Smith预估模糊PID控制算法及其在粉末定量称重中的应用

针对上海科源电子科技有限公司研发的定量称重系统（由高精度抖粉装置与万分之一天平组成），在工作中因粉末密度、粉末流动性、颗粒大小、湿度、天平延时等因素造成的非线性和滞后等问题，采用Smith预估模糊PID控制器优化控制方法。首先通过理论分析，得出系统的传递函数，再构建Smith预估的模糊PID控制器，以适应系统的非线性、滞后等特性，最后将此算法代入MATLAB进行仿真并于实际系统中进行1 g定量抖粉实验。Smith预估模糊PID控制算法和传统PID算法的标准差分别为0.0020和0.0042，表明Smith预估模糊PID控制算法在实际环境中稳定性更好，能有效减小系统的称重误差。

Smith predictive fuzzy PID control algorithm and its application in powder quantitative weighing

Aiming at the quantitative weighing system developed by Shanghai Cohere Electronic Technology Co., Ltd. (consisting of a high-precision powder shaking device and a 1/10000 balance), which has nonlinearity and time delay problems due to factors such as powder density, powder fluidity, particle size, humidity, and balance delay during operation, the Smith predictive fuzzy PID controller is used to optimize the control method. Firstly, based on theoretical analysis, the transfer function of the system is obtained, and then a Smith predictive fuzzy PID controller is constructed to adapt to the nonlinearity, time delay, and other characteristics of the system. Finally, this algorithm is substituted into MATLAB to perform simulation, and a 1 g quantitative shaking experiment is carried out in the system. The standard deviation of the Smith predictive fuzzy PID control algorithm and the traditional PID algorithm is 0.0020 and 0.0042, respectively. In conclusion, the Smith predictive fuzzy PID control algorithm has better stability in practical environments and can effectively reduce the weighing error of the system.