超临界机组协调控制系统设计新方法及其工程应用

New Design Method of Coordinated Control System of Supercritical Pressure Power Unit and Its Application

超临界燃煤发电机组配置的直流锅炉,动态特性复杂。该文给出超临界机组协调受控对象的一种实用数学模型,采用观测器预估燃煤的热值,设计一种基于增量式函数观测的状态反馈+串级PID+智能控制(IC)+热值补偿(BTU)的综合型协调控制系统。采用数学方法描述了IC部分的具体内容,用状态空间法给出了整个控制系统的数学描述。通过数学分析,证明了系统稳定的充分条件,揭示了该综合型协调控制系统中串级PID调节器的作用。工程应用表明,在定压、滑压两种方式下变化负荷,其负荷速率可达12MW/min,证明了该控制系统的稳定鲁棒性。

The boiler of supercritical coal fired generating unit is once-through boiler, and its dynamic response is complex. This paper presented a practical mathematical model of coordinated control object of supercritical pressure unit, adopting observer to estimate coal heat value, and design a synthetic coordinated control system （CCS） with state feedback based on increment function observer （IFO）-KAx, PID, intelligence control （IC） and British thermal unit（BTU）（heat value compensator）. The details of the IC was described with mathematics method, and the full control system mathematics description was supplied with state space. The sufficient condition of system stabilization has been proved by mathematic analysis. The function of PID in this synthetic coordinated control system was shown. The project application shows that the load rate is 12 MW/min in constant and variable press mode. The system robustness is testified by practice and also provides an example improving response rate for supercritical press generating unit.