Method for online monitoring performance of steam turbine of coal-firing unit

Abstract

The invention provides a method for online monitoring performance of a steam turbine of a coal-firing unit. The method includes the following steps: step 1, according to boiler operation designing procedures, acquiring boiler structure parameters, and reading real-time data of operation condition measuring points of a steam-water system and a heat exchanger system at a given moment from a real-time database of a DCS (distributed control system); step 2, calculating specific enthalpy and density of a working medium on the basis of a working medium physical parameter library; step 3, according to a working medium side energy balance model, respectively calculating heat absorbed by the working medium in the steam-water system and the heat exchanger system to acquire total energy increment of the working medium; step 4, building a transmission function model between the total energy increment of the working medium and output power of the unit, and acquiring efficiency and heat consumption rate of the steam turbine through parameter recognition. The method can be used for online monitoring operation conditions of the steam turbine and providing technical support for coordination and optimization of the unit.

Description

technical field [0001] The invention relates to a real-time estimation technology of steam turbine performance in the field of thermal power generation control, in particular to an online monitoring method of steam turbine performance based on dynamic balance calculation of working medium side energy. Background technique [0002] The capacity of coal-fired thermal power units in my country accounts for about 75%, which is of great significance to the efficiency monitoring of thermal power units. The overall efficiency of coal-fired thermal power units mainly depends on boiler efficiency, steam turbine device efficiency, and pipeline efficiency. For subcritical units, the boiler efficiency is about 89-91%, and the pipeline efficiency can reach more than 98%, while the steam turbine system has a large cold-end loss, resulting in an efficiency of about 40%. It can be seen that the efficiency of the steam turbine system is the influence The short link of the overall energy con...

AI Technical Summary

Problems solved by technology

The calculation of heat absorption in this method adopts an indirect calculation method, and the accuracy is difficult to guarantee. In addition, more hardware equipment needs to be installed on site, which requires a large one-time investment and high modification costs.

Images