Rotor bar breakage data obtained from fatigue test

Abstract

The data hereby provided was acquired during a fatigue test developed at the Department of Electrical Engineering, Universitat Politecnica de Valencia (Universidad Politecnica de Valencia, Spain) in 2011 by PhD student Vicente Climente-Alarcon under supervision of Prof. Martin Riera-Guasp. The fatigue test involved subjecting a 1.5 kW, 1 pole pair induction motor to severe cycling until a bar breakage naturally developed. The cycling consisted of a Direct-on-line (DOL) startup followed by a stationary operation period of at least 10 seconds. A plug stopping was added at the later stages of the test. To maximize the possible damage to the rotor cage, a high load inertia caused heavy (long) startup and stopping transients. ******* Epochs ******* Since the bar breakage did not develop naturally, the rotor cage was successively weakened, defining three stages in the fatigue test: original rotor, lathed rotor and weakened bar. The data shared here corresponds only to roughly the last one, beginning at cycle 79008, in which the end of one bar was narrowed by boring holes in its connection to the end ring. Some previous cycles (79000 to 79007) are also shared. All the details about the fatigue test can be found (in Spanish) in: Climente Alarcon, V. (2012). Aportacion al mantenimiento predictivo de motores de induccion mediante modernas tecnicas de analisis de la senal. Universitat Politecnica de Valencia. doi:10.4995/Thesis/10251/15915. The state of the rotor during the provided cycles is as follows: Cycles State 79000-79007 Lathed 79008-79112 Lathed and one 3 mm diameter hole 79113-80187 Lathed and two 3 mm diameter holes 80188-80404 Lathed and two 3 mm diameter holes (current sensors changed) 80405-80857 Lathed and two 4 mm diameter holes 80858-81215 Lathed, one 4 mm and one 4.5 mm diameter holes. Bar completely broken @ 81071 81216-81653 Bar broken 81654-81882 Broken bar rests removed 81883-82265 Bar cut also at the other end ******* Data ******* The data provided here only contains the current waveform in phase C excluding the plug stopping, ambient temperature at the beginning of the cycle, motor temperature at the beginning of the cycle and maximum motor temperature during the provided data cycle (which coincides with the motor temperature at the end of the stationary period). Stationary rotational speed, as captured by an encoder, is also included. For an easier handling, all these magnitudes are stored in a single column in each file, for instance: Contents of file 81571.txt 81571 -> Cycle number, must coincide with the name of the file 26.6 -> Ambient temperature at the beginning of the cycle in oC 78.2 -> Motor temperature at the beginning of the cycle in oC 85.3 -> Motor temperature at the end of the recorded period in oC 48.0 -> Rotational speed during the stationary period in Hz 0.000000 -> Beginning of the current waveform in phase C in A 0.002083 0.000000 -0.002083 0.004167 0.004167 0.002083 · · The current waveform is sampled at 5 kSamples/second and it spans around 20 seconds, of which at least 10 correspond to stationary operation. Different sensors were used during the fatigue test, and hence the precision of the current measurements may vary in the provided data. However, the cycles 80188-82265, including the bar breakage itself, were captured using the same sensors and configuration. The motor temperature corresponds to the value measured inside the connection box on the stator yoke. ******* Publications ******* Further details can be found in the publications where data from the fatigue test have been analyzed: V. Climente-Alarcon, J. A. Antonino-Daviu, E. Strangas, M. Riera-Guasp, “Bar breakage mechanism and prognosis in an induction motor,” in Proc. SDEMPED, Valencia, Spain, 2013, pp. 538–545, doi: 10.1109/DEMPED.2013.6645775 V. Climente-Alarcon, J. A. Antonino-Daviu, A. Haavisto, A. Arkkio, “Evolution of high order fault harmonics during a bar breakage with compensation,” presented at the International Conf. Electrical Machines ICEM, Berlin, Germany, Sep. 2–5, 2014, doi: 10.1109/ICELMACH.2014.6960441 V. Climente-Alarcon, J. A. Antonino-Daviu, E.G. Strangas, M. Riera-Guasp, “Rotor-bar breakage mechanism and prognosis in an induction motor,” IEEE Trans. Ind. Electron., vol. 62, no. 3, Mar. 2015, pp. 1814-1825, doi: 10.1109/TIE.2014.2336604 V. Climente-Alarcon, D. Nair, R. Sundaria, J. A. Antonino-Daviu, Antero Arkkio, “Combined Model for Simulating the Effect of Transients on a Damaged Rotor Cage,” IEEE Trans. Ind. Appl., vol. 53, no. 4, Jul.-Aug. 2017, pp. 3528-3537, doi: 10.1109/TIA.2017.2691001 V. Climente-Alarcon, A. Arkkio, J. Antonino-Daviu, “Study of thermal stresses developed during a fatigue test on an electrical motor rotor cage,” International Journal of Fatigue, vol. 120, Mar. 2019, pp. 56-64, doi: 10.1016/j.ijfatigue.2018.11.003