Design And Research Of The Whole Process Water Supply Automatic Control System Of The Power Plant

At present,China ranks very high in the world in energy consumption ranking.Especially for thermal power generation,China has a very high degree of dependence.In the current situation,it is very unrealistic to complete the project of shortening the time from thermal power generation.Therefore,in the future,thermal power generation is still a very important power output energy structure.For the thermal power plant,the control of the boiler It is always a very important issue.Once the boiler can not be effectively controlled,it will lead to a serious accident in the operation of the entire power plant.Therefore,it is the basic task of every power plant to ensure the normal and safe operation of the boiler.For the boilers in the electric field,the full-scale water supply system for water supply is the object of study.The main reason is that once a problem occurs in the water supply system,Then the boiler will be a problem,in serious cases will threaten the safety of the entire power plant,so with the continuous development of current technology and the current unit is constantly increasing,the requirements for each power plant is also constantly increasing,the various power plants Efforts are being made to retrofit automatic water supply control systems in power plants so that they can efficiently supply water to boilers in power plants.Ensure that the power plant can run normally and safely.For the 300MW thermal power plant to be studied in this thesis,the whole water supply control system is researched,designed according to the corresponding requirements and the existing conditions,and then a set of automatic control according to the actual conditions of the power plant system.The thesis first briefly introduces the purpose and principle of the whole water supply control system and at the same time expounds the control of the water level in the drum.There are mainly three kinds of water supply control in the power plant,which are single impulse,double impulse and three impulse respectively Water control,a preliminary study of the three controls to determine the characteristics of different water control systems.In addition,in order to effectively control the water supply,the dynamic characteristics of the drum water level are studied correspondingly,mainly the dynamic characteristics of the steam flow,the feed water flow and the water level of the drum at the fuel flow.After preliminary analysis and research,preliminary design of water supply control system is carried out,including correction of feed water flow,steam flow and drum level signal.At the same time,single-impulse water supply control system and three-impulse water supply control system are designed and studied.It is found that when the two are controlled separately,once the load is too large or too small,the control range of the whole control system will be deviated,resulting in poor control effect.Therefore,in order to solve this problem,System and three impulse water supply control system was designed to come up with a set of automatic water supply control system.The mathematic model of automatic water supply control system was established by Matlab simulation software and corresponding simulation research was carried out.At the same time,single-impulse water supply control system and three-impulse water supply control system were simulated.By comparing the simulation results,it was found that automatic water supply control The system effectively avoids the single impulse water supply control system inaccurate control when the load is too large and the three impulse water supply control system in the load is too small control ineffective shortcomings.Finally,a power plant in Jilin conducted a field test.Through the field test,we can verify that the automatic water supply control system designed in this thesis can effectively solve the problem of inaccurate control due to overloading and underload,Actual requirements.