Vibration Sources in Electric MotorsEdward Jenkins, P.E., Ph.D.. Radial Forces – Frequency of Supply- Poles... Radial Forces - Slot Passing... Axial Forces - Magnetic Center... Axial For
Trang 1Vibration Sources in Electric Motors
Edward Jenkins, P.E., Ph.D Wayne Hall, P.E.
Jenkins Electric Company
Trang 2Electrical Sources of Pulsating Force
Trang 3Rotational - Tangential Force
Trang 4Rotor
Trang 5Brake
Trang 6Radial Forces
Trang 7Unbalanced Magnetic Fields
Trang 8Radial Forces – Frequency of Supply- Poles
Trang 9Radial Forces - Slot Passing
Trang 10Axial Forces - Magnetic Center
Trang 11Axial Forces - Air Passages
Trang 12Axial Forces – Rotor Cage
Trang 13Winding Failures - Inter-phase Fault
Trang 14Ground Fault
Trang 15Open Sections
Trang 17Broken Rotor Bars
Trang 18Power Supply and Drives
• Unbalanced Voltage Supply
• Intermittent Connections
• Pulsing from the Drive
• Harmonics from the Drive
• Encoder/Feedback Devices
Trang 19Unbalanced Supply Voltage
Trang 20Intermittent Connections
Trang 21Harmonics from Drive
Trang 22Power Supply/Drives
- Encoder/ Feedback faults
Trang 24Rotating Mass
Trang 25Coupling and Key
Trang 26Rotating Mass – Fan Blade
Trang 27Eccentricity – Rotor Air Gap
Trang 28Eccentricity – Bearing
Trang 29Roughness in Bearing
Trang 30Roughness in Gears
Trang 31Load
Trang 32Rubbing
Trang 33Rubbing - Bearing
Trang 34Misalignment
Trang 35Air Passages in Stator and Rotor
Trang 36Warped Frame
Trang 37Water or Electric Supply Piping
Trang 38Amplifier Effects
• Resonance
• Soft Foot - Rocking
• Looseness
Trang 39Amplifier Effects - Resonance
Trang 40Amplifier Effects – Soft Foot
Trang 41Amplifier Effects –
Looseness Bearing Journal
Trang 42Amplifier Effects –
Looseness Bearing Housing
Trang 43Rotor and Sleeve Journal
Trang 44Amplifier Effects - Looseness – Stator Core
L = Ds
2M
Trang 45Amplifier Effects - Looseness – Pedestal
Trang 46Armature Winding
Trang 47Inside Out Motor
Trang 481 William R Finley, Mark M Hodowanec, and Warren G
Holter, “An analytical approach to solving motor
vibration problems,” EASA Tech Note 40, Electrical
Apparatus Service Association, Inc., St Lousi, March
2002, 16 pages.
2 Tom Bishop, “Motor and drive system resonance
problems and solutions,” EASA Currents, pages 4 to 8,
March 2007.
3 Richard L Nailen, Managing Motors, Barks
Publications, Inc Chicago, 1991.
4 S.A Naser, Handbook of Electric Machines,
McGraw-Hill, NY, 1987.