Control Algorithm of Variable Speed Pumping System

• US 20120063921A1
• Filed: 09/12/2011
• Published: 03/15/2012
• Est. Priority Date: 08/26/2004
• Status: Active Grant

• Current Assignee: Danfoss Power Electronics A/S (Danfoss A/S), Pentair Water Pool And Spa Incorporated (Pentair Plc (Ireland))
• Original Assignee: Danfoss Power Electronics A/S (Danfoss A/S)
• Inventors: Stiles, Robert W. Jr., Robol, Ronald B., Harvest, Nils-Ole, Cox, Everett, Steen, Donald, Murphy, Kevin, Hruby, Daniel J., Westermann-Rasmussen, Peter, Kjaer, Gert, Berthelsen, Lafs Hoffmann
• Granted Patent: US 9,404,500 B2
• Time in Patent Office: Days
• US Class Current: 417/42
• CPC Class Codes: F04B 49/065 and making use of computers
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• CPC Class Codes: F04D 15/0088 Testing machines
• CPC Class Codes: F04D 9/004 Priming of not self-priming pumps

Abstract

A pumping system includes a pump for moving water. In one aspect, this is in connection with performance of an operation. The system includes a variable speed motor operatively connected to drive the pump. A value indicative of flow rate of water is determined and the motor is controlled to adjust the flow rate indicative value toward a constant. A value indicative of flow pressure is determined and the motor is controlled to adjust the flow pressure indicative value toward a constant. A selection is made between flow rate control and flow pressure control. In another aspect, the pump is controlled to perform a first operation, and is operated to perform a second water operation. Control of operation of the pump to perform the first water operation is altered in response to operation of the pump to perform the second operation.

Claims

1. A variable speed pumping system capable of moving a fluid within a fluid circuit, comprising:

a pump in fluid communication with the fluid and the fluid circuit;

a variable speed motor coupled to the pump to drive the pump;

a controller in communication with the variable speed motor to control operation of the variable speed motor; and

a user interface in communication with the controller;

wherein the controller controls the variable speed motor such that the variable speed motor operates approximately below a predetermined threshold.

2. The variable speed pumping system of claim 1, wherein the predetermined threshold comprises at least one of a flow rate of the fluid within the fluid circuit, a pressure of the fluid within the fluid circuit, an input power of the variable speed motor, and a speed of the variable speed motor.

3. The variable speed pumping system of claim 1, wherein the predetermined threshold is entered to the controller through the user interface.

4. The variable speed pumping system of claim 1, wherein the controller monitors at least one of the variable speed motor and a sensor to control the operation of the variable speed motor.

5. The variable speed pumping system of claim 1, further comprising a sensor in communication with the controller and at least one of the variable speed motor and the fluid circuit to sense a parameter, wherein the controller monitors the sensor and adjusts the operation of the variable speed motor in response to the parameter to maintain operation of the variable speed motor at a specific level.

6. The variable speed pumping system of claim 5, wherein the specific level is at least one of a minimum level to maintain a specific flow rate of the fluid through the fluid circuit, a minimum level to maintain a specific pressure of the fluid within the fluid circuit, a maximum level below the predetermined threshold, and a maximum input power of the variable speed motor.

7. The variable speed pumping system of claim 5, wherein the sensor is at least one of a flow rate sensor sensing a flow rate of the fluid through the fluid circuit, a pressure sensor sensing a pressure of the fluid within the fluid circuit, a voltage sensor sensing the voltage applied to the variable speed motor, and a current sensor sensing a current draw by the variable speed motor.

8. The variable speed pumping system of claim 1, wherein the controller maintains at least one of a substantially constant flow rate of the fluid within the fluid circuit and a substantially constant pressure of the fluid within the fluid circuit.

9. The variable speed pumping system of claim 1, wherein:

the controller is configured to perform a first water operation; and

the predetermined threshold is adjusted in response to the first operation.

10. The variable speed pumping system of claim 1, further comprising a variable speed drive in communication with the controller to control the operation of the variable speed motor between a minimum rate and a maximum rate.

11. The variable speed pumping system of claim 10, wherein the variable speed drive supplies a direct current to the variable speed motor to control the operation of the variable speed motor.

12. A variable speed pumping system capable of moving a fluid within a fluid circuit, comprising:

a pump in fluid communication with the fluid and the fluid circuit;

a variable speed motor coupled to the pump to drive the pump;

a controller in communication with the variable speed motor to control operation of the variable speed motor;

a user interface in communication with the controller; and

a sensor in communication with the controller and at least one of the variable speed motor and the fluid circuit to sense a parameter;

wherein the controller monitors the sensor and adjusts the operation of the variable speed motor in response to the parameter to maintain operation of the variable speed motor at a specific level.

13. The variable speed pumping system of claim 12, wherein the specific level is at least one of a minimum level to maintain a specific flow rate of the fluid through the fluid circuit, a minimum level to maintain a specific pressure of the fluid within the fluid circuit, a maximum level below a predetermined threshold, and a maximum input power of the variable speed motor.

14. The variable speed pumping system of claim 12, wherein the sensor is at least one of a flow rate sensor sensing a flow rate of the fluid through the fluid circuit, a pressure sensor sensing a pressure of the fluid within the fluid circuit, a voltage sensor sensing the voltage applied to the variable speed motor, and a current sensor sensing a current draw by the variable speed motor.

15. The variable speed pumping system of claim 12, wherein the controller adjusts the operation of the variable speed motor to maintain operation of the variable speed motor at the specific level such that at least one of a substantially constant flow rate of the fluid throughout the fluid circuit and a substantially constant pressure of the fluid within the fluid circuit is maintained.

16. The variable speed pumping system of claim 12, wherein:

the controller is configured to perform a first water operation;

the specific level is adjusted in response to the first operation.

17. The variable speed pumping system of claim 16, wherein the specific level is adjusted between a minimum rate and a maximum rate.