TY - GEN
T1 - In-service monitoring of stator slot magnetic wedge condition for induction motors
AU - Han, Sangwoo
AU - Jung, Junyeong
AU - Lee, Kun Wang
AU - Lee, Sang Bin
AU - Nandi, Subhasis
AU - Kim, Byunghwan
AU - Kang, Byunghee
N1 - Funding Information:
This work was supported in part by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (NRF-2013R1A1A 2010370) and in part by the Human Resources Development program (20134030200340) of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Trade, Industry and Energy.
PY - 2015/10/27
Y1 - 2015/10/27
N2 - Stator slot magnetic wedges are used instead of conventional epoxy glass wedges in large, high output induction motors since the motor efficiency and power factor can be improved. However, cases of loose or missing magnetic wedges due to their weak mechanical strength have recently been increasingly reported. Although missing wedges can deteriorate motor performance and reliability, there currently is no test method accepted in the field for wedge quality assessment other than off-line, disassembled visual inspection. In this paper, a new in-service method for monitoring the magnetic wedge condition in induction motors based on the negative sequence information is proposed. The new method is developed based on the analysis of the dynamic model of the induction motor with missing magnetic slot wedges, derived in this paper. The proposed method is verified experimentally on a 380 V, 5.5 kW induction motor with custom-built magnetic wedges, and on a finite element model of a 6.6 kV, 1850 kW induction motor. It is shown that the proposed method can provide on-line detection of missing magnetic wedges, which can help reduce maintenance costs and risk of degradation in motor performance.
AB - Stator slot magnetic wedges are used instead of conventional epoxy glass wedges in large, high output induction motors since the motor efficiency and power factor can be improved. However, cases of loose or missing magnetic wedges due to their weak mechanical strength have recently been increasingly reported. Although missing wedges can deteriorate motor performance and reliability, there currently is no test method accepted in the field for wedge quality assessment other than off-line, disassembled visual inspection. In this paper, a new in-service method for monitoring the magnetic wedge condition in induction motors based on the negative sequence information is proposed. The new method is developed based on the analysis of the dynamic model of the induction motor with missing magnetic slot wedges, derived in this paper. The proposed method is verified experimentally on a 380 V, 5.5 kW induction motor with custom-built magnetic wedges, and on a finite element model of a 6.6 kV, 1850 kW induction motor. It is shown that the proposed method can provide on-line detection of missing magnetic wedges, which can help reduce maintenance costs and risk of degradation in motor performance.
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U2 - 10.1109/ECCE.2015.7310633
DO - 10.1109/ECCE.2015.7310633
M3 - Conference contribution
AN - SCOPUS:84963604796
T3 - 2015 IEEE Energy Conversion Congress and Exposition, ECCE 2015
SP - 6948
EP - 6955
BT - 2015 IEEE Energy Conversion Congress and Exposition, ECCE 2015
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 7th Annual IEEE Energy Conversion Congress and Exposition, ECCE 2015
Y2 - 20 September 2015 through 24 September 2015
ER -