Flow control

• US 9,777,733 B2
• Filed: 07/01/2014
• Issued: 10/03/2017
• 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 Drives A/S (Danfoss A/S), Pentair Water Pool And Spa Incorporated (Pentair Plc (Ireland))
• Inventors: Stiles, Jr., Robert W., Berthelsen, Lars Hoffmann, Westermann-Rasmussen, Peter, Kjaer, Gert, Lungeanu, Florin
• Primary Examiner(s): Bertheaud, Peter J
• Application Number:
  US14/321,639
• Publication Number:
  US 20140314582A1
• Time in Patent Office: 1,190 Days
• Field of Search: 417 20, 417 22, 417 441, 417 42, 417 43
• 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 at least one aquatic application comprises a motor coupled to a pump and a controller in communication with the motor. The controller may be adapted to determine a first motor speed, determine a present flow rate using curves of speed versus flow rate for discrete power consumptions, generate a difference value between the present flow rate and a reference flow rate, and/or drive the motor at a second motor speed based on the difference value until reaching a steady state condition.

Claims

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

a motor coupled to a pump; and

a controller in communication with the motor;

the controller adapted to determine a first motor speed;

the controller adapted to determine a present flow rate using curves of speed versus flow rate for discrete power consumptions;

the controller adapted to generate a difference value between the present flow rate and a reference flow rate;

the controller driving the motor to reach a steady state condition at a second motor speed based on the difference value.

2. The pumping system of claim 1, the system comprising a reference estimator adapted to determine a reference power consumption by at least one of calculation, a look-up table, a graph, and/or a curve.

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

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

5. The pumping system of claim 1, wherein the first motor speed is determined from, a present shaft speed of a synchronous motor.

6. The pumping system of claim 1, wherein the controller is adapted to determine a present power consumption based on at least one of a current and/or a voltage provided to the motor.

7. The pumping system of claim 1, wherein the controller is adapted to determine a present power consumption based on at least one of a power factor, a resistance, and/or a friction of the motor.

8. A method of controlling a pumping system comprising a controller, a motor, and a pump, the controller in communication with the motor, the motor coupled to the pump, the method comprising:

determining, using curves of speed versus flow rate for discrete power consumptions, a present flow rate based on a first motor speed of the motor and a present power consumption of the motor; and

driving the motor to reach a steady state condition at a second motor speed based, on a difference value between a reference flow rate, and the present flow rate.

9. The method of claim 8, wherein the first motor speed is determined directly from a sensor reading a present shaft speed.

10. The method of claim 8, wherein the first motor speed is determined from a present shaft speed of a synchronous motor.

11. The method of claim 8, wherein the reference flow rate is based on at least one of a volume of at least one aquatic application, a number of turnovers desired per day, and/or a time range that the pumping system is permitted to operate.

12. The method of claim 8, wherein the present power consumption is based on at least one of a current and/or a voltage provided to the motor.

13. The method of claim 8, wherein the present power consumption is based on at least one of a power factor, a resistance, and/or a friction of the motor.