Anti-entrapment and anti-deadhead function

• US 10,480,516 B2
• Filed: 12/21/2016
• Issued: 11/19/2019
• 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: 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): Hamo, Patrick
• Application Number:
  US15/386,993
• Publication Number:
  US 20170114788A1
• Time in Patent Office: 1,063 Days
• CPC Class Codes: F04B 49/20 by changing the driving speed
• 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 15/0077 Safety measures F04D15/02 takes precedence
• CPC Class Codes: F04D 15/0088 Testing machines
• CPC Class Codes: F04D 15/0254 the condition being speed or load
• CPC Class Codes: F05D 2270/335 Output power or torque

Abstract

In accordance with one aspect, the present disclosure provides for systems and methods for controlling a pumping system for at least one aquatic application. The pumping system can include a pump, a motor coupled to the pump, an interface associated with the pump designed to receive input instructions from a user, and a controller in communication with the motor. The controller determines a blockage condition based on a power consumption value of the motor, and can further include an auto-restart function that is designed to allow the pump to automatically restart after detection of the blockage.

Claims

1. A method of controlling a pumping system for at least one aquatic application having a pump driven by a motor coupled to the pump, the method comprising:

determining, via a controller in communication with the motor, whether a blockage condition exists based on a power consumption value of the motor,

wherein the blockage condition is at least one of an entrapment condition and a deadhead condition, and

wherein, if a blockage condition is detected,

restarting the pump after detection of the blockage condition,

undertaking a detection method in response to the entrapment condition, wherein the controller is alerted upon a first occurrence of a blockage event, or

undertaking another detection method in response to the deadhead condition, wherein the controller is alerted upon a plurality of blockage events.

2. The method of claim 1, wherein the power consumption value of the motor is determined using a previous power consumption value at a first time period and a current power consumption value determined at a second time period.

3. The method of claim 2, wherein the previous power consumption value is compared to the current power consumption value to determine a difference value.

4. The method of claim 1, wherein the controller continuously monitors the power consumption value to determine the blockage condition.

5. The method of claim 1, wherein the another detection method alerts the system upon a number of cumulative occurrences indicating the deadhead condition.

6. The method of claim 1, further comprising:

comparing a current power consumption value of the motor to a previously determined power consumption value to determine the entrapment condition;

or

comparing a deadhead baseline value with a current deadhead value to determine the deadhead condition.

7. A method for controlling a pumping system for at least one aquatic application having a pump coupled to a motor, the method comprising:

determining, via a controller in communication with the motor, whether a blockage condition exists by comparing a current power consumption value of the motor to one of;

a baseline value of power consumption of the motor, or

a previous power consumption value of the motor;

performing a condition check to determine whether a speed of the motor has recently changed;

shutting down the pumping system based on the comparison of the current power consumption value if the speed change did not occur during a transition or a stabilization stage of the speed change; and

calculating a power gradient baseline value based on the change in speed and corresponding oscillations in power consumption of the motor if the speed has recently changed.

8. The method of claim 7, wherein a difference value is determined based on the comparison of the current power consumption value of the motor to the previous power consumption value of the motor.

9. The method of claim 8, wherein the controller compares the difference value to the power gradient baseline value.

10. The method of claim 8 further comprising shutting down the motor substantially immediately if the difference value indicates a decrease in power consumption of the motor.

11. The method of claim 7, wherein the power gradient baseline value includes a trigger level capable of preventing erroneous triggering of an entrapment condition during speed change transition and setting times.

12. The method of claim 7 further comprising:

calculating a second power gradient baseline value based on a percentage of the current power consumption value of the motor.

13. The method of claim 12 further comprising triggering an entrapment condition if a present change in power consumption of the motor exceeds the percentage of the current power consumption value of the motor.

14. The method of claim 7 further comprising re-starting the pump using an auto-restart mechanism after determining that the speed change did not occur during the transition or stabilization stage of the speed change.

15. A method for controlling a pumping system having a pump that is coupled with a motor, the method comprising:

establishing, via a controller in communication with the motor, a baseline value of power consumption of the motor during a deadhead condition;

determining, via the controller, a current value of power consumption of the motor,

increasing a counter, via the controller, when the current value decreases below the baseline value, and

determining, via the controller, a deadhead condition caused by a blockage downstream from the pump when the counter exceeds a limit.

16. The method of claim 15, wherein the baseline value of power is dependent on a current speed of the motor.

17. The method of claim 15, wherein the baseline value is a percentage of a no flow power value, the no flow power value representing power consumed during a substantially complete blockage of downstream plumbing.

18. The method of claim 15, wherein the baseline value depends on user inputs related to a sensitivity of the pumping system, the user inputs being provided through a user interface.

19. The method of claim 15, wherein a decrease in power consumption of the motor is indicated by at least one of a relative amount of decrease, a comparison of decreased values, time elapsed since a decrease, and a number of consecutive decreases.

20. The method of claim 15, wherein a decrease in power consumption of the motor is based on a measurement of at least one of current and voltage provided to the motor, or at least one of a power factor, a resistance, and a friction of the motor, or a temperature of water in the aquatic application.

21. The method of claim 15 further comprising:

monitoring at least one of;

a power error determination,

a current motor speed compared to at least one of a maximum speed and a minimum speed,

a current motor speed compared to a previous motor speed, and

a speed change input received from a user interface.

22. The method of claim 15, further comprising:

monitoring at least one of;

a second controller,

a manual control system, and

a separate program running within the second controller providing at least one of;

a motor speed,

a power consumption value of the motor,

a flow rate, and

a pressure value.

23. The method of claim 15, wherein if the controller determines a deadhead condition, performing at least one of the following steps:

stopping the motor,

varying a speed of the motor,

displaying a visual indication,

locking out the motor until a specific action occurs by a user,

restarting the motor, and

restarting the motor after a time delay occurs.

24. A method of operating a pumping system for at least one aquatic application having a pump being electrically coupled with a motor, the method comprising:

comparing, via a controller in electrical communication with the motor, a current power consumption value of the motor to a substantially immediately previous power consumption value of the motor to determine a difference value;

shutting down the motor, via the controller, substantially immediately if the difference value indicates a sudden decrease in power consumption of the motor occurring during an entrapment condition caused by a blockage on a suction side of the pump;

performing a condition check, via the controller, to determine whether a speed of the motor has recently changed before shutting down the motor due to torque ripple; and

calculating a power gradient baseline value, via the controller, based on the change in speed.

25. The method of claim 24, wherein the power gradient baseline value includes a trigger level capable of preventing erroneous triggering of an entrapment condition during speed change transition and setting times, while permitting an entrapment condition in the event of a severe power gradient change.

26. A method of operating a pumping system for at least one aquatic application having a pump that is operatively coupled with a motor, the method comprising:

comparing, via a controller in communication with the motor, a current power consumption value of the motor to a substantially immediately previous power consumption value of the motor to determine a difference value;

shutting down the motor, via the controller, substantially immediately if the difference value indicates a sudden decrease in power consumption of the motor during an entrapment condition caused by a blockage on a suction side of the pump; and

performing a condition check, via the controller, to determine whether a speed of the motor has recently changed before shutting down the motor in order to avoid shutting down the motor due to torque ripple,

wherein if the speed has not recently changed, the controller calculates a power gradient baseline value based on a percentage of a present power consumption of the motor.

27. The method of claim 26, wherein an entrapment condition is triggered if a present change in power consumption of the motor exceeds the percentage of the present power consumption.