DYNAMIC LINEAR CONTROL METHODS AND APPARATUS FOR VARIABLE SPEED PUMP CONTROL

• US 20140005841A1
• Filed: 12/17/2012
• Published: 01/02/2014
• Est. Priority Date: 12/16/2011
• Status: Active Grant

• Current Assignee: Fluid Handling LLC (Xylem, Inc.)
• Original Assignee: Fluid Handling LLC (Xylem, Inc.)
• Inventors: CHENG, Andrew A., GU, James J., SCOTT, Graham A.
• Granted Patent: US 10,048,701 B2
• Time in Patent Office: Days
• US Class Current: 700/282
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• CPC Class Codes: G05D 7/0617 specially adapted for fluid materials
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

Apparatus, such as a pump controller, features a signal processor configured at least to: receive signaling containing information about a linear set point control curve based at least partly on an adaptive set point control curve related to fluid being pumped by a pump in a pumping system, and determine a control set point based at least partly on the signaling received. The signal processor may be configured to provide a control signal containing information to control the pump based on the control set point determined.

Claims

1. Apparatus comprising:

a signal processor configured at least to;

receive signaling containing information about a linear set point control curve based at least partly on an adaptive set point control curve related to fluid being pumped by a pump in a pumping system, and

determine a control set point based at least partly on the signaling received.

2. Apparatus according to claim 1, wherein the signal processor is configured to provide a control signal containing information to control the pump based at least partly on the control set point determined.

3. Apparatus according to claim 1, wherein the linear set point control curve is derived from the adaptive set point control curve with respect to system flow and pressure, including being derived from by the signal processor.

4. Apparatus according to claim 1, wherein the signal processor is configured to determine the linear set point control curve based at least partly on the following equation:

P*(t)=P₀Q*(t)/Q_max+b₀,

where P₀ is a constant pressure set point,

Q*(t) is a requested flow rate

Q_max is a maximum system flow rate,

Q_max is a maximum adaptive flow rate, and

b₀ is a pressure threshold.

5. Apparatus according to claim 4, wherein the signal processor is configured to determine a system flow rate as a summation of each individual zone flow rate, based as least partly on the following equation:

6. Apparatus according to claim 5, wherein the signal processor is configured to determine the system flow rate if zone temperature control parameters are used, based at least partly on the following equation:

7. Apparatus according to claim 1, wherein the signal processor is configured to determine a requested flow rate Q*(t) based at least partly on the following equation:

8. Apparatus according to claim 7, wherein the signal processor is configured to determine a pressure set point from the adaptive control curve directly based at least partly on the following equation:

P*(t)=(Q*(t)/C_v^a(t))².

9. Apparatus according to claim 1, wherein the signal processor is configured to determine the control set point based at least partly on a requested flow rate Q*(t) and derived from the adaptive set point control curve.

10. Apparatus according to claim 1, wherein the apparatus further comprises at least one memory including computer program code;

and the at least one memory and computer program code are configured to, with at least one processor, cause the apparatus at least to;

receive the signaling; and

determine the control set point based at least partly on the signaling received.

11. Apparatus according to claim 1, wherein the apparatus may include, or take the form of, a pump control or controller, including a PID control, having the signal processor.

21. A method according to claim 10, wherein the method comprises configuring the signal processor with at least one memory including computer program code;

and causing the signal processor and at least one memory at least to;

receive the signaling; and

determine the control set point based at least partly on the signaling received.

12. A method comprising:

receiving in a signal processor signaling containing information about a linear set point control curve based at least partly on an adaptive set point control curve related to fluid being pumped by a pump in a pumping system, and

determining in the signal processor a control set point based at least partly on the signaling received.

13. A method according to claim 12, wherein the method comprises providing with the signal processor a control signal containing information to control the pump based at least partly on the control set point determined.

14. A method according to claim 12, wherein the method comprises determining with the signal processor a requested flow rate Q* based at least partly on the signaling containing information about an intersection point between the linear set point control curve and the adaptive set point control curve, including the intersection point at a maximum adaptive flow rate, Q_max.

15. A method according to claim 12, wherein the method comprises determining with the signal processor the linear set point control curve based at least partly on the following equation:

P*(t)=P₀Q*(t)/Q_max+b₀,

where P₀ is a constant pressure set point,

Q*(t) is a requested flow rate

Q_max is a maximum system flow rate,

Q_max is a maximum adaptive flow rate, and

b₀ is a pressure threshold.

16. A method according to claim 15, wherein the method comprises determining with the signal processor a system flow rate as a summation of each individual zone flow rate, based as least partly on the following equation:

17. A method according to claim 16, wherein the method comprises determining with the signal processor the system flow rate if zone temperature control parameters are used, based at least partly on the following equation:

18. A method according to claim 12, wherein the method comprises determining with the signal processor a requested flow rate Q*(t) based at least partly on the following equation:

19. Apparatus according to claim 18, wherein the signal processor is configured to determine a pressure set point from the adaptive control curve directly based at least partly on the following equation:

P*(t)=(Q*(t)/C_v^a(t))².

20. A method according to claim 12, wherein the method comprises determining with the processor the control set point based at least partly on the requested flow rate Q*(t) and derived from the adaptive set point control curve.

22. Apparatus comprising:

means for receiving signaling containing information about a linear set point control curve based at least partly on an adaptive set point control curve related to fluid being pumped by a pump in a pumping system, and

means for determining a control set point based at least partly on the signaling received.

23. Apparatus according to claim 22, wherein the apparatus further comprises means for providing a control signal containing information to control the pump based at least partly on the control set point determined.

24. Apparatus according to claim 22, wherein the means for determining determines a requested flow rate Q* based at least partly on the signaling containing information about an intersection point between the linear set point control curve and the adaptive set point control curve, including the intersection point at a maximum adaptive flow rate, Q_max.