EARLY DETECTION OF ROTOR CORE BREAKAGE BASED ON PHASE CURRENT HARMONICS IN LOW-POWER ASYNCHRONOUS MOTORS (MCSA)

In this article, the problem of early detection of rotor rod breakage (Broken Rotor Bar, BRB) in low-power asynchronous motors (0.37-15 kW) is considered. The research is based on the Motor Current Signature Analysis (MCSA) - a diagnostic approach based on the stator phase current spectrum. The results of operational monitoring conducted in 2022-2025 showed an increase in the number of suspicious BRB cases from 2.0 to 5.3 per 100 motor bases, which confirms the relevance of this defect. Spectral analysis revealed the stable appearance of side-band components around the network frequency in the presence of BRB, whereas in a healthy state these components are not significantly observed. The study proposed a monitoring concept based on a portable current sensor (Hall/CT) and the MCSA algorithm. This approach allows for the early detection and organization of continuous monitoring in real operation, even under conditions of noise and variable load, characteristic of low-power engines.