MP7.Motor Current Signature Analysis Flashcards
Direct failure modes
Which kind of direct failures that can have in a Induction motor
Stator
Which kind of direct failures that can have in a Induction motor
Bearings
Which kind of direct failures that can have in a Induction motor
Rotor
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them
Machine mismatch–We are interest in this failure modes because here we can find the cause (RCA)
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them
Maintenance
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them
Bearing Damage
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them
Permanent Magnets
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them—What is the difference between balance and symmetrical?–what if the you have inbalance magnetic field
Balance, al phases has the same amplitude, and symetrical, al phases are 120°–you will have a lot of vibrations (unbalanced), be carefull because this is caused due to electrical problems and NOT mechanical–maybe a fase was gone
Explain these problems, why does these happens
Harmonics and your sinus will not be PURE any more, result, you have torques that works againt each other. this happens because the grid deliver bad voltages and also when ussing drivers because the PWM are not 100% pure
What are the problems with High Frequencys in the Drivers
It produces high flanks (peaks)–capacitors charges up having a current and reach brakdown levels!!–Bearing Currents
How to solve the problems with High Frequencys in the Drivers–how to minimize the leaking currents
Use of** inverters–Also you can use filters in order to reduce EMC problems–You must groun**d bery perfect.
Shielded cables
- EMC glands
- grounding brackets
- braided earthing tape
Which kind of INDIRECT failures that can have in a Induction motor, and why are interested on them
What are the motor current signatures?
ALways that the current signatures changes we should ask us why?
How do we perform the Motor current signature analysis
First we start with the power analysis
How do we check the power?
Parametrization
What is the spectral analysis?
