JPS57182019A - Combustion controller for boiler - Google Patents

Abstract

PURPOSE:To prevent generation of black smoke and formation of clinker, by providing a gain and integral timing generator to be energized in accordance with the change of the steam flow and combustion air flow, and by controlling a feed-coal controller and a combustion air-flow, controller at the time when a loading is increased and decreased, in response to the output from a timing generator. CONSTITUTION:When the loading to a boiler is increased, during operation, the output from a steam flow detector 02 is increased, and a positive deviation signal is outputted from an adder-subtractor 29 which receives the output from a combustion air-flow detector 09. A proportional integrator 30 calculates the predetermined output signal using a gain and integral timing selected by a gain and integral timing generator 34 in accordance with the deviation signal, and controls a combustion air flow controller 11. At this time, the pressure of steam is decreased, so that the output from a proportional integrator 25 is increased by a deviation signal from an adder-subtractor 22 which receives the outputs from a steam pressure detector 01 and a setter 21. With such an arrangement, a coal-feed controller 05 is controlled to the coal-feed increasing direction through a low signal selector 28, an adder-subtractor 31 and a proportional integrator 32.