Integrated motor and diagnostic apparatus and method of operating same

• US 5,917,428 A
• Filed: 11/07/1996
• Issued: 06/29/1999
• Est. Priority Date: 11/07/1996
• Status: Expired due to Term

• Current Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Original Assignee: Reliance Electric Industrial Company (ABB Limited)
• Inventors: Discenzo, Frederick M., Tompkin, Edward J., DelVecchio, Perry A.
• Primary Examiner(s): Horabik, Michael
• Assistant Examiner(s): WONG, ALBERT KANG
• Application Number:
  US08/745,167
• Time in Patent Office: 964 Days
• Field of Search: 376/245, 340/870.01, 340/870.17, 340/870.07, 340/870.05, 340/648, 364/146, 364/552, 324/177, 324/772, 73/659, 318/490, 310/68 R, 310/68 B, 310/68 C, 307/116
• US Class Current: 340/870.01
• CPC Class Codes: G01R 31/343 in operation

Abstract

A method and apparatus for real-time electric motor diagnostics and condition monitoring. While the motor is energized, dynamic operating parameters are determined and a notification signed is generated if predetermined criterion are satisfied. The diagnostic apparatus is integrated with the motor and includes a set of sensors, a processing unit, a memory and an output interface for communicating alarms, warnings and calculated operating parameter values or the like to a display device and to an external supervisor having wireless paging capability to alert a remote operator or maintenance personnel. In a normal operating mode, the processing unit calculates a general class of derived motor operating parameters such as over-temperature, over-voltage, over-current, excessive vibration, and phase imbalance. When an abnormal condition is observed, the processing unit modifies certain data acquisition parameters as necessary to effect an alternative data acquisition strategy which would more likely lead to data dispositive of the condition of the motor.

Claims

1. An integrated motor and diagnostic system comprising:

an electric motor including a rotor, a stator, at least one bearing supporting the rotor, and a plurality of motor lead wires carrying electrical current to the motor; and

,

a diagnostic unit integrated into the electric motor, the diagnostic unit including;

at least one sensor on the motor for measuring a first physical condition of the motor and generating a first physical condition signal based on said measured fist physical condition;

a memory element including an FFT based diagnostic algorithm;

a processing unit coupled to said memory element and to said at least one sensor, said processing unit performing a diagnostic assessment of the motor based on said first physical condition signal and the diagnostic algorithm and generating a diagnostic signal; and

,

a signal communicating unit coupled to the processing unit for communicating the diagnostic signal from the diagnostic apparatus.

2. The integrated motor and diagnostic system according to claim 1 wherein:

said diagnostic unit further comprises a plurality of sensors on the motor for measuring a plurality of first physical conditions of the motor and generating a plurality of first physical condition signals based on said plurality of first physical conditions; and

,

said processing unit is connected to said plurality of sensors for determining said diagnostic assessment of the motor based on first preselected ones of said plurality of first physical condition signals and the diagnostic algorithm.

3. The integrated motor and diagnostic system according to claim 2 wherein said plurality of sensors include a set of sensors selected from the group consisting of a vibration sensor, a thermocouple sensor, an electric current sensor, an electric voltage sensor and a magnetic flux sensor.

4. The integrated motor and diagnostic system according to claim 1 further comprising a supervisory computer device operatively connected to the signal communicating unit for receiving said motor diagnostic signal from the signal communicating unit and selectively generating a diagnostic message based on said motor diagnostic signal.

5. The integrated motor and diagnostic system according to claim 4 wherein said supervisory computer device is adapted to communicate said diagnostic message to an operatively associated commercial pager system for transmission to a remote alphanumeric pager device.

6. The integrated motor and diagnostic system according to claim 1 wherein the processing unit includes means for comparing said diagnostic signal with a first operating condition parameter stored in said memory.

7. The integrated motor and diagnostic system according to claim 6 wherein the signal communicating unit includes an operator interface having an input unit for receiving said first operating condition parameter into the system and an output unit for displaying said motor diagnostic signal.

8. The integrated motor and diagnostic system according to claim 7 wherein:

the input unit of the said operator interface includes means for receiving said first operating condition parameter from an operatively associated supervisory controller; and

,

the output unit of said operator interface includes means for transmitting said motor diagnostic signal to said operatively associated supervisory controller.

9. The integrated motor and diagnostic system according to claim 1 wherein:

said system further comprises a plurality of sensors on the motor for measuring a plurality of first physical conditions of the motor and generating a plurality of first physical condition signals based on said plurality of measured first physical conditions; and

,

said processing unit includes means for dynamically adjusting a sampling rate of selective ones of said plurality of sensors based on an operating condition of the motor.

10. The integrated motor and diagnostic system according to claim 1 wherein said electric motor includes a housing adapted to integrally couple with said diagnostic unit.

11. An integrated motor and diagnostic system comprising:

an electric motor including a rotor, a stator, at least one bearing supporting the rotor and, a plurality of motor lead wires carrying electric current to the motor; and

,

a diagnostic unit integrated into the electric motor, the diagnostic unit including;

at least one sensor measuring a first physical condition of the motor and generating a first physical condition signal based on said measured first physical condition;

a memory element including a pattern recognition based diagnostic algorithm;

a processing unit coupled to said memory element and to said at least one sensor, said processing unit performing a diagnostic assessment of the motor based an said first physical condition signal and the diagnostic algorithm and generating a diagnostic signal; and

,

a display device integrated into the electric motor and adapted to visually display said diagnostic signal of the motor.

12. The integrated motor and diagnostic system according to claim 11 further comprising a signal communicating unit responsive to the processing unit for communicating said diagnostic signal from the integrated motor and diagnostic system to an operatively associated external supervisory computer device.

13. The integrated motor and diagnostic system according to claim 12 further comprising a supervisory computer device operatively connected to the signal communicating unit for receiving said diagnostic signal from the signal communicating unit and selectively generating a diagnostic message at the supervisory computer device based on said first operating condition signal.

14. A integrated motor and diagnostic system comprising:

an electric motor including a rotor, a stator, at least one bearing supporting the rotor and, a plurality of motor lead wires carrying electric current to the motor; and

,

a diagnostic unit integrated into the electric motor, the diagnostic unit including;

a plurality of sensors measuring a plurality of physical conditions of the motor and generating a plurality of physical condition signals based on said measured plurality of physical conditions;

a memory element including an FFT based diagnostic algorithm;

a processing unit coupled to said memory element and to said plurality of sensors, said processing unit performing a diagnostic assessment of the motor based on said plurality of physical condition signals and said diagnostic algorithm and generating a diagnostic signal; and

,

a signal communicating unit responsive to the processing unit and adapted to communicate said physical condition signal and said diagnostic signal from the diagnostic apparatus to an operatively associated external device.

15. The integrated motor and diagnostic system according to claim 14 further comprising a supervisory computer device operatively connected to the signal communicating unit adapted to receive said diagnostic signal from the signal communicating unit and selectively generate a diagnostic message at the supervisory computer device based on said diagnostic signal.

16. The integrated motor and diagnostic system according to claim 15 wherein said diagnostic unit includes a display device integrated into the electric motor and adapted to visually represent said diagnostic signal.

17. The integrated motor and diagnostic system according to claim 16 wherein said plurality of sensors include a set of sensors selected from the group consisting of a vibration sensor, a thermocouple sensor, an electric current sensor, an electric voltage sensor and a magnetic flux sensor.

18. A motor diagnostic system comprising:

an electric motor;

a diagnostic unit integrated into said motor, said diagnostic unit comprising,

at least one sensor measuring a first physical condition of the motor and generating a first physical condition signal based an said first physical condition;

a memory element including a motor model based diagnostic algorithm;

a processing unit coupled to said memory element and to said at least one sensor, said processing unit performing a diagnostic assessment of the motor based on said first physical condition signal and the diagnostic algorithm and generating a diagnostic signal; and

a remote signal communications interface coupled to the processing unit for communicating said diagnostic signal and said first physical condition signal.

19. The motor diagnostic system according to claim 18 further comprising a supervisory computer device operatively connected to the remote communications interface for receiving said first physical condition signal from the interface and selectively generating a diagnostic message at the supervisory computer device based on said first physical condition signal.