电加热器匀速升降温过程中温度及其变化速率的多模型智能切换控制

Multi-model Intelligent Switching Control in Uniform Velocity Process of Electric Heater

在实验室电加热器匀速升降温控制中,由于温度的非线性和时变性,速率控制很难达到理想精度;温度上升或下降至稳态点附近时,在理想工艺曲线下,需同时对温度及其变化速率进行控制,出现了"单控制量-两被控量"的矛盾。针对上述问题,采用偏差累加方法在温度控制器基础上得到温度变化速率控制器,在匀速升温、降温过程中分别利用大幅、小幅对应传递函数构成偏差加权控制器,在控制过程中设计温度热惯性监测量实时监测控制器输出以进行温度及其变化速率的切换控制,在加热器装置上实验的结果表明,该方法提高了速率控制精度,很好地解决了温度及其变化速率控制的矛盾,使响应曲线与理想工艺曲线达到较大程度上的吻合。

During the uniform velocity process control of electric heater for lab use,the control precision is usually unsatisfied due to non-linearity and time-variability of temperature.When arriving near the steady state point,temperature and its velocity must be controlled simultaneously to achieve the perfect process curve,which leads to the contradiction of ＂ single control variable-two controlled variable ＂.Aimed at these problems,velocity error accumulated method was used to design the velocity controller based on the temperature controller,and model error weighted controller was made up of large range and small range model.Through the whole process,temperature inertia monitoring method was used to calculate the switching point of temperature control and its velocity control.The test results on laboratory electric heater device show that the controller satisfies high control precision.It solves the problem of control contradiction,and the response quality is highly improved.