Development Of The Contral System For Condensate Fine Treatment System Of Power Plant Based On PLC

The fine treatment of condensate plays a vital role in steam-water treatment of thermal power plant.The process is to retreat the steam condensation water after working and deliver back to the feed water system of boiler.The bad quality steamwater will cause serious question,such as causing boiler exchanger and turbine blade scaling or damage.So the reliability and efficiency of condensate fine treatment have significant effect on security and environmental protection of power plant,which has become the key research object at home and abroad.In this paper,a control system of condensate fine treating process is studied for the power plant.This paper analyzes the operation principle of condensate fine treatment system.According to the principle,control flow is established,which includes high-speed mixed bed unit,regeneration and wastewater treatment unit.For the nonlinearity and hysteresis problems in wastewater treatment control process,through combining with domestic and foreign relevant information about PID control principle and self-tuning method,PID self-tuning control scheme based on the relay feedback principle is finally constructed,and the dynamic mathematical model of acid-base neutralization process is established.After system simulation and error analysis,indicates that the design of the control scheme can overcome many unstable factors in the control system,which can effectively solve the problems of non-linearity and hysteresis.To develop the precision control system,the paper selects the hardware and software of the system,which takes Siemens S7 414 series PLC as the control core,STEP7 5.3 as software programming and INTOUCH 10.0 as aerial surveillance software collocation.on this basis,Complete the fine treatment system process design,program writing and picture making,After configuration and debugging,the overall design of the control system is eventually finished.After the trial operation,the system can achieve predetermined linkage and logic control functions,which strengthens the security and reliability of the operation of the system and reduces the workload of the operation and operator.According to the on-site operation log,various parameters of system meet the design goal which proved that the hardware selection in the design,control scheme,software design and algorithm is correct.