过热器温度的串级PID控制系统设计

Design of Cascade PID Control System for Temperature of Superheater

过热器的工质出口温度是电厂锅炉机组的重要参数指标之一,出口温度过高或是过低都会对汽轮机的运作造成影响,所以稳定的工质出口温度是整套机组正常经济运行的保证。针对某垃圾焚烧发电厂的二期扩建项目,设计了串级PID控制方案取代单回路的PID控制设计,直接控制过热器的出口温度,减少运行人员的工作量,提高自动化能力,加强了系统的抗扰动能力,使机组能够更好的稳定运行。通过MATLAB仿真,证明理论的可行性,同时在实际应用中取得理想的效果。

The outlet temperature of working medium of superheater is one of the important parameters of boilerunits in power sets. Too high or too low outlet temperature would affect the operation of the steam turbines. Therefore, the stable outlet temperature of working medium is the guarantee of normal operation of the whole boilerunit. Aiming at the second-phase expansion project of certain waste incineration power plant, a cascade PID control scheme is designed to replace the single-loop PID control, which directly control the outlet temperature of the superheater, reduces the workload of operating personnel, increases the automation level, strengthens the anti-disturbance capability, and enables the boilerunit to run more stably. The feasibility of the scheme is proved by MATLAB simulation. The ideal effect is obtained in practical application