钢坯加热炉具有多个温区,各温区存在着较强的耦合性,具有大惯性、大时滞及不确定性等特点,运行中还存在着负荷变化及燃气压力波动等扰动.由于建立准确数学模型很困难,使得一些解耦方法难以应用.针对加热炉的特点,提出了基于增益自适应的解耦方法,有效克服了模型偏差或系统参数摄动的影响.在解耦合的基础上,对各温区设计了温度串级双闭环交叉限幅比值控制.仿真结果表明:在系统参数大幅度摄动时,具有良好的解耦能力和优良的控制性能.
Billet heating furnace has different heat zones which boasting of strong coupling,big inertia and delay and uncertainty; and the change in load,the gas pressure fluctuation and the external disturbance jointly exist when the furnace operates,therefore,it is very difficult to establish accurate mathematical models,and these make some classical decoupling methods are difficult to be applied.Based on the reference models,a gain adaptive decoupling method was proposed to overcome the influence of model error and system parameter perturbation.On the basis of system decoupling,a temperature cascade control system with double-loop cross limiting ratio was designed for every temperature zone.The simulation results show that this control system has good decoupling ability and control performance when the parameters of temperature zones have greatly perturbation.