Redundancy Design And Research In The Coal Belt Conveying Control System

Currently, the Siemens PLC automation controller has been applied broadly in coal conveying-belt control system. First, it can support reliable real-time data for thermal power plant management making decision and it also displays in real-time the coal consuming of generator under certain load. Second, it has high reliability, strong practicality, strong anti-jamming ability and flex extension ability. Therefore, its application would greatly reduce the labor intensity of workers, at the same time, it is convenient for function extending and equipment upgrading. The application of redundant system would avoid system stopping or bigger problems due to system maintenance,system error or incorrect operation, so although the redundant system costs high, compared to the downtime losses, the redundant system is necessary. CPU and network communication module with redundant configuration are generally chosen in PLC host system of coal conveying control system in power generators, and the Siemens S7-414 H which has the advanced SIMATIC S7 leads the development trend in redundancy control system.In this paper the application of Siemens S7-414 H redundancy control system is researched basing on the belt coal-conveying project of the generators.In this paper, Both hardware and software configuration of the system has been researched and designed, and finally a control scheme mainly with redundant PLC system was determined. In this scheme a distributed structure is used, and it has strong openness, high reliability, and easy extension. Control systems(including CPU, communication module, power supply, industrial control computer, etc.) apply redundant configuration, so it can greatly improve the reliability and stability. At the same time, the control system has friendly man-machine interface, and all the operations and tests are realized by the master computer. The whole process is monitored through WinCC monitoring screen, industrial control computer, keyboard, mouse, etc. This system can show the fault occurrence time, place, causes timely and accurately with interlocked protection function, also can save fault and operation records. In conclusion, this control system makes whole process run more stable, and also has the function of trouble shooting, operation monitoring, system debugging, alarm, and the protection of control system while it encounters accidents. Practical application proves that the coal belt-conveying redundancy control system is valuable in production.