Portable acquisition and identification tool for induction machine diagnosis

A new parameters identification method for induction machine electrical faults detection is presented in this paper. Typical evolutive faults like: phase resistance increase caused by poor contacts, turn-to-turn short circuits, unbalanced supply voltages, magnetic circuit ageing and squirrel-cage bar rupture, are taken into consideration. A triphase abc frame it was taken in to consideration for real phase parameters identification. In order to provide the electrical parameters, an identification technique based on currents, voltages and speed acquisition during transients (e.g. starting-up) has been developed on a portable acquisition and post-processing system. The proposed equipment includes: 486 notebook with PCMCIA acquisition board, current clampmeters, voltages probes and signal conditioning module and can be applied to any drive without interfering with operating conditions. Also, a data base software processor was developed for storing and comparison against the reference set of each new parameter set identification, enabling a time evolution behaving. The system can be successfully applied for both periodical preventive maintenance and electrical parameters verification of repaired induction machines.