| 摘要 |
PURPOSE:To reduce the integral value of dead time greatly and to improve total heat efficiency by measuring and averaging load factors and performing predictor control. CONSTITUTION:A computing element 12 for an effective mean load factor calculates an effective load factor QL from a load factor QL and a correction coefficient K.Tc/T and averages the found load factor QL simply to calculate the effective mean load factor QL'. In this case, T is the integral value of dead time, T is a predetermined period, and K is a constant. Then, it is inputted to a trailing computing element 14 for the number of machines in operation in the form of, for example, 100% for all loads. The computing element 14 operates all of (n) units of cold and hot water machines when QL'=100% or n/2 units when QL'=50%. However, a decision on whether the number of machines in operation is varied or not at the present point depends upon the value of a temperature gradient M from an inclination computing element 13 and the exit temperature of the current cold and hot water machine. Thus, the predictor control is performed to decrease the integral value Tc of dead time and the total heat efficiency is improved. |
