余热锅炉汽包水位控制是燃机废热利用项目中的难点，为此基于现有的串级PID控制方式和线性自抗扰的控制思想，提出一种新的水位控制方法。该方法以给水流量公式估计控制增益，以线性扩张观测器估计系统状态，并带有抗执行器饱和的措施。通过分析系统的稳定性条件，证明了该方法可使水位误差收敛至零。仿真结果表明，该方法调节时间短，抗干扰能力强，效果优于传统的串级PID控制，具有良好的应用前景。

Water level control in the heat recovery boiler drum is the difficulty of gas turbine waste heat utilization.Therefore,this paper proposes a control method based on linear auto disturbance rejection control.In this method,parameters of the controller are estimated by water flow formula,and system states are estimated by linear extended state observer.Furthermore,the measure of anti-saturation is implemented.By analyzing the stability condition of the water level system,it is proved that this method can make the water level error converge to zero.Simulation results show that this method has shorter settling time and stronger anti-interference ability,superior to traditional cascade PID control.

TM621