温室大棚温湿度跟踪切换最优控制器

温室大棚中的温湿度系统具有非线性、耦合关系强和滞后等特性,为了实现对温室的温湿度控制,建立了基于能量和质量平衡的温室大棚环境机理模型.针对温室大棚控制系统的非线性,对多个工作点系统进行线性化,得到了一组线性系统模型.基于切换思想,在不同工作点附近采用不同的系统模型参数;基于线性二次型性能指标,设计了温湿度跟踪切换最优控制器,并通过共同Lyapunov函数法验证了该切换系统的稳定性.仿真结果表明,设计的控制器可以很好地实现对温湿度目标值的跟踪控制.

Tracking switching optimal controller for temperature and humidity of greenhouse

The temperature and humidity system of greenhouse exhibits such characteristics as the nonlinearity, strong coupling relation and hysteresis. In order to realize the temperature and humidity control of greenhouse, an environment mechanism model for the greenhouse was established based on the balance of mass and energy. Aiming at the nonlinearity of control system of greenhouse, the linearity of system was performed for various operating points, and a group of linear system models were obtained. Based on the switching idea, different system model parameters were adopted around different operating points. Based on the linear quadratic performance index, a tracking switching optimal controller for temperature and humidity was designed. Through adopting the common Lyapunov function method, the stability of the proposed switching system was verified. The simulated results show that the designed controller can well realize the tracking control of temperature and humidity target values.