Method and computer program product for improved transient response

• US 6,828,765 B1
• Filed: 04/26/2002
• Issued: 12/07/2004
• Est. Priority Date: 12/29/2000
• Status: Expired due to Term

• Current Assignee: Volterra Semiconductor Corporation (Analog Devices, Inc.)
• Original Assignee: Volterra Semiconductor Corporation (Analog Devices, Inc.)
• Inventors: Schultz, Aaron M., Lidsky, David B.
• Primary Examiner(s): HAN, YOUNGHUIE JESSICA
• Application Number:
  US10/133,115
• Time in Patent Office: 956 Days
• Field of Search: 323/282, 323/283, 323/284, 323/285, 323/286, 323/287, 327/159
• US Class Current: 323/284
• CPC Class Codes: H02M 3/157 with digital control

Abstract

A method and computer program product for use in a control system. The controller includes a first gain element configured to provide a first predetermined gain to an output error signal describing an error in the output of the control system; a compensator including a control loop including a storage element, the control loop receiving the output error signal, a second gain element configured to provide a second predetermined gain to the output of the control loop, and a detector configured to modify the contents of the storage element according to a predetermined adjustment value when a minimum predetermined excursion occurs in the output error signal; and a combiner configured to combine the outputs of the first and second gain elements to produce an output control signal for the control system.

Claims

1. A method for use in a controller of a control system, the controller having a control loop that includes a storage element, the method comprising:

receiving an output error signal describing an error in an output of the control system;

detecting when a minimum predetermined excursion occurs in the output error signal;

if the minimum predetermined excursion occurs in the output error signal, then

loading a predetermined adjustment value into the storage element, and

modifying an output of the storage element from a nominal value to the predetermined adjustment value; and

generating a control signal for the control system based on the output of the storage element.

2. The method of claim 1, wherein an output of the control loop is the output of the storage element, the method further comprising:

providing a first predetermined gain element to the output error signal;

providing a second predetermined gain element to the output of the control loop; and

combining outputs of the first and second gain elements to produce the output control signal.

3. The method of claim 2, further comprising:

providing a third predetermined gain element to the output error signal;

providing a predetermined delay element to the output of the control loop;

providing a fourth predetermined gain element to an output of the delay element; and

providing to the storage element a sum of outputs of the third and fourth gain elements.

4. The method of claim 3, wherein the sum of the third and fourth predetermined gain elements is one.

5. The method of claim 1, wherein loading a predetermined adjustment value comprises:

loading the storage element with a sum of the output of the control loop and the predetermined adjustment value.

6. The method of claim 1, wherein detecting comprises:

comparing the output error signal to two or more ranges, each range associated with a different predetermined preload value; and

supplying a predetermined preload value associated with a corresponding range when the output error signal is within that range.

7. A computer program product, tangibly stored on a computer-readable medium, for use with a controller of a control system, the controller having a control loop that includes a storage element, the product comprising instructions operable to cause a programmable processor to:

receive an output error signal describing an error in an output of the control system;

detect when a minimum predetermined excursion occurs in the output error signal;

if the minimum predetermined excursion occurs in the output error signal, then the product includes instructions to,

load a predetermined adjustment value into the storage element, and

modify an output of the storage element from a nominal value to the predetermined adjustment value; and

generate a control signal for the control system based on the output of the storage element.

8. The product of claim 7, wherein an output of the control loop is the output of the storage element, and wherein the product further comprises instructions operable to cause a programmable processor to:

provide a first predetermined gain element to the output error signal;

provide a second predetermined gain element to the output of the control loop; and

combine outputs of the first and second gain elements to produce the output control signal.

9. The product of claim 8, further comprising instructions operable to cause a programmable processor to:

provide a third predetermined gain element to the output error signal;

provide a predetermined delay element to the output of the control loop;

provide a fourth predetermined gain element to the output of the delay element; and

provide to the storage element a sum of outputs of the third and fourth gain elements.

10. The product of claim 9, wherein the sum of the third and fourth predetermined gain elements is one.

11. The product of claim 7, wherein the instructions operable to cause a programmable processor to detect comprise instructions operable to cause a programmable processor to:

compare the output error signal to two or more ranges, each range associated with a different predetermined preload value; and

supply a predetermined preload value associated with a corresponding range when the output error signal is within that range.

12. The product of claim 7, wherein the instructions operable to cause a programmable processor to load a predetermined adjustment value comprise instructions operable to cause a programmable processor to:

load the storage element with a sum of the output of the control loop and the predetermined adjustment value.