Research And Application Of The Automatic Control System For Condensate Polishing Treatment In Ningxia Daba Power Plant

With the rapid development of the electronic and computer technology, China's power industry has improved quickly. Automatic control of power plant production that takes computer technology for centralization has attracted extensive attention; it has been playing an increasingly important role. Auxiliary power plant systems, such as ash handing system, make-up water treatment system, condensate polishing treatment system, wastewater treatment system, and coal handling system have also applied automatic prorram control technology.With constant improvement of power plant unit capacity and parameters, power plant'requirment to boilerfeed water is becoming stricter, so the imponance of condensate polishing treatment was drawed more and more attention by people.According to the problems of condensate polishing control loop in Huaneng dam Power Generation Co.Ltd,Through the comprison of traditional relay control,the control system based on PLC and the distributed control system(DCS),this paper proposed the transformation of control loop based on the third generation DCS product MACS (Meet-All-Customers'-Satisfaction) control system.So the automatic control of power plants condensate polishing treatment system based DCS platform has been achieved.The main works are as followers:①This paper makes an overall explanation of the significance of the condensate polishing treatment system in power plant, A detailed description was given of the condensate polishing treatment technological process,and this paper emphatically analyzed the working principle of the condensate polishing treatment control system and the PID control method.②The development and the application status of condensate polishing treatment control system was illustrated in this paper.And according to the improved requirement of condensate polishing treatment system, combined with equipments in the field, the whole project of condensate polishing treatment system was determined from economy, safety and reliability, practicality etc.③The hardware selection of the condensate polishing treatment control system was completed.It includes the design of MACS network, hardware structure and the collection of other hardware equipments.④The design of configuration software, operator station software, server software and control station software of MACS was completed. ⑤Based on the choice of the control system, hard selection, software program realization and operation debugging, the original system was reformed to MACS.From the actual operation situation, the condensate polishing treatment DCS system not only improves the quality of boiler feedwater, but also achieves each performance index, and it is convenient to mainten.Finally the author summarized the full paper and prospected the development of the condensate polishing treatment automatic control system, the author also points out that the condensate polishing treatment automatic control system need a longer time test and anti-interference technique should be paid more attention.