Stabilized Soil Mixing Plant Equipment Batching Control System Research And Development

In this thesis, the batching control system of stabilized soil factory-mixing equipment is designed and discussed. On the foundation of control technology now existed as well as domestic and foreign relevant information, we employ separated-integral PID (proportional, integral and derivative) algorithm in the system whose set point can be revised. And the algorithm is minutely discussed and designedIn this thesis, the weighting system of the stabilized soil factory-mixing equipment is detailedly analyzed, and a kind of new-type dust material measure structure is put forward .On the basis of technological requirement of the system, the small-scale DCS (Distributing Control System) with measuring, controlling and statistics functions is composed of several Siemens Company S7-200 series PLCs as slave, and one computer as master, which has higher performance-cost ratio.This thesis also introduces the design of communication protocol between PLC (Programmable Logic Controller) under free port mode and computer. Visual Basic 6.0 is adopted to program the HMI (Human-Machine-Interface).In final, the system is applied to an actual stabilized soil factory mixing equipment. The result shows that a very good control performance is achieved, and the system can maintain good weighing precision and stability in actual working conditions.