MW and above has been the main force unit of thermal power generation in China. The peak-valley gap is increasing greatly at present which requires power producer a timely response to the load variation to be effective on peak-shaving. For this purpose, coordinated control system (CCS) has been implemented to all large generator units to respond AGC (automatic generating control) instructions. For some features of supercritical units, it is stricter on the demand of power balance relationship for the supercritical once-through boiler has less heat storage which is different from traditional drum boiler during load changing; as well as direct-firing pulverizing system has been used in large generator units and the lagging of its response is bad for the quick response to the coordinate control of generator and boiler. The research of the control system of supercritical generator units would be helpful to increase the stability and economy of unit operation as well as the market competitiveness of power-generating enterprise.Firstly, the coordinate control system of generating unit has been introduced in this paper, and then comes different type and operation mode of the control system. From the comparison of once-through boiler supercritical unit and drum boiler subcritical unit, the analysis of the features of once-through boiler and the coordinate control strategy of supercritical units has been processed. At last, combined with the regulating test of No.4generating unit in Dingzhou plant to analyze the coordinate control strategy of this unit and optimize calorific value correction circuit and AGC control circuit with site test according to unit operation.