Uszkodzenia łożysk w silnikach indukcyjnych użytych w organach urabiających kombajnów górniczych

The paper presents research results dealing with bearing faults of high power induction motors.In the chapter 2 are presented simulation results, as an introduction to laboratory measurements. The harmonic analysis of the stator winding phase currents are shown In charter 3. In charter 4 are presented the causes of bearing currents forming during motor direct startup. The figure 3 shows the graphical presentation of the bearing currents forming issue. In charter 5 measurement results are discussed. Waveforms of shaft currents and voltages, and their Fourier transforms are shown in Fig. 5, 6 and 7. Equivalent circuit diagram for bearing current flow is presented in chapter 6, Fig. 9. Equivalent circuit diagram for bearing current flow is presented in chapter 6, Fig. 9. Conclusions drawn from laboratory researches are presented in chapter 8.