一种基于改进形状分析的黏滞特性检测方法研究

Study on Stiction Characteristics Detection Methods With an Improved Shaped Analysis

调节阀黏滞特性是导致工业过程中控制回路振荡的主要原因之一。现有的调节阀黏滞特性检测方法大多都以特定假设为前提,只适用于特定的范围。针对面积峰值法仅适用于自衡对象的限制,提出了一种改进的形状分析法,基于自衡对象和积分对象回路输出形状的差异,对振荡回路偏差信号的二阶导数信号与原信号的较大差异性进行区分,从而进行黏滞特性检测。该方法克服了面积峰值法只适用于特定范围的局限性,通过仿真研究验证了该方法的有效性。

Valve stiction is one of the main causes for control loop oscillation in industrial processes. Most of the existing control valve stiction detection methods are based on specific assumptions. It is only applicable for a specific scope. Aiming at the limitation that area peak method is only applicable to self-regulating object, an improved shaped analysis method is presented. Based on shape difference of loop output for self-regulating object and integral object, the larger difference for second derivative signal of vibration loop error and original signal are distinguished to conduct stiction characteristics detection. The method overcomes the limitation of area peak method only applicable to a particular range. The simulation experiment validates effectiveness and reliability of proposed method.