US 5,347,446 A · Model predictive control apparatus

Abstract

A model predictive control apparatus constructed in consideration of limit conditions of the process and also suitable for a multi-input/output system and an input device suitable for such a control apparatus are disclosed. The model predictive control apparatus includes an transformation unit for transforming the cost function and the limit condition to a conditional expression only relating to the manipulated variable. A suitable cost function parameter adjustment unit in which robustness is taken into consideration is provided. Alternatively, by designation of a response time constant, a weight corresponding thereto is calculated or determined to carry out evaluation of stability margin. In addition, the input device is adapted to carry out, through a picture on screen, setting or alteration of a predictive model or control parameters, etc. to be inputted, thus to suitably conduct setting while confirming it on the screen.

Claims21

Dependent claims

A model predictive control apparatus comprising:

prediction means in which a model approximating a dynamic characteristic of a controlled system having a plurality of manipulated variables and controlled variables is used to determine a predictive equation of future values of the controlled variables;
and
arithmetic means adapted to transform limit conditions of a control condition to manipulated variables, and to calculate a manipulated variable to minimize an cost function in a quadratic form relating to a difference between a future reference value and a control variable, and a manipulated variable, set on the basis of said predictive equation while satisfying said limit conditions, thus to give the determined manipulated variable to said controlled system.

A model predictive control apparatus comprising:

prediction means in which a model approximating a dynamic characteristic of a controlled system is used to determine a predictive equation of future values of controlled variables;
arithmetic means for calculating or determining a manipulated variable to minimize an cost function in a quadratic form relating to a difference between a future reference value and a controlled variable, and a manipulated variable set on the basis of said predictive equation while satisfying a limit condition to give the manipulated variable thus calculated to said controlled system;
response time constant setting means for setting a response time constant indicating a rise time at which said controlled system should be operated;
weighting factor parameter calculation means for calculating a weighting factor including said response time constant at its exponential part, the value thereof increasing with lapse of time, and
cost function setting means for constructing a new cost function in which the calculated weighting coefficient is built in to set it as said cost function.

2 more elements

Dependencies are inferred from the claim text.

Model predictive control apparatus

Life of this patent

Model predictive control apparatus

Life of this patent

Abstract

Claims21