330MW火电机组协调控制策略设计与优化

Design and Optimization of Coordinated Control Strategy in 330MW Power Unit

针对某330MW火电机组原协调控制无法正常投入的问题,进行DCS系统升级改造时,设计了全新的协调控制策略。对初次投入协调控制后,变负荷过程中负荷响应速度较慢、机组稳态时主汽压力波动较大的问题进行了详细分析。基于机组的动态特性和运行状况,从一次风压控制、锅炉主控、汽机主控等方面提出了优化方案,克服锅炉热惯性及迟滞性,并充分利用锅炉蓄热,提高机组变负荷能力。优化后机组投入了AGC控制,AGC试验结果表明:优化后的协调控制系统,在变负荷工况下,调节响应速度快、负荷动态偏差小;机组稳态时,主汽压力波动小,机组运行稳定。

In view of the problem that the original coordinated control of a 330MW thermal power unit cannot be put into normal operation,a new coordinated control strategy is designed when the DCS system is upgraded in this paper.After the coordinated control is put into operation for the first time,the problems of slow load response speed during load change process and large fluctuation of main steam pressure in the steady state of the unit are analyzed in detail.Based on the dynamic characteristics and operation conditions of the unit,to overcome the problems of large thermal inertia and hysteresis of the boiler,and make full use of the heat storage of the boiler to improve the load changing capacity of the unit,the optimization Schemes are carried out from the aspects of primary air pressure control,boiler main control,turbine main control,etc.AGC control is put into operation after optimization,the AGC test results show that the optimized coordinated control system has fast response speed and small load dynamic deviation under the condition of load change.In the steady state of the unit,the main steam pressure fluctuation is small and the unit operation is stable.