| 摘要 |
<P>PROBLEM TO BE SOLVED: To control a combustion state to come into an optimum one corresponding to the state of a load in a multi-drum boiler which performs the control of increasing and decreasing the number of control target boiler units in which the number of control target boiler units subjected to operation control is changed. <P>SOLUTION: The multi-drum boiler; computes an operation rate which is a ratio of a present combustion amount to a possible amount of the combustion in the whole of boiler units under the control; performs the operation to decrease the number of control target boiler units when its operation rate continues longer than a time (a) to decrease the number of control target boiler units in a state that the operation rate is lower than a set value set to a value lower than half; and performs the operation to increase the number of control target boiler units when the operation rate continues longer than a time (b) to increase the number of control target boiler units in a state that the operation rate is higher a set value set to a value higher than half. The multi-drum boiler: clocks a time (c) required to change the number of control target boiler units that is a time until it performs the operation to increase the number of control target boiler units or the operation to decrease the number of control target boiler units next since it has performed the operation to decrease the number of control target boiler units or the operation to increase the number of control units, and changes the time (a) to decrease the number of control target boiler units or the time (b) to increase the number of control target boiler units in case that the time (c) required to change the number of control target boiler units is less than a criterion value. <P>COPYRIGHT: (C)2013,JPO&INPIT |
