蒸汽发生器水位自适应滑模控制策略研究

Research on Adaptive Sliding Mode Control Strategy for Steam Generator Water Level

针对蒸汽发生器负荷扰动恶劣、运行工况多变及虚假水位效应导致的控制性能恶化问题,提出了一种蒸汽发生器水位自适应滑模控制策略。基于可移动边界理论建立了蒸汽发生器非线性动态模型,分离出蒸汽发生器水位、蒸汽流量和给水流量的对应关系,设计了一阶积分滑模面和滑模控制律,在此基础上考虑水位测量误差影响设计了水位自适应估计律,并根据李雅普诺夫理论验证系统稳定性。仿真测试表明:所设计的蒸汽发生器水位自适应滑模控制策略具有更优的性能,相较于传统PID和滑模控制策略其水位最大超调量和稳态控制偏差均最小,分别为1.3%和0.1%,能够适应工况变化和负荷扰动过程,提升了自适应滑模控制系统的变工况响应能力和抗扰动鲁棒性。

In response to the problems of poor control performance caused by severe load disturbances,variable operating conditions,and false water level effects in steam generators,a self-adaptive sliding mode control strategy for steam generator water level was proposed.Based on the theory of movable boundaries,a nonlinear dynamic model of the steam generator was established,and the corresponding re-lationship between the steam generator water level,steam flow rate,and feedwater flow rate was separa-ted.A first-order integral sliding mode surface and sliding mode control law were designed.On this ba-sis,considering the impact of water level measurement errors,a self-adaptive estimation law for water level was designed.The stability of the system was verified according to Lyapunov theory.Simulation tests show that the self-adaptive sliding mode control strategy designed for steam generator water level has better performance.Compared with the traditional PID and sliding mode control strategies,the maximum overshoot of water level and steady-state control deviation are the smallest,which are 1.3%and 0.1%respectively.It has the ability of adapting to changes in operating conditions and load disturbance process,improving the response ability of the self-adaptive sliding mode control system under variable operating conditions and anti-disturbance robustness.