A system and method for instantaneous fuel optimization of thermal power units with double-inlet and double-outlet coal mills

Abstract

The invention discloses a double-in and double-out coal mill thermal power generating unit instantaneous fuel optimization system and method. The system comprises a fuel control unit, an instantaneous fuel optimization calculation and conversion unit, a normal operation working condition coal quantity closed loop measuring unit and an abrasive belt load stopping memory storage unit, wherein the fuel control unit is used for receiving a control instruction sent by a boiler and an acceleration signal of a variable load, calculating a control signal of a coal mill capacity air door, and sending a result to the instantaneous fuel optimization calculation and conversion unit; the instantaneous fuel optimization calculation and conversion unit is used for judging a conversion condition through operation states of a corresponding coal mill and coal feeder, and transmitting a result to the fuel control unit; the normal operation working condition coal quantity closed loop measuring unit is used for forming an instantaneous fuel quantity correction factor through a theoretical coal quantity which is linearly determined by the capacity air door and a coal feeder instantaneous coal quantity and according to a difference between the quantities, and sending a result to the instantaneous fuel optimization calculation and conversion unit; and the abrasive belt load stopping memory storage unit is used for receiving a result of the normal operation working condition coal quantity closed loop measuring unit.

Description

technical field [0001] The invention relates to the technical field of coal mills, in particular to a system and method for instantaneous fuel optimization of thermal power units with double-inlet and double-outlet coal mills. Background technique [0002] The double-inlet and double-outlet coal mill is a new type of pulverizing equipment developed on the basis of the single-inlet and single-outlet coal mill. It overcomes the shortcomings of the single-inlet and single-outlet coal mill that cannot be used for direct blowing because of its single function. It integrates functions such as drying, grinding, powder selection, and powder delivery. It has simple system layout, high degree of automation, and adaptability to coal types. Wide range of properties, high fineness of pulverized coal, simple maintenance and operation, etc., meet the development requirements of modern large-scale power plants. [0003] The emergence of double-inlet and double-outlet coal mills has ended t...

AI Technical Summary

Problems solved by technology

However, because the raw coal delivered by the coal feeder first enters the coal mill cylinder for grinding and level storage, and then is carried into the furnace by the primary air for combustion instead of all entering the furnace, which makes it difficult to measure or The instantaneous coal amount measured by weighing cannot really represent the amount of fuel that actually enters the furnace, and the unit coordination control system cannot accurately control the amount of fuel, resulting in unstable main steam pressure control under variable load and steady-state operating conditions of the unit

Especially in supercritical and ultra-supercritical once-through furnaces equipped with double-inlet and double-outlet coal mills, it will have a serious impact on the water-coal ratio control and main steam temperature control, which will lead to unit pressure, main steam Defects such as poor regulation of steam temperature and steam superheat degree at separator inlet

[0005] At present, there is still no effective measurement and calculation method for the instantaneous fuel of thermal power units equipped with double-inlet and double-outlet coal mills

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