초록 ▼

A means of controlling a process with a multiplicity of measurements dependent on one process parameter, so that only the most constraining of the measurements manipulates the process in such a way that the performance of each individual controller selected is equivalent to the performance if there

A means of controlling a process with a multiplicity of measurements dependent on one process parameter, so that only the most constraining of the measurements manipulates the process in such a way that the performance of each individual controller selected is equivalent to the performance if there were a single controller controlling only one measurement, the most constraining variable. The means of controlling also manipulates the process to prevent a measurement, that is within a process constraint limit, from excessively exceeding that process constraint limit when it is projected that it would do so without the corrective manipulation.

대표청구항 ▼

A method for controlling a process operating under supervision of a plurality of feedback control loops, said method comprising: (a) providing at least one constraint controller including a combination of operatively connected and interrelated override controllers, each of said override controllers

A method for controlling a process operating under supervision of a plurality of feedback control loops, said method comprising: (a) providing at least one constraint controller including a combination of operatively connected and interrelated override controllers, each of said override controllers including at least one individual controller, said override controllers combined in a preemptive constraint control system which system provides responsive regulation of interrelated process conditions attendant to said process being controlled; (b) selecting a group of variables to be monitored; (c) establishing operating parameters for said process being controlled based upon said group of variables, including (1) establishing a setpoint for each variable within said group of variables, said setpoint and its corresponding variable being controlled by a selected one of said individual controllers, (2) establishing a limit value for each of said variables within said group of variables, (3) establishing limit violation direction for each operating parameter, and (4) choosing a common process parameter to receive output from said individual controllers; (d) providing a plurality of monitoring means, said monitoring means being selectively connected with said override controllers and positioned to monitor said group of variables; (e) monitoring by selected ones of said monitoring means, each of said variables within said group of variables, and measuring at an instant in time each of said variables within said group, thus establishing a measured value for each of said variables; (f) storing each of said measured values; (g) then computing a pseudo-value of each of said variables within said group of variables, each of said pseudo-values corresponding to a respective one of said measured values which said pseudo-value and said measured value form a corresponding pair of values; (h) storing each of said pseudo-values; (i) then selecting one of said measured values and comparing said selected measured value with its corresponding pseudo-value, and repeating such comparison for each of said corresponding pairs of values; (j) establishing an array of adjustment values by utilizing sets of control values, each set consisting of one of said setpoints and said corresponding pair of values and computing for each of said control value sets a corresponding adjustment value, said adjustment value being used to bring said measured value of said control value set to a corresponding one of said setpoints; (k) selecting one of a plurality of said individual controllers by choosing a final adjustment value for said plurality of feedback control loops by selecting a maximum value from said adjustment values computed in step (j) if a positive adjustment value moves said process away from one of said limit values, otherwise, by selecting a minimum value from said adjustment values computed in step (j) if a negative adjustment value moves said process away from a selected one of said limit values, thereby leaving a number of non-selected individual controllers; (l) changing said common process parameter by said final adjustment value; and (m) repeating steps (e) through (l) in a continuous manner.