The Investigation of Insulation Performance Evaluation of the Large Electrical Rotating Machine in Frequency Domain
DOI:
https://doi.org/10.13052/jmm1550-4646.1544Keywords:
Condition monitoring, Polarization and depolarization current, Complex capacitance, Polarization losses, Frequency domainAbstract
The insulation structure of winding in a large electrical rotating machine consists of epoxy resin and mica material. The insulation structure is composed of many junctions. The insulation problems generate different kinds of signals, such as electromagnetic waves, which may get released from the non-perfect characteristics of the enclosure. This signal may interfere with the functioning of other nearby electronic devices. Therefore, maintaining an excellent condition of the insulation system of the machine is very important. For a condition monitoring of this insulation as proposed in this research, it is taken into consideration the results of the polarization and depolarization current (PDC) measurement of the test sample, and the stator winding rated 13.8 kV was investigated. The experiments were conducted under different thermal stresses, i.e., 25°C (the room temperature) and 100°C (the operation temperature). The test samples were divided into three types: I. haft-overhang, II. overhang and III. full stator bar. From the PDC measurement data record, the complex capacitance and polarization losses (ion migration polarization, slow relaxation polarization and interfacial polarization) were calculated. It was found that the aging of the insulation related to the complex capacitance and polarization losses can be contributed for research in future wireless technology.
Downloads
References
C. Sumereder, R. Woschitz and M. Muhr, “Condition evaluation of generator bars”, International Symposium on Diagnostics for Electric Machine, Power Electronics and Drives, Vienna, Austria, September, 2005
C. Sumereder, R. Woschitz and M. Muhr, “Polarization-depolarization measurements at insulation systems for rotating machines”, International Symposium on Electrical Insulating Materials, Kitakyushu, Japan, June, 2005
Supatra A. Bhumiwat, “On-site non-destructive dielectric response diagnosis of rotating machines”, “IEEE Transaction on Dielectric and Electrical Insulation Volume 17(5), pp. 1453–1460, October, 2010
E. David, G. C. Stone, M. Sasic, “Dielectric response of machine insulation extracted from DC ramp test on individual stator bars”, IEEE Electrical Insulation Conference (EIC), Baltimore, USA, August, 2017
P. G. S. Kumar, K. Kalyan Kumar, “Condition assessment program on aged high voltage insulation of in-service turbine generator”, International Conference on Control Communication and Computing India (ICCC), Trivandrum, India, March, 2016
T. K. Saha, P. Purkait, “Investigation of polarization and depolarization current measurements for the assessment of oil-paper insulation of aged transformers”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 11(1), pp. 144–154, February, 2004
S. Daisy Flora, J. Sundara Rajan,. “Assessment of paper-oil insulation under copper corrosion using polarization and depolarization current measurements”, IEEE Transactions on Dielectrics and Electrical Insulation Volume. 23(3), pp. 1523–1533, August, 2016
Anuradha Kumar and Satish M. Mahajan, “Time domain spectroscopy measurements for the insulation diagnosis of a current transformer”, IEEE Transactions on Dielectrics and Electrical Insulation Volume. 18(5), pp. 1803–1811, October, 2011
Jing Xu and Bo Gao, “Research of aging status assessment of large generator winding insulation by polarization and depolarization current”, IEEE International Conference on High Voltage Engineering and Application (ICHVE), Chengdu, China, September, 2016
E. Sacher, “Dielectric Properties of Polyimide Film. II. DC Properties”, IEEE Transactions on Electrical Insulation Volume EI-14(2), pp. 85–93, April, 1979
Eric David, Reza Soltani and Laurent Lamarre, “PDC measurements to assess machine insulation”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 17(5), pp. 1461–1469, October, 2010
Reza Soltani, Eric David and Laurent Lamarre, “Impact of humidity on dielectric response of rotating machines insulation system” IEEE Transactions on Dielectrics and Electrical Insulation Volume 17(5), pp. 1479–146, October, 2010
T. K. Saha, P. Purkait, “Understanding the impacts of moisture and thermal ageing on transformer’s insulation by dielectric response and molecular weight measurements”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 15(2), pp. 568–582, April, 2008
Reza Soltani, Eric David and Laurent Lamarre, “Impact of humidity on dielectric response of rotating machines insulation system”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 17(5), pp. 1479–1488, October, 2010
Z. Wang, Z. D. Jia, M. H. Fang and Y. S. Li, Z. C. Guan, “Moisture absorption, desorption, and moisture-induced electrical performances of high-temperature vulcanized silicone rubber”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 23(1), pp. 410–417, March, 2016
I. Fofana, H. Hemmatjou and F. Meghnefi, “Effect of thermal transient on the polarization and depolarization current measurements”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 18(2), pp. 513–520, March, 2011
Laurent Lamarre and Eric David, “Temperature dependence of the resistance of modern epoxy mica insulation of HV rotating machines”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 15(5), pp. 1305–1312, October, 2008
E. David, L. Lamarre and D. N. Nguyen, “Measurements of polarization/depolarization currents for modern epoxy-mica bars in different conditions”, Electrical Insulation Conference and Electrical Manufacturing Expo, Nashville, USA, October, 2007
R. Neagu and E. R. Neagu “Analysis of relaxation parameters and their distributions using fractional polarization thermally stimulated discharge currents”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 11(2), pp. 242–248, June, 2004
G. Yianakopoulos, J. Vanderschueren, J. Niezette and A. Thielen, “Influence of physical aging processes on electrical properties of amorphous polymers”, IEEE Transactions on Electrical Insulation Volume 25(4), pp. 693–701, August, 1990
Yasuhiro Matsuda, Yoshihiro Saito and Shigeru Tasaka, “Dipole polarization formed on surface of polypropylene electrets”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 17(4), pp. 1015– 1020, August, 2010
Bjoern Martin, Herbert Kliem, “Non-exponential polarization currents in solid electrolytes”, IEEE Transactions on Dielectrics and Electrical Insulation Volume 22(1), pp. 503–508, February, 2015
Mahdi Shadmand, Hassan Moazami Goudarzi and Sedigheh Kazemi, “PDC characteristics of modern stator insulation systems”, IEEE 11th International Conference on the Properties and Applications of Dielectric Materials (ICPADM), Sydney, Australia, October, 2015