Integral control of a dependent variable in a system having at least two independent variables which influence the dependent variable

摘要

A method and apparatus for integral control of a dependent variable in a system having at least two independent variables which influence the dependent variable is disclosed. A difference signal indicative of the difference between the sensed dependent variable and a reference is integrated and provided to a hysteresis transfer function. The output of the transfer function is subtracted from the integrated difference signal and the resulting signal is used to control an independent variable which thereby influences the dependent variable only for small magnitude signal variations in the integrated signal. The integrated signal is used to control another independent variable for large magnitude signal variations in the integrated signal. The other independent variable is typically only capable of influencing the dependent variable for large magnitude signal variations.