Method for coordinating and controlling quality change of coal in supercritical once-through boiler unit

Abstract

The invention discloses a method for coordinating and controlling quality change of coal in a supercritical once-through boiler unit. The method is used for building a boiler master control provided with balanced indirect energy, and comprises the following steps: quantifying coal quantity by load; quantifying primary air quantity by the coal quantity; confirming a dominant role of instructions of the boiler master control; jointly debugging the ratios of wind, water and coal to ensure that the superheat degree of the boiler meets the requirement; meanwhile, ensuring the control precision of the front pressure of the boiler unit to meet the requirements of a power grid for changing range and speed rate. The method mainly solves the problem that the unit runs fast while the boiler efficiency is low, and builds a novel static feedforward, a load dynamic feedfoward, a pressure dynamic feedforward, and dynamic corrections of the feedforwards based on quality change of coal; the linkage of wind, water and coal quickens the responsiveness of the boiler; the joint debugging of water and coal solves the problem of quality change of coal, realizes the decoupling of water and coal and the decoupling of main steam pressure and superheat degree; the linear real-time coefficient modifies various experience curves; and a main steam pressure regulator of the boiler master control is subjected to the variable parameter control.

Description

technical field [0001] The invention belongs to the technical field of coal power, and in particular relates to a coal quality change coordinated control method for an ultra-supercritical once-through boiler unit. Background technique [0002] At present, the quality of coal used for power generation in our country has changed greatly due to economic interests. Coal cannot be used according to the designed coal type. Bituminous coal and anthracite are mixed, and even to the point where coal is good. However, my country’s power grid’s assessment indicators for on-grid units are the response range and speed of the grid load and the ability of primary frequency regulation. Therefore, the coordinated control method of the unit mainly adopts the coordinated control based on boiler follow-up, that is, the boiler controls the pressure in front of the machine, and the steam turbine controls the unit through door adjustment. load. Now with the development of electric power technology...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the embodiments of the present invention is to provide a method for coordinated control of coal quality changes in ultra-supercritical once-through boiler units, which aims to solve the common problem of "fast machine and slow furnace" in current units, and the action of the boiler is much slower than the demand of the steam turbine; Especially now that coal-fired coal quality changes frequently and randomly, and its superheat is greatly affected. The problem of coal quality change has not been effectively and timely resolved, which has brought great safety hazards to power plants and power grids.

Images