MULTIFUNCTION SENSOR SYSTEM FOR ELECTRICAL MACHINES

• US 20070296309A1
• Filed: 06/22/2006
• Published: 12/27/2007
• Est. Priority Date: 06/22/2006
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Younsi, Karim Abdelkrim, Seeley, Charles Erklin, Salem, Sameh Ramadan
• Granted Patent: US 7,508,119 B2
• Time in Patent Office: Days
• US Class Current: 310/338
• CPC Class Codes: G01D 21/02 Measuring two or more variables by means not covered by a single other subclass
• CPC Class Codes: H02K 11/20 for measuring, monitoring, testing, protecting or switching rectifiers H02K11/04; power electronics H02K11/33
• CPC Class Codes: H02K 11/25 Devices for sensing temperature, or actuated thereby
• CPC Class Codes: H02K 3/487 Slot-closing devices

Abstract

A multifunction sensor system for an electrical machine includes a piezoelectric vibration sensor a resistive temperature and partial discharge sensor which may optionally be integral with the piezoelectric vibration sensor; and packaging enclosing the vibration, the resistive temperature, and the partial discharge sensors.

Claims

1. A multifunction sensor system for an electrical machine comprising:

a piezoelectric vibration sensor;

a resistive temperature and partial discharge sensor;

packaging enclosing the vibration, resistive temperature, and partial discharge sensors,

2. The sensor system of claim 1 wherein the packaging has a thickness of less than or equal to ten millimeters.

3. The sensor system of claim 1 wherein the piezoelectric vibration sensor is integral with the resistive temperature and partial discharge sensor and comprises an integrated sensor.

4. The sensor system of claim 3 wherein the integrated sensor comprises a piezoelectric substrate comprising two opposing surfaces, a first side electrode overlying a first opposing surface, and a second side electrode overlying a second opposing surface.

5. The sensor system of claim 4 further comprising two coaxial cables comprising a first coaxial cable coupled to the second side electrode and a first end of the first side electrode and a second coaxial cable coupled to the second side electrode and a second end of the first side electrode.

6. The sensor system of claim 5 wherein the first side electrode comprises a serpentine shape.

7. The sensor system of claim 1 wherein the sensor comprises a piezoelectric substrate comprising two opposing surfaces, a first electrode facing a first opposing surface, and a second electrode facing a second opposing surface.

8. The sensor system of claim 7 wherein the piezoelectric substrate comprises polyvinylidene fluoride or lead zirconate titanate.

9. The sensor system of claim 7 further comprising coaxial cables coupled to the first and second electrodes, and a molding compound for securing the piezoelectric substrate, the first and second electrodes, and the coaxial cables.

10. The sensor system of claim 7 further comprising a second substrate and a third electrode situated on the sensor substrate.

11. The sensor system of claim 10 wherein the second electrode comprises a ground plane situated between the piezoelectric substrate and the second substrate, the piezoelectric vibration sensor comprises the piezoelectric substrate and the first and second electrodes, and the resistive temperature and partial discharge sensor comprises the second substrate and the second and third electrodes.

12. A multifunction sensor system for an electrical machine comprising:

an integral piezoelectric vibration, partial discharge, and resistive temperature sensor comprising a piezoelectric substrate comprising two opposing surfaces, a first side electrode overlying a first opposing surface, and a second side electrode overlying a second opposing surface;

cables selectively coupled to the first and second side electrodes; and

packaging enclosing the sensor.

13. The sensor system of claim 12 further comprising two coaxial cables comprising a first coaxial cable coupled to the second side electrode and a first end of the first side electrode and a second coaxial cable coupled to the second side electrode and a second end of the first side electrode.

14. The sensor system of claim 12 wherein the first side electrode comprises a serpentine shape.

15. The sensor system of claim 14 wherein the serpentine shape comprises a square wave, a triangular wave, or a curved wave.

16. The sensor system of claim 12 wherein the piezoelectric substrate is selected from the group of monolithic piezoelectric substrates and embedded-fiber piezoelectric substrates.

17. An electric generator comprising:

a stator comprising stator slots and stator bars situated within the stator slots;

a sensor system situated within a stator slot, the sensor system comprising a piezoelectric vibration sensor, a resistive temperature and partial discharge sensor, and packaging enclosing the vibration, resistive temperature, and partial discharge sensors.

18. The electric generator of claim 17 wherein the sensor system is situated between adjacent stator bars in the stator slot.

19. The electric generator of claim 17 wherein the stator further comprises stator wedges situated within the stator slots, and wherein the sensor system is situated in the stator slot between a stator wedge and a stator bar.