1993 Volume 72 Issue 11 Pages 1092-1100
As an available method to precisely control the temperature of the adiabatic jacket of a calorimeter, a control system with programed manipulated variable is considered and the influence of the variable on the control characteristics is investigated. The programed manipulated variable is based on the known variation of the calorimeter temperature and is added to the manipulated variable of a follow-up control system. The control tests are mainly carried out by observing the variations of the temperature difference between the jacket and the calorimeter while the calorimeter is heated on various controlling or heating conditions.
Consequently, it is found that the programed manipulated variable can decrease the thermal lag of the jacket behind the calorimeter. The peculiar time lag of the heating system for the jacket can be also decreased if the programed manipulated variable precedes the actual temperature by the corresponding time to the equivalent dead time of the system. Since this method can minimize the heating power for the jacket, it provides the jacket with good follow-up characteristics to the calorimeter on temperature even using a simple heating system, not using such a complicated mechanism as the Nenken-style automatic calorimeter.