@inproceedings{HongHyunKangetal., author = {Hong, Jongman and Hyun, Doosoo and Kang, Tae-june and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection and classification of rotor demagnetization and eccentricity faults for PM synchronous motors}, series = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, booktitle = {2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011) : Energy conversion innovation for a clean energy future ; Phoenix, Arizona, USA, 17.-22.09.2011}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4577-0542-7}, issn = {2329-3721}, doi = {10.1109/ECCE.2011.6064103}, pages = {2512 -- 2519}, abstract = {Condition monitoring of rotor problems such as demagnetization and eccentricity in permanent magnet synchronous motors (PMSM) is essential for guaranteeing high motor performance, efficiency, and reliability. However, there are many limitations to the off-line and on-line methods currently used for PMSM rotor quality assessment. In this paper, an inverter-embedded technique for automated detection and classification of PMSM rotor faults is proposed as an alternative. The main concept is to use the inverter to perform a test whenever the motor is stopped, to detect rotor faults independent of operating conditions or load torque oscillations, which is not possible with motor current signature analysis (MCSA). The d-axis is excited with a dc+ac signal, and the variation in the inductance pattern due to the change in the degree of magnetic saturation caused by demagnetization or eccentricity is observed for fault detection. An experimental study on a 7.5kW PMSM verifies that demagnetization and eccentricity can be detected and classified independent of the load with high sensitivity.}, language = {en} } @inproceedings{HongLeeKraletal., author = {Hong, Jongman and Lee, Sang Bin and Kral, Christian and Haumer, Anton}, title = {Detection of airgap eccentricity for permanent magnet synchronous motors based on the d-axis inductance}, series = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, booktitle = {8th IEEE International Symposium on Diagnostics for Electric Machines, Power Electronics \& Drives (SDEMPED), 2011 // 05. - 08.09.2011, Bologna, Italy}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-9301-2}, doi = {10.1109/DEMPED.2011.6063651}, pages = {378 -- 384}, abstract = {The majority of the work performed for detecting eccentricity faults for permanent magnet synchronous motors (PMSM) focus on motor current signature analysis (MCSA), as it provides continuous on-line monitoring with existing current sensors. However, MCSA cannot be applied under nonstationary conditions and cannot distinguish faults with load torque oscillations, which are limitations for many PMSM drive applications. In this paper, it is shown that the d-axis inductance, L d , decreases with increase in the severity of eccentricity due to the change in the degree of magnetic saturation, and it is proposed as a new fault indicator. The inverter can be used to perform a standstill test automatically whenever the motor is stopped, to measure L d for eccentricity testing independent of load variations or oscillations, which is not possible with MCSA. An FE and experimental study on a 10hp PMSM verifies that eccentricity can be detected independent of the load with high sensitivity and reliability.}, language = {en} }