水箱模型辨识及PID参数自整定技术研究

Study of water tank model identification and PID parameters self-tuning technique

为了达到对液位控制模型进行实时模型参数辨识,并实时计算出较为理想的PID参数对水箱进行实时控制的目的,采用最小二乘算法改进法及基于Ziegler-Nichols整定法的改良公式,进行水箱液位控制实验。得到对水箱液位进行实时控制的结果,其中超调量、控制时间均较为理想。结果证明此方法合理可行,具有对变化模型进行实时辨识的特点,结合动态辨识与基于模型的PID自整定法对非常规模型进行控制。

A method for identifying the model parameters and calculating the ideal PID parameters is presented to control the liquid level control system. An experiment of water tank liquid level controlling is made based on the improved least squares and improved formula based on Ziegler-Niehols tuning method to obtain ideal overshoot and controlling time. The ex- perimental results verify the feasibility of the method. With the characteristic of identifying the changing model in real-time, the method can control the unconventional model efficiently combined with dynamic identification and model-based PID param- eters auto-tuning method.