Controller for a motor and a method of controlling the motor

• US 20080095638A1
• Filed: 10/13/2006
• Published: 04/24/2008
• Est. Priority Date: 10/13/2006
• Status: Abandoned Application

• Current Assignee: Regal Beloit Epc Inc. (Regal Rexnord Corp.)
• Original Assignee: A. O. Smith Corporation
• Inventors: Branecky, Brian Thomas
• Application Number:
  US11/549,518
• Publication Number:
  US 20080095638A1
• Time in Patent Office: Days
• US Class Current: 417/43
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• 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
• CPC Class Codes: F04D 15/0254 the condition being speed or load
• CPC Class Codes: H02P 29/024 Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load

Abstract

A pumping apparatus for a jetted-fluid system includes a pump having an inlet connectable to the drain, and an outlet connectable to the return. The pump is adapted to receive the fluid from the drain and jet fluid through the return. The apparatus includes a motor coupled to the pump to operate the pump, a sensor configured to generate a signal having a relation to a parameter of the motor, and a switch coupled to the motor and configured to control at least a characteristic of the motor. The apparatus also includes a microcontroller coupled to the sensor and the switch. The microcontroller includes a model observer configured to receive a first value based on the signal and to generate a second value representative of at least one of a modeled flow or a modeled pressure based on the first value. The microcontroller is configured to control the motor based on the second value.

Claims

1. A pumping apparatus for a jetted-fluid system comprising a vessel for holding a fluid, a drain, and a return, the pumping apparatus being connectable to a power source and comprising:

a pump including an inlet connectable to the drain, and an outlet connectable to the return, the pump adapted to receive the fluid from the drain and jet fluid through the return;

a motor coupled to the pump to operate the pump;

a sensor configured to generate a signal having a relation to a parameter of the motor;

a switch coupled to the motor and configured to control at least a characteristic of the motor; and

a microcontroller coupled to the sensor and the switch, the microcontroller including a model observer configured to receive a first value based on the signal and to generate a second value representative of at least one of a modeled flow or a modeled pressure based on the first value, the microcontroller configured to control the motor based on the second value.

2. The pumping apparatus of claim 1, wherein the sensor includes a voltage sensor configured to generate a first signal having a relation to a voltage applied to the motor, and a current sensor configured to generate a second signal having a relation to a current applied to the motor, and wherein the microcontroller is configured to generate the first value based on the first signal and the second signal.

3. The pumping apparatus of claim 1, wherein the sensor includes a voltage sensor and a current sensor, and wherein the first value includes a motor power value.

4. The pumping apparatus of claim 1, wherein first value includes a motor torque value.

5. The pumping apparatus of claim 1, wherein the model observer includes a model that simulates the pumping apparatus.

6. The pumping apparatus of claim 1, wherein the model observer includes a model that simulates at least part of the jetted-fluid system.

7. The pumping apparatus of claim 1, wherein the microcontroller is further configured to

monitor the second value,

determine whether the monitored second value indicates an undesired flow of fluid through the pump, and

control the motor to cease operation of the pump when the determination indicates an undesired flow of fluid through the pump and zero or more other conditions exist.

8. A pumping apparatus for a jetted-fluid system comprising a vessel for holding a fluid, a drain, and a return, the pumping apparatus being connectable to a power source and comprising:

a pump including an inlet connectable to the drain, and an outlet connectable to the return, the pump adapted to receive the fluid from the drain and jet fluid through the return;

a motor coupled to the pump to operate the pump;

a sensor configured to generate a signal having a relation to a parameter of the motor;

a switch coupled to the motor and configured to control at least a characteristic of the motor; and

a microcontroller coupled to the sensor and the switch, the microcontroller including a model observer configured to receive a first value based on the signal and to generate a second value representative of a modeled pressure based on the first value, the microcontroller configured to control the motor based on the second value.

9. The pumping apparatus of claim 8, wherein the sensor includes a voltage sensor configured to generate a first signal having a relation to a voltage applied to the motor, and a current sensor configured to generate a second signal having a relation to a current applied to the motor, and wherein the microcontroller is configured to generate the first value based on the first signal and the second signal.

11. The pumping apparatus of claim 8, wherein the sensor includes a voltage sensor and a current sensor, and wherein the first value includes a motor power value.

12. The pumping apparatus of claim 8, wherein first value includes a motor torque value.

13. The pumping apparatus of claim 8, wherein the model observer includes a model that simulates the pumping apparatus.

14. The pumping apparatus of claim 8, wherein the model observer includes a model that simulates at least part of the jetted-fluid system.

15. The pumping apparatus of claim 8, wherein the microcontroller is further configured to

monitor the second value,

determine whether the monitored second value indicates an undesired flow of fluid through the pump, and

control the motor to cease operation of the pump when the determination indicates an undesired flow of fluid through the pump and zero or more other conditions exist.

16. A method of controlling a motor operating a pumping apparatus of a jetted fluid system comprising a vessel for holding a fluid, a drain, and a return, the pumping apparatus comprising a pump having an inlet connectable to the drain, and an outlet connectable to the return, the pump adapted to receive the fluid from the drain and jet fluid through the return, and the motor coupled to the pump to operate the pump, the method comprising:

determining a power of the pump motor;

applying the power to a model observer;

obtaining a value representative of a flow based on the power and the model observer;

determining whether the value indicates a condition of the pump; and

controlling the motor to operate the pump based on the condition of the pump.

17. The method of claim 16, wherein monitoring the operation of the pump further comprises

determining a torque of the motor;

and

applying the torque to the model observer.

18. The method of claim 16, wherein monitoring the operation of the pump further comprises providing the model observer with a fluid system model simulating at least a portion of the jetted-fluid system.

19. The method of claim 16, wherein determining whether the value indicates a condition of the pump further comprises

determining a trip value;

and

comparing the value with the trip value.

20. A method of controlling a motor operating a pumping apparatus of a jetted fluid system comprising a vessel for holding a fluid, a drain, and a return, the pumping apparatus comprising a pump having an inlet connectable to the drain, and an outlet connectable to the return, the pump adapted to receive the fluid from the drain and jet fluid through the return, and the motor coupled to the pump to operate the pump, the method comprising:

determining a power of the pump motor;

applying the power to a model observer;

obtaining a value representative of a pressure based on the power and the model observer;

determining whether the value indicates a condition of the pump; and

controlling the motor to operate the pump based on the condition of the pump.

21. The method of claim 20, wherein monitoring the operation of the pump further comprises

determining a torque of the motor;

and

applying the torque to the model observer.

22. The method of claim 20, wherein monitoring the operation of the pump further comprises providing the model observer with a fluid system model simulating at least a portion of the jetted-fluid system.

23. The method of claim 20, wherein determining whether the value indicates a condition of the pump further comprises

determining a trip value;

and

comparing the value with the trip value.

24. A method of controlling a fluid-movement system including a motor and a pump, the motor being coupled to the pump to operate the pump, the method comprising:

calibrating the system to obtain a calibration value for a motor parameter;

obtaining a relationship between the motor parameter and a fluid parameter;

determining a trip value based on the calibration value and the relationship;

controlling the motor to operate the pump;

monitoring the operation of the pump, the monitoring act including

determining a value for the motor parameter,

comparing the value to the trip value, and

determining whether the comparison indicates a condition of the pump; and

further controlling the motor to operate the pump based on the condition of the pump.

25. The method of claim 24, wherein the fluid parameter includes a flow rate.

26. The method of claim 24, wherein the fluid parameter includes a pressure of the pump

27. The method of claim 24, wherein the motor parameter includes motor input power.

28. The method of claim 24, wherein the motor parameter includes motor torque.

29. The method of claim 24, wherein the determining a trip value includes determining at least one characterization value based on the motor and the pump, and determining the trip value based on the at least one characterization value and the calibration value.

30. The method of claim 24, wherein the calibrating the system includes calculating a calibration value related to torque.

31. The method of claim 24, wherein the determining a trip value includes obtaining a second value based on the calibration value and the relationship, and wherein the calculating the trip value includes determining a percentage reduction of the second value.

32. The method of claim 24, wherein the controlling the motor based on the condition of the pump includes inhibiting current through the motor to stop operation of the pumping apparatus.

33. The method of claim 24, wherein the relationship includes an equation relating the fluid parameter and the motor parameter.

34. The method of claim 24, wherein the relationship includes a table relating the fluid parameter and the motor parameter.

35. A method of controlling a fluid-movement system including a motor and a pump, the motor being coupled to the pump to operate the pump, the method comprising:

determining a relationship between an input power to the motor and a flow rate through the pump;

determining a calibration value for the input power;

determining a percentage drop for the relationship;

determining a trip value based on the relationship, the calibration value, and the percentage drop;

monitoring the operation of the pump, the monitoring act comprising

determining a first value for the input power,

comparing the first value to the trip value, and

determining whether the first value indicates a condition of the pump; and

controlling the motor to operate the pump based on the condition of the pump.

36. The method of claim 35, wherein the controlling the motor based on the condition of the pump includes inhibiting current through the motor to stop operation of the pumping apparatus.

37. The method of claim 35 the determining a trip value includes applying the calibration value to the relationship to result in a flow rate value, adjusting the flow rate value by a percentage, applying the flow rate value to the relationship to result in the trip value.

38. The method of claim 35, wherein the relationship includes an equation relating the fluid parameter and the motor parameter.

39. The method of claim 35, wherein the relationship includes a table relating the fluid parameter and the motor parameter.