Electric Motor Fault by Causes

Electric Motor Fault by Causes

Internal Causes

Electrical

• Stator Faults
• Insulation faults
• Rotor Faults

Mechanical

• Fraction/abrasion
• Displacement of conductors
• Bearing Faults
• Eccentricity
• bent shaft
• misalignment
• cooling fan
• irregularities with the connected mechanical load (overloading and load oscillations).

External Causes

Electrical

• Transient
• Voltage fluctuation
• Voltage imbalance

Mechanical

• Pulsating torque
• Improper installation
• Overload
• External magnetic field

Environmental

• Temperature
• Fouling
• Humidity
• Air acidity
• Dust

Origins

• electrical origins:
• mechanical causes:
• thermal stresses:
• environmental reasons:

Consequences

• magnetic field distortion ⭢ sensed by magnetic sensor
• overheating ⭢ sensed by temperature sensor
• electric arcs
• vibration effects ⭢ sensed by accelerometer
• abnormally high or destructive currents ⭢ sensed by current sensor
• electromechanical torque oscillation
• noise
• additional torque
• stator damages

Fault Classification Diagram

Fault Distributions

bldc-fault

Classification

• Mechanical Faults (50% of BLDC failures)

Winding failure (Kudelina et al., 2020)

Effects

• High temperature (core, winding)
• Electrical discharges
• Environmental pollution
• Short circuit

Fault Diagnostic in BLDC

• Invasive Techniques
• Non ivnasive Techniques

Fault Diagnostic Techniques

• Temperature meeasurement
• Electromagnetic field monitoring
• Radio frequency emissions monitoring
• Chemical analysis
• Acoustic noise measurement
• Motor-current signature analysis (MCSA)
• Noise and vibration monitoring
• Model and data-driven based

Signal Processing techniques (Kudelina et al., 2020)

References

• (Kudelina et al., 2020)

Cross-references

Electric Motor Fault by Components

References

• (benbouzidSignalProcessingFault2020, link, DOI)
• cardosoDiagnosisFaultTolerance2018