Flow Control

• US 20110076156A1
• Filed: 12/01/2010
• Published: 03/31/2011
• 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: Lungeanu, Florin, Kjaer, Gert, Berthelsen, Lars Hoffmann, Westermann-Rasmussen, Peter, Stiles, Robert W. JR.
• Granted Patent: US 8,801,389 B2
• Time in Patent Office: Days
• US Class Current: 417/42
• CPC Class Codes: F04B 2203/0208 Power
• CPC Class Codes: F04B 2203/0209 Rotational speed
• CPC Class Codes: F04B 2205/05 Pressure after the pump outlet
• CPC Class Codes: F04B 2205/09 Flow through the pump
• CPC Class Codes: F04B 49/065 and making use of computers
• CPC Class Codes: F04B 49/106 Responsive to pumped volume
• CPC Class Codes: F04B 49/20 by changing the driving speed
• CPC Class Codes: F04B 49/22 by means of valves F04B49/03 takes precedence
• CPC Class Codes: F04D 13/06 the pump being electrically driven
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• CPC Class Codes: F04D 15/0227 Lack of liquid level being detected using a flow transducer
• CPC Class Codes: F04D 15/0236 Lack of liquid level being detected by analysing the parameters of the electric drive, e.g. current or power consumption

Abstract

A pumping system for moving water of a swimming pool includes a water pump and a variable speed motor. The pumping system further includes means for determining a first motor speed of the motor, means for determining first and second performance values of the pumping system, and means for comparing the first and second performance values. The pumping system further includes means for determining an adjustment value based upon the comparison, means for determining a second motor speed based upon the adjustment value, and means for controlling the motor in response to the second motor speed. In one example, the pumping system includes means for determining a value indicative of a flow rate of water moved by the pump. In addition or alternatively, the pumping system includes a filter arrangement. A method of controlling the pumping system for moving the water of the swimming pool is also disclosed.

Claims

1. A pumping system for at least one aquatic application, the pumping system comprising:

a pump;

a motor coupled to the pump; and

a controller in communication with the motor, the controller determining a first motor speed, the controller obtaining a reference flow rate, the controller determining a reference power consumption based on the first motor speed and the reference flow rate, the controller determining a present power consumption, the controller calculating a difference value between the reference power consumption and the present power consumption, the controller using at least one of integral, proportional, and derivative control to generate a second motor speed based on the difference value, and the controller attempting to drive the motor at the second motor speed until reaching a steady state condition.

2. The pumping system of claim 1, wherein a reference estimator determines the reference power consumption by at least one of calculation, a look-up table, a graph, and a curve.

3. The pumping system of claim 2, wherein the reference estimator uses curves of power versus speed for discrete flow rates to determine the reference power consumption.

4. The pumping system of claim 1, wherein the reference flow rate is calculated based on at least one of a volume of the at least one aquatic application, a number of turnovers desired per day, and a time range that the pumping system is permitted to operate.

5. A pumping system for at least one aquatic application, the pumping system comprising:

a pump;

a motor coupled to the pump; and

a controller in communication with the motor, the controller determining a first motor speed, the controller obtaining a reference flow rate, the controller determining a present flow rate, the controller determining a present power consumption, the controller calculating a difference value between the reference flow rate and the present flow rate, the controller using at least one of integral, proportional, and derivative control to generate a second motor speed based on the difference value, and the controller attempting to drive the motor at the second motor speed until reaching a steady state condition.

6. The pumping system of claim 5, wherein the first motor speed is determined from a present shaft speed of a synchronous motor.

7. The pumping system of claim 5, wherein the reference flow rate is calculated based on at least one of a volume of the at least one aquatic application, a number of turnovers desired per day, and a time range that the pumping system is permitted to operate.

8. The pumping system of claim 5, wherein a flow estimator determines the present flow rate by at least one of calculation, a look-up table, a graph, and a curve.

9. The pumping system of claim 8, wherein the flow estimator uses curves of speed versus flow rate for discrete power consumptions to determine the present flow rate.

10. The pumping system of claim 5, wherein the present power consumption is based on at least one of current and voltage provided to the motor.

11. The pumping system of claim 5, wherein the present power consumption is based on at least one of a power factor, resistance, and friction of the motor.