PURPOSE: To reduce a variation of primary steam pressure, by a method wherein a control of supply quantity of lump coal is preceded by a control of combustion air quantity at the time of variation of the quantity of steam to be supplied to a load side.
CONSTITUTION: When a load is reduced suddenly and drastically, an output signal of a differential arithmetic unit 23 is reduced immediately, an output of a summing coefficient multiplier 24 is reduced, opening degree of a damper 15 is reduced by the signal immediately and combustion quantity is reduced rapidly. Thus, a rise of primary steam pressure is suppressed. On the contrary, when the load is increased, the opening of the damper 15 is enlarged immediately by the same action and decrease of primary steam pressure is prevented.
FUKUMOTO KATSUTOSHI
FUJITSUKA KOUJI
