应用专家PID实现某矿山半自磨机的控制

Application of Expert PID to Realize the Control of a Mine Semi-autogenous Mill

为了解决国内某矿山φ8.8 m×4.8 m型半自磨机的自动控制问题,采用专家PID控制系统进行了系统控制设计研究。结果表明:①影响半自磨机工作状况的因素较多,主要包括矿石性质、磨矿介质、给矿速率、磨矿浓度、衬板和格子板的状态等;物料充填状态可通过半自磨机的功率、轴压和磨音来判断,而料位状态控制可通过调节给矿量、给水量、加球量实现。②专家PID算法与传统PID的算法有明显的优势,其本质上是采用非线性设计手段,将专家经验引入控制策略的制定中,更适合复杂对象控制策略的实施,较好地克服常规PID对非线性系统适应性差、难以克服异常扰动以及对滞后时间常数难以确定等缺点。③在充分考虑了半自磨机工作特点的基础上,设计的专家PID控制系统可将半自磨机的轴压、功率稳定在设定值范围内,同时能根据半自磨机给矿量、给水量、顽石量、磨音等参数的综合分析,判断出半自磨机处于较为稳定的工作状态。

In order to solve the automatic control problem ofφ8.8 m×4.8 m semi-autogenous mill in a domestic mine,the system control design research was carried out using the expert PID control system.The results showed that:①There are many factors affecting the condition of semi-autogenous mill,mainly including ore properties,grinding media,feeding rate,grinding concentration,state of liner and grid plate and so on.Material filling state can be judged from power of semi-autogenous,axial pressure and grinding sound,and the material level control can be realized by adjusting the amount of feeding,water supply and ball addition.②Compared with traditional PID algorithm,expert PID algorithm has distinct advantages.Expert PID essentially adopts nonlinear design method and introduces expert experience into the formulation of control strategy,which is more suitable for the implementation of complex object control strategy.Thus,it overcomes shortcomings of conventional PID better,such as poor adaptability to nonlinear system,and difficult to overcome abnormal disturbances and determine the lag time constant.③On the basis of fully considering the working characteristics of the semi-autogenous mill,the designed expert PID control system can stabilize the axial pressure and power of the semi-autogenous mill within the set value range.At the same time,it can judge whether the semi-autogenous mill is in the stable state,according to the comprehensive analysis of parameters,such as feeding,water supply,hard stone volume,and grinding sound of semi-autogenous mill.