Abstract: At present,the phenomenon of low operation efficiency and wasteful of energy widely exists in HVAC systems.The main reason is that HVAC systems have nonlinear,time-delay and time-variable characteristics,which lead to poor control performance with traditional control methods.It is one of the important ways to improve the control performance of HVAC control loops with the attemption to overcome the unfavorable influences of time-delay and time-variable characteristics.A self-tuning control algorithm with SMITH predictor is put forward in the paper.In the presented control infrastructure,an online identification method is used to estimate HVAC models with time-delay parameter.Then,based on the estimated parameters,the SMITH predictor is adopted to compensate for the time-delay characteristic.Furthermore,a PI controller within the predictor is introduced to improve the robust performance.Also,the control parameters of the control algorithm are updated in real time.Simulation results demonstrate that the proposed control method is superior to traditional control methods.

Key words: HVAC control system, SMITH predictor, self-tuning control, PI control

摘要： 目前暖通空调控制系统中普遍存在运行效率低下、能耗浪费严重的现象,主要原因在于暖通系统本身具有时变、时滞等非线性特性,使得传统的控制方法无法取得良好的控制性能。如何克服暖通空调系统时变和时滞特性所带来的不利影响,是提高暖通空调系统控制回路性能的重要途径之一。本文设计了一种基于SMITH预估的自校正控制算法,首先通过在线辨识包含时滞参数在内的暖通空调对象模型,进而采用SMITH预估器对时滞进行补偿,而SMITH预估器中的PI控制器则用于提高鲁棒性,并实现控制器参数的实时更新。仿真结果表明该算法性能要优于传统的控制方法。

关键词: 暖通空调控制系统, SMITH预估器, 自校正控制, PI控制