Optimization Research And Application Of 350MW Unit Control System

The coordinated control system of thermal power units is the link between power grid and unit generating units,which is related to the safety,stability,economy and active power regulation level of power grid.Boiler combustion control system is one of the subsystems with the most influence factors and the most difficult control in power plant system.Due to load fluctuation or coal quality change,the problems of parameter overrun and the difficulty of lasting combustion optimization experiment results are the important technical defects of traditional control strategy.Based on the engineering practice in the control field of 350 MW Subcritical Units in Huaneng Nantong Power Plant,this paper improves and optimizes the coordinated control strategy of units according to the needs of units participating in the flexible control of deep peak shaving,effectively improves the automation level of coordinated control and combustion adjustment of subcritical thermal power units,and accumulates valuable experience for domestic units participating in deep peak shaving.The specific research contents and results are as follows:(1)The operation characteristics of 350 MW subcritical drum boiler unit are analyzed and studied.Through the object characteristic test,the characteristics of controlled object are mastered,and the reasonable control strategy is designed,which lays the foundation for the input of coordinated control system;(2)The flexibility test of combustion system of 350 MW subcritical drum boiler unit was carried out,the problems faced by deep peak shaving of the unit were identified,and the corresponding solutions were put forward;(3)The optimization test of combustion control system of 350 MW subcritical drum boiler unit was carried out.Under the premise of ensuring boiler safety and environmental protection,the requirement of deep peak shaving was met,and the boiler efficiency was improved as much as possible;(4)The characteristics of feed water control,main steam temperature control and reheat steam temperature control of 350 MW subcritical drum boiler unit under different working conditions are studied and analyzed.The control strategy of each subsystem is improved and the control parameters are optimized.The AGC mode is further studied under the condition of deep peak shaving.Combined with the relevant test results,a series of optimization adjustment methods are adopted,and the results are as follows It is an early unit participating in AGC dispatching of deep peak shaving in Jiangsu power grid,and the depth of deep peak shaving reaches 25% Pe;(5)The traditional primary frequency regulation control strategy is optimized and improved,which not only solves the common problems exposed in the process of drum boiler unit responding to primary frequency regulation,but also realizes the operation of primary frequency regulation function under deep peak shaving condition;(6)The RB function test under typical conditions is carried out,and the RB automatic regulation function of 320mw-350 mw units is successfully realized.