Patent ID: 7912676
Filing Date: 2011-03-22
Classification: G05B

Abstract:
1. A method for facilitating detection of abnormal operation of a process in a process plant, the method comprising: collecting first data sets for the process is producing a product by processing physical materials using one or more field devices communicatively coupled to one or more process controllers and while the device is in a first normal operating region, the first data sets generated from process variables of the process in the first normal operating region; generating a first regression model of the process in the first normal operating region using the first data sets, the first regression model a function of an independent process variable; determining a first range for the independent process variable in which the first regression model is valid; generating a process model to include the first regression model, the process model a function of the independent process variable; collecting second data sets for the process while the process is in a second normal operating region, the second data sets generated from process variables of the process in the second normal operating region; generating a second regression model of the process in the second operating region using the second data sets, the second regression model a function of the independent process variable; determining a second range for the independent process variable in which the second regression model is valid; revising the process model to include simultaneously the first regression model for the first range of the independent process variable and the second regression model for the second range of the independent process variable; and using the process model to detect and provide an indication of abnormal operation of the process, wherein abnormal operation is indicated based on one or more difference values, each difference value the difference between a measured value of a dependent process variable at a corresponding value of the independent process variable and a modeled value of the dependent process variable at the corresponding value of the independent process variable.