Abstract ：The doubly skewed rotor induction motor is a novel type of motor to improve the performance of ordinary skewed rotor induction motors. However, the effects of the inter-bar currents and axial variations in saturation on its starting performance have not been fully studied. In order to accurately calculate the starting torque, based on three-dimensional finite element transient field, a model considering inter-bar currents and axial variations in saturation was established. An equivalent circuit parameter method considering the variations in main leakage reactance was proposed to calculate the starting torque performance of doubly skewed rotor induction motor. Meanwhile, the air-gap magnetic flux density was studied to explain that three-dimensional finite element models can take into account the axial variations in saturation. The relationship between inter-bar resistance and torque-speed curve was investigated by simulating the finite element models of different inter-bar resistances. The calculated results were compared with the results of the virtual displacement method and the measurements, which indicated that the proposed method can accurately calculate the starting torque performance.
Bao Xiaohua,Fang Jinlong,Xu Wei等. Starting Torque Analysis of Doubly Skewed Rotor Induction Motor Considering Inter-Bar Currents and Axial Variations in Saturation[J]. Transactions of China Electrotechnical Society, 2019, 34(4): 646-653.
[1] Dorrell D G, Holik P J, Rasmussen C B.Analysis and effects of inter-bar current and skew on a long skewed- rotor induction motor for pump applications[J]. IEEE Transactions on Magnetics, 2007, 43(6): 2534-2536. [2] Wang Lang, Bao Xiaohua, Di Chong, et al.Influence on vibration and noise of squirrel-cage induction machine with double skewed rotor for different slot combinations[J]. IEEE Transactions on Magnetics, 2016, 52(7): 1-4. [3] 鲍晓华, 狄冲, 汪朗. 笼型感应电机转子斜槽研究综述及展望[J]. 电工技术学报, 2016, 31(6): 1-12. Bao Xiaohua, Di Chong, Wang Lang.Review and prospect of skewed rotor in squirrel cage induction machines[J]. Transactions of China Electrotechnical Society, 2016, 31(6): 1-12. [4] Ahn H, Jang G, Chang J, et al.Reduction of the torque ripple and magnetic force of a rotatory two-phase transverse flux machine using herringbone teeth[J]. IEEE Transactions on Magnetics, 2008, 44(11): 4066-4069. [5] Wang Lang, Bao Xiaohua, Di Chong, et al.Effects of novel skewed rotor in squirrel-cage induction motor on electromagnetic force[J]. IEEE Transactions on Magnetics, 2015, 51(11): 1-4. [6] 江建中, 傅为农. 斜槽异步电动机的多截面有限元法分析[J]. 电工技术学报, 1997, 12(5): 11-16. Jiang Jianzhong, Fui Weinong.Multi slice finite element analysis of skewed induction motors[J]. Transactions of China Electrotechnical Society, 1997, 12(5): 11-16. [7] Gersh D, Smith A C, Samuelson A.Measurement of inter-bar resistance in cage rotors[C]//1997 IET Eighth International Conference on Electrical Machines and Drives, Cambridge, UK, 1997: 253-257. [8] Dorrell D G, Miller T J E, Rasmussen C B. Inter-bar currents in induction machines[J]. IEEE Transactions on Industry Applications, 2003, 39(3): 677-684. [9] Carlson R, Silver C A D, Safowski N, et al. Analysis of the effect of inter-bar currents on the performance of polyphase cage-induction motors[J]. IEEE Industry Applications Society, 2003, 39(6): 1674-1680. [10] Williamson S, Mcclay C I.The effect of axial variations in saturation due to skew on induction motor equivalent-circuit parameters[J]. IEEE Transa- ctions on Industry Applications, 1999, 1(6): 1323-1331. [11] Dorrell D G, Holik P J, Thougaard H J, et al.Modelling axial variations in induction motors with rotor skew using multi-sliced 2D finite element analysis[C]//2006 3rd IET International Conference on Power Electronics, Machines and Drives, Dublin, Ireland, 2007: 686-690. [12] Güdelhofer J, Gottkehaskamp R, Möckel A.3D FEM approach to study the physics of inter-bar currents in induction machines[C]//IEEE XXII International Con- ference on Electrical Machines, Lausanne, Switzerland, 2016: 18-24. [13] Boglietti A, Cavagnino A, Lazzari M.Computational algorithms for induction motor equivalent circuit parameter determination-Part II: skin effect and magnetizing characteristics[J]. IEEE Transactions on Industrial Electronics, 2011, 58(9): 3734-3740. [14] 凌在汛, 周理兵, 张毅, 等. 屏蔽感应电机等效电路参数的有限元计算法[J]. 电工技术学报, 2016, 31(22): 28-34. Ling Zaixun, Zhou Libing, Zhang Yi, et al.Para- meters calculation of canned solid-rotor induction motor by finite element analysis[J]. Transactions of China Electrotechnical Society, 2016, 31(22): 28-34. [15] Jangho Y, Sang B L.Simplified approach for predicting the starting performance of induction machines based on rotor design modification[J]. IEEE Transactions on Magnetics, 2017, 53(6): 1-4. [16] 梁文毅, 陆天雄, 张翔. 基于分段斜槽技术的电机斜槽特性分析[J]. 电工技术学报, 2011, 26(11): 135-140. Liang Wenyi, Lu Tianxiong, Zhang Xiang.Skew effect simulation based on multi-slices model[J]. Transactions of China Electrotechnical Society, 2011, 26(11): 135-140. [17] Liang X, Ilochonwu O.Induction motor starting in practical industrial applications[J]. IEEE Transa- ctions on Industry Applications, 2010, 47(1): 271-280. [18] 梁艳萍, 张广超, 高莲莲, 等. 核主泵驱动电动机屏蔽套涡流损耗混合算法研究[J]. 电工技术学报, 2018, 33(5): 1015-1023. Liang Yanping, Zhang Guangchao, Gao Lianlian, et al.Research on hybrid algorithm of can losses in double canned induction motor for nuclear pump[J]. Transactions of China Electrotechnical Society, 2018, 33(5): 1015-1023.
2019, Vol. 34 
