Research On Data Reconciliation Of Thermal Power Plants

As an important support of China's energy industry,thermal power plays an significant role in the entire industry.The main steam flow is one of the key parameters reflecting the operation status of thermal power plant,which directly affects the accuracy of calculation results of coal consumption rate and heat rate,and condition monitoring of boiler,control optimization and the economic benefit analysis of the whole thermal power plants are inseparable from the main steam flow.However,in the thermal measurement of thermal power plants,there are a lot of problems in the measurement of main steam flow,because the throttle loss caused by direct measurement method can not be accepted by large unit,and the accuracy of indirect measurement method can not be guaranteed,which have brought a lot of problems to a series of work based on data-driven in thermal power plants.Therefore,it has great significance to reconcile the main steam flow in thermal power plants.By using the redundancy in process measurements,data reconciliation can be used to eliminate and reduce the effect of measurement error,so it can enhance the reliability,the consistency and the integrality of the process data.In this paper,we reconcile the main steam flow in the steam turbine system of the thermal power plants by using data reconciliation technolgy.Firstly,starting from the relevant concepts and principles of data reconciliation,we apply linear steady-state data reconciliation to reconcile the results of flow measurement which contains error and estimate unmeasured variables in the cooling-water system,and compare the reconciled value and estimated value with the true value,the results show that the reconciled value is closer to true value than unreconciled value,and the estimated result also has a certain accuracy.Secondly,we apply data reconciliation to reconcile the measured main steam flow in the the steam turbine system of a power plant 1000 MW Ultra-Supercritical 13 unit,and analyze the reconciled result by the relationship between the main steam flow and unit load as well as design value,the results show that the reconciled main steam flow is closer to true value than the unreconciled value.At the same time,we estimate the unmeasured flow variables in the steam turbine system,and analyze the estimated results by comparing with design value,the results show that the estimated flow also has a certain accuracy.