Patent ID: 8401822

Claim:
A system for determining wellness of a three-phase rotating electrical apparatus having a rated current, said system comprising: a three-phase electrical switching, control, protection or monitoring apparatus operatively associated with the three-phase rotating electrical apparatus and being structured to provide name plate data, three-phase RMS current, three-phase RMS voltage, percent load, estimated current rotating coordinate system vectors, estimated voltage rotating coordinate system vectors, frequency, and user fault settings thereof; and a wellness circuit for the three-phase rotating electrical apparatus, said wellness circuit being separate from the three-phase electrical switching, control, protection or monitoring apparatus, said wellness circuit comprising: a current sensor scaled to the rated current and structured to provide a notch current signal representative of one current of three phases of current flowing through said three-phase electrical switching, control, protection or monitoring apparatus, an interface to the three-phase electrical switching, control, protection or monitoring apparatus, said interface receiving from the three-phase electrical switching, control, protection or monitoring apparatus the name plate data, the three-phase RMS current, the three-phase RMS voltage, the percent load, the estimated current rotating coordinate system vectors, the estimated voltage rotating coordinate system vectors, the frequency, and the user fault settings, and a processor employing the name plate data, the three-phase RMS current, the three-phase RMS voltage, the percent load, the estimated current rotating coordinate system vectors, the estimated voltage rotating coordinate system vectors, the frequency, and the user fault settings and the notch current signal to determine wellness of the three-phase rotating electrical apparatus, wherein external interfaces of the wellness circuit are limited to the current sensor and the interface to the three-phase electrical switching, control, protection or monitoring apparatus.