Robust on line stator turn fault identification system

A system for determining turn faults in an induction motor, comprising:

• a device coupled to the induction motor and configured to determine a negative sequence voltage, a negative sequence current and a positive sequence current, the device comprising a memory;
• wherein the memory comprises instructions for:
• determining a normalized cross-coupled impedance, wherein the normalized cross-coupled impedance comprises a differential impedance normalized by the negative sequence impedance;
• and
• determining the normalized cross-coupled impedance indicates the presence of a turn fault.

A method for determining turn faults in an induction motor, comprising:

• determining a negative sequence voltage;
• determining a negative sequence current and a positive sequence voltage;
• determining a negative sequence impedance;
• determining a normalized cross-coupled impedance from the negative sequence voltage, negative sequence current, positive sequence positive, and negative sequence impedance;
• and
• determining whether the normalized cross-coupled impedance indicates the presence of a turn fault.

A method for determining turn faults in an induction motor, comprising:

• determining a normalized cross-coupled impedance;
• comparing the normalized cross-coupled impedance to a first threshold;
• and
• if the normalized cross-coupled impedance is greater than the first threshold, triggering a first alarm.