Auto-scaling controller and method of use therefor

In a controller, having a control input, for controlling a system to a desired output a method comprising the steps of:

• a) calculating a value for each of a plurality of control coefficients by fitting a polynomial function to a plurality of control transfer characteristic data;
• b) multiplying the values of the control coefficients by an first scaling value;
• c) multiplying the control input by a second scaling value;
• d) computing, over time, an output error signal based on a difference between the system output and the desired output;
• e) tuning the first and second scaling values using a descent-based optimization method;
• f) comparing the output error signal to an error threshold:
• and
• g) increasing the order of the polynomial function based on the comparison between the output error signal and the error threshold by adding at least one new polynomial term and a corresponding at least one new control coefficient.

A controller for controlling a system to a desired output, the system having a time dependent system output, the controller comprising:

• calculating means, operatively coupled to the controller, for calculating a value for each of a plurality of control coefficients by fitting a polynomial function to a plurality of control transfer characteristic data;
• first multiplying means operatively coupled to the calculating means for multiplying the values of the control coefficients by a scaling value;
• error computing means for computing an output error signal based on a difference between the system output and the desired output;
• and
• adjusting means, operatively coupled to the computing means and to the controller, for tuning the scaling value using a descent-based optimization method;
• comparison means, operatively coupled to the error computing means, for comparing the output error signal to an error threshold;
• and
• order increasing means, operatively coupled to the controller, for increasing an order of the polynomial function if the output error signal exceeds an error threshold by adding at least one new polynomial term and a corresponding at least one new control coefficient.

In a controller, having a plurality of control inputs and a plurality of control outputs, for controlling a system to a first desired output, the system having a time dependent system output a method for tuning the controller comprising the steps of:

• a) calculating a value for each of a plurality of first control coefficients by fitting a polynomial function to a plurality of first control transfer characteristic data;
• b) multiplying the values of the first control coefficients by a scaling value;
• c) computing a first output error signal based on a difference between the one of the plurality of system outputs and the first desired output;
• d) tuning the first scaling value using a descent-based optimization method;
• e) comparing the first output error signal to an error threshold;
• and
• f) increasing an order of the first polynomial function if the first output error signal exceeds the error threshold by adding at least one new polynomial term and a corresponding at least one new first control coefficient.

In a controller, having a plurality of control inputs, for controlling a system to a desired output, the system having a time dependent system output a method for tuning the controller comprising the steps of:

• a) multiplying each of a plurality of control inputs by a respective one of a like plurality of scaling values;
• b) computing an output error signal based on a difference between the system output and the desired output;
• c) tuning the plurality of scaling values using an optimization method to reduce the output error signal;
• d) comparing the output error signal to an error threshold;
• and
• e) increasing an order of the polynomial function in response to the comparison between the output error signal and the error threshold by adding at least one new polynomial term and a corresponding at least one new control coefficient.