Methods and apparatus to predict process quality in a process control system

An apparatus to predict process quality in a process control system, comprising:

• a data receiver to receive process control information relating to a process at a first time including a first value associated with a first measured variable and a second value associated with a second measured variable;
• a processor to:
• determine if a variation based on the received process control information exceeds a first threshold;
• if the variation exceeds the first threshold, calculate a first contribution value based on a contribution of the first measured variable to the variation and a second contribution value based on a contribution of the second measured variable to the variation;
• determine at least one corrective action based on at least one of the first contribution value, the second contribution value, the first value, or the second value;
• calculate a predicted process quality based on the at least one corrective action at a time after the first time;
• calculate a first unexplained variation and a first explained variation associated with the first contribution value;
• and
• calculate a second unexplained variation and a second explained variation associated with the second contribution value;
• and
• a display manager to:
• display the first unexplained variation and the first explained variation in a chart by at least one of superimposing the first unexplained variation on the first explained variation or showing together the first unexplained variation with the first explained variation;
• and
• display the second unexplained variation and the second explained variation in the chart by at least one of superimposing the second unexplained variation on the second explained variation or showing together the second unexplained variation with the second explained variation.

A tangible machine-readable storage device excluding propagating signals comprising instructions that, when executed, cause a machine to at least:

• receive process control information relating to a process at a first time including a first value associated with a first measured variable and a second value associated with a second measured variable;
• determine if a variation based on the received process control information exceeds a threshold;
• if the variation exceeds the threshold, calculate a first contribution value based on a contribution of the first measured variable to the variation and a second contribution value based on a contribution of the second measured variable to the variation;
• determine at least one corrective action based on the first contribution value, the second contribution value, the first value, or the second value;
• and
• calculate a predicted process quality based on the at least one corrective action at a time after the first time;
• calculate a first unexplained variation and a first explained variation associated with the first contribution value;
• calculate a second unexplained variation and a second explained variation associated with the second contribution value;
• display the first unexplained variation and the first explained variation in a chart by at least one of superimposing the first unexplained variation on the first explained variation or showing together the first unexplained variation with the first explained variation;
• and
• display the second unexplained variation and the second explained variation in the chart by at least one of superimposing the second unexplained variation on the second explained variation or showing the second unexplained variation together with the second explained variation.

A method to predict process quality in a process control system, comprising:

• receiving process control information relating to a process at a first time including a first value associated with a first measured variable and a second value associated with a second measured variable;
• determining if a variation based on the received process control information exceeds a first threshold;
• if the variation exceeds the first threshold, calculating a first contribution value based on a contribution of the first measured variable to the variation and a second contribution value based on a contribution of the second measured variable to the variation;
• determining a first corrective action based on at least one of the first contribution value, the second contribution value, the first value, or the second value;
• calculating a predicted process quality based on the first corrective action at a time after the first time;
• calculating a third value associated with a calculated quality variable, the third value to be calculated based on at least one of the first measured variable or the second measured variable;
• calculating a third contribution value based on a contribution of the calculated quality variable to the variation;
• determining a second corrective action based on the third contribution value;
• determining if the first value exceeds a second threshold;
• determining if the second value exceeds a third threshold;
• determining if the third value exceeds a fourth threshold;
• if at least one of the first value, the second value, or the third value exceeds the respective one of the thresholds, indicating at least one of a process fault, a deviation of the first measured variable, a deviation of the second measured variable, a deviation of the quality variable, a process deviation, a duration of the fault, a cause of the process fault, or the variation of the process.

A method to predict process quality in a process control system, comprising:

• receiving process control information relating to a process at a first time including a first value associated with a first measured variable and a second value associated with a second measured variable;
• determining if a variation based on the received process control information exceeds a threshold;
• if the variation exceeds the threshold, calculating a first contribution value based on a contribution of the first measured variable to the variation and a second contribution value based on a contribution of the second measured variable to the variation;
• determining a first corrective action based on at least one of the first contribution value, the second contribution value, the first value, or the second value;
• calculating a predicted process quality based the first corrective action at a time after the first time;
• receiving process control information relating to the process at a second time including a third value associated with the first measured variable and a fourth value associated with the second measured variable;
• determining if a second variation associated with the process based on the received process control information at the second time exceeds the threshold;
• if the second variation exceeds the threshold, calculating a third contribution value based on a contribution of the first measured variable to the second variation at the second time and a fourth contribution value based on a contribution of the second measured variable to the second variation at the second time;
• determining a second corrective action based on the third contribution value or the fourth contribution value;
• and
• calculating the predicted process quality based on the second corrective action.

An apparatus to predict process quality in a process control system, comprising:

• a data receiver to receive process control information relating to a process at a first time including a first value associated with a first measured variable and a second value associated with a second measured variable;
• a processor to:
• determine if a variation based on the received process control information exceeds a first threshold;
• if the variation exceeds the first threshold, calculate a first contribution value based on a contribution of the first measured variable to the variation and a second contribution value based on a contribution of the second measured variable to the variation;
• determine a first corrective action based on at least one of the first contribution value, the second contribution value, the first value, or the second value;
• calculate a predicted process quality based on the first corrective action at a time after the first time;
• calculate a third value associated with a calculated quality variable, the third value to be calculated based on at least one of the first measured variable or the second measured variable;
• calculate a third contribution value based on a contribution of the calculated quality variable to the variation;
• determine a second corrective action based on the third contribution value;
• calculate the predicted process quality based on the second corrective action;
• determine if the first value exceeds a second threshold;
• determine if the second value exceeds a third threshold;
• determine if the third value exceeds a fourth threshold;
• and
• if at least one of the first value, the second value, or the third value exceeds the respective one of the thresholds, indicate at least one of a process fault, a deviation of the first measured variable, a deviation of the second measured variable, a deviation of the quality variable, a process deviation, a duration of the fault, a cause of the process fault, or the variation of the process.