The Hoist Speed Control System Based On Predictive Control Theory And Dynamic Torque Switch

The metallurgical industry is a basic industry, and the development of many other industrialsare closely related to it. This is an utmost important to realize the purpose that to improve theefficiency of metallurgical processes, to ensure the reliability and security of the metallurgicalprocess.Hoist speed control system, in particular, which is used in blast furnace hoisting speedcontrol system is the core of the feeding process in the metallurgical process, whether thefeeding speed is timely or appropriate, to some extent, determines the efficiency of thesmelting process. The majority of domestic hoist speed control mode is a simple and directspeed current (torque) of double closed loop control mode, due to the limitations of this controlmethod, as well as for the safety of the hoist wire rope,in order to prevent material vehiclevibration and "hanging" incident, which will seriously affect the production, so this system isrequired to transform.In this paper, the principle of the existing DC winch systems are made comparison andanalysis, to find their advantages and disadvantages, and on the basis of those, a moreoptimized control method-the hoist control system based on switching on torque is proposed.For asynchronous motors, using the armature dual-response theory armature current can bebroken down into the excitation current component and the torque current component. Similarto the control of DC machine, we can control this system, which has developed to the spacevector control method of asynchronous motor and gained the same even better speedperformance. New control method applied to DC winch system can be also applied to the spacevector control of AC induction motor AC hoist system. On this basis, considering the actualsituation that the materials，iron or coal, that needs to be transporting is in accordance with thesystem. Due to their difference in weight, in order to make the system more stable requires thesystem to forecast and control the difference，so that the system will have better performance.Finally, this paper proposes the hoist speed control system based on predictive control andtorque followed. This is an optimistic system with PLC and digital speed control devices.System is up to safe and reliable operation and high efficiency. Experiments and practical usesmeet the feature of fast, safe, reliable, and simple maintenance requirements.