CONTROLLER FOR GASIFIED POWER PLANT, GASIFIED POWER PLANT, AND CONTROL METHOD FOR GASIFIED POWER PLANT

摘要

An IGCC plant includes a coal gasifier that gasifies coal by using an oxidizer, a gas turbine that is driven by combustion gas generated by combustion of fuel gas obtained by purifying gas generated by the coal gasifier in gas clean-up equipment, and an oxidizer supply path for supplying air extracted from an air compressor of the gas turbine or oxygen separated from the air as an oxidizer for the coal gasifier. A control unit (50) for the gasification power generation plant controls the amount of the oxidizer that is supplied to the coal gasifier to be less than or equal to a predetermined upper-limit value, while allowing deviation of an air ratio from a predetermined set value, the air ratio representing the ratio of the amount of air that is supplied to the coal gasifier relative to a theoretical amount of air for combustion of carbon, in accordance with variations in an operating-state quantity of the coal gasifier or variations in a load of the IGCC plant. Accordingly, the capacity of the oxidizer supplying equipment need not be increased in the IGCC plant, and it is possible to quickly stabilize control of the plant as a whole.