Process controller having adjustable parameters

Abstract

Automatically generating a compensation factor for adjusting an operating parameter such that a measured carbon potential, dew point, or other controlled parameter matches the controller's set point value by inputting the measured parameter directly to the controller.

What is claimed is: 
     
         1 . A system comprising:
 a heat treatment furnace;   a controller coupled to the furnace for controlling one or more operating parameters thereof; and   a user human machine interface coupled to the controller;   wherein the controller includes a memory storing computer-executable instructions that, when executed, generate a compensation factor, the controller adjusting at least one of the one or more operating parameters based on the compensation factor, the computer-executable instructions comprising:   transforming a numerical equation for calculating the compensation factor into a homogeneous form;   initializing the transformed equation based on a set of initial values;   iteratively solving the transformed equation to determine a value of the compensation factor that minimizes a difference between a set point value of at least one of the operating parameters and a measured value of the at least one of the operating parameters.   
     
     
         2 . The system of  claim 1 , wherein the compensation factor is one or more of the following: CO factor, H2 factor, process factor, zone factor, gas factor, furnace factor, and calibration factor. 
     
     
         3 . The system of  claim 1 , wherein the at least one of the operating parameters is carbon potential. 
     
     
         4 . The system of  claim 1 , wherein the at least one of the operating parameters is dew point. 
     
     
         5 . The system of  claim 1 , the computer-executable instructions further comprising overwriting a previous value of the compensation factor with the determined value of the compensation factor upon receiving, via the user human machine interface, an indication that the determined value of the compensation factor is acceptable. 
     
     
         6 . The system of  claim 1 , the computer-executable instructions further comprising discarding the determined value of the compensation factor upon receiving, via the user human machine interface, an indication that the determined value of the compensation factor is unacceptable. 
     
     
         7 . A method of calibrating a gas carburizing furnace comprising:
 heating a shim in the furnace;   measuring a carbon potential of the shim;   providing the measured carbon potential to a controller, the controller coupled to the furnace for controlling one or more operating parameters of the furnace as a function of a carbon potential set point;   generating a compensation factor as a function of the measured carbon potential; and   adjusting at least one of the one or more operating parameters based on the compensation factor such that the measured carbon potential and the carbon potential set point are equal.   
     
     
         8 . The method of  claim 7 , further comprising providing an indication to the controller to store process data of the furnace after said heating the shim. 
     
     
         9 . The method of  claim 8 , further comprising verifying the stored process data matches the shim and the measured carbon potential thereof. 
     
     
         10 . The method of  claim 7 , further comprising overwriting a previous value of the compensation factor with the generated compensation factor upon receiving, via a user human machine interface, an indication that the generated compensation factor is acceptable. 
     
     
         11 . The method of  claim 7 , further comprising discarding the generated compensation factor upon receiving, via a user human machine interface, an indication that the generated compensation factor is unacceptable. 
     
     
         12 . The method of  claim 7 , wherein said generating the compensation factor comprises:
 transforming a numerical equation for calculating the compensation factor into a homogeneous form;   initializing the transformed equation based on a set of initial values; and   iteratively solving the transformed equation to determine a value of the compensation factor that minimizes a difference between a set point value of at least one of the operating parameters and a measured value of the at least one of the operating parameters.   
     
     
         13 . A method of calibrating an endothermic gas generator comprising:
 measuring a dew point of gas within the generator;   providing the measured dew point to a controller, the controller coupled to the generator for controlling one or more operating parameters of the generator as a function of a dew point set point;   generating a compensation factor as a function of the measured dew point; and   adjusting at least one of the one or more operating parameters based on the compensation factor such that the measured dew point and the dew point set point are equal.   
     
     
         14 . The method of  claim 14 , further comprising verifying the stored process data matches the measured dew point. 
     
     
         15 . The method of  claim 13 , further comprising overwriting a previous value of the compensation factor with the generated compensation factor upon receiving, via a user human machine interface, an indication that the generated compensation factor is acceptable. 
     
     
         16 . The method of  claim 13 , further comprising discarding the generated compensation factor upon receiving, via a user human machine interface, an indication that the generated compensation factor is unacceptable. 
     
     
         17 . The method of  claim 13 , wherein said generating the compensation factor comprises:
 transforming a numerical equation for calculating the compensation factor into a homogeneous form;   initializing the transformed equation based on a set of initial values; and   iteratively solving the transformed equation to determine a value of the compensation factor that minimizes a difference between a set point value of at least one of the operating parameters and a measured value of the at least one of the operating parameters.