Patent ID: 6091887
Filing Date: 2000-07-18
Classification: G05B,H02P

Abstract:
A method of controlling an actual value of a physical parameter to a target value, comprising the steps of:a) repetitively measuring, at time intervals, the deviation or difference of the actual value from the target value, hereinafter referred to as control deviation, and the sign of said difference, hereinafter referred to as control sign;b) during or after each measurement, converting said control deviation into at least one electrical signal whose duration, referred to hereinafter as control deviation duration, is proportional to the absolute value of the control deviation, at least in a range near the target value and whose value is a function of the control sign;c) controlling a charge on an analog electrical memory element as a function of said at least one electrical signal, during the control deviation duration; andd) controlling said physical parameter as a function of said charge of said electrical memory element, thereby keeping the physical parameter within a predetermined desired range adjacent said target value.