Cogging torque sensitivity to permanent magnet tolerance combinations

• Autorzy: Gašparin L. , Fišer R.
• Języki publikacji: EN

Abstrakty

EN

This study presents the dependence of the level and harmonic structure of the cogging torque in permanent magnet synchronous motors (PMSM) to imperfections of permanent magnet (PM) dimensions and positions, which can not be avoided in massproduction. Slightly diverse dimensions and misplacements of PMs are introducing asymmetries in magnetic field distribution which cause additional harmonic components. A finite element method (FEM) and Fast Fourier transform (FFT) were used to calculate cogging torque harmonic components with regard to several combinations of PM assembly imperfections. It has been established and proved that unequal PMs cause magnetic asymmetries which give rise to additional cogging torque harmonic components and consequently increase the total cogging torque. It is also shown that in some particular combinations the influence of an individual PM imprecision could compensate with others due to different phase shifts which can result even in the decrease of cogging torque. Considering presented results it is possible to foresee which additional harmonic components will comprise the cogging torque of mass-produced PMSMs due to PM imperfections. In this way the designers are able to predetermine required manufacturing tolerances to keep the level of cogging torque in a admissible level. Simulation results were verified and confirmed by laboratory tests.

Słowa kluczowe

EN

cogging torque; finite element method; harmonic components; PM synchronous motor

• Wydawca: Polish Academy of Sciences, Committee on Electrical Engineering
• Czasopismo: Archives of Electrical Engineering
• Rocznik: 2013
• Tom: Vol. 62, nr 3
• Strony: 449--461
• Opis fizyczny: Bibliogr. 19 poz., rys., tab.

Twórcy

autor

Gašparin L.

• Letrika d.d., Polje 15, 5290 Šempeter pri Gorici, Slovenia

autor

Fišer R.

• Faculty of Electrical Engineering, University of Ljubljana Tržaška cesta 25, 1000 Ljubljana, Slovenia

Bibliografia

• [1] Gieras J.F., Permanent-Magnet Motor Technology - Design and Applications. CRC Press, 3rd edn. (2010).
• [2] Krishnan R., Permanent Magnet Synchronous and Brushless DC Motor Drives. CRC Press (2010).
• [3] Bianchi N., Bolognani S., Design techniques for reducing the cogging torque in surface-mountedPM motors. IEEE Transaction on Industry Application 38(5): 1259-1265 (2002).
• [4] Islam R., Husain I., Fardoun A., McLaughlin K., Permanent-magnet synchronous motor magnet designswith skewing for torque ripple and cogging torque reduction. IEEE Transactions on Industry Applications 45(1): 152-160 (2009).
• [5] Islam M.S., Mir S., Sebastian T., Issues in reducing the cogging torque of mass-produced permanentmagnet brushless DC motors. IEEE Transaction on Industry Application 40(3): 813-820 (2004).
• [6] Gašparin L., Černigoj A., Markič S., Fišer R., Additional cogging torque components in permanentmagnet motors due to manufacturing imperfections. IEEE Transactions on Magnetics 45(3): 1210-1213 (2009).
• [7] Miljavec D., Zidarič B., Eddy current losses in permanent magnets of the BLDC machine. Compel 26(4): 1095-1104 (2007).
• [8] Černigoj A., Gašparin L., Fišer R., Native and additional cogging torque components of PM synchronousmotors - evaluation and reduction. Automatika 51(2): 157-165 (2010).
• [9] Lateb R., Takorabet N., Meibody-Tabar F., Enon J., Sarribouete A., Design technique for reducingthe cogging torque in large surface mounted magnet motors. Proc. 16th ICEM (CD), Poland, Kraków, 1-6 (2004).
• [10] Zhu Z.Q., Ruangsinchaiwanich S., Chen Y., Howe D., Evaluation of superposition technique forcalculating cogging torque in permanent-magnet brushless machines. IEEE Transactions on Magnetics 42(5): 1597-1603 (2006).
• [11] Nemec M., Drobnič K., Nedeljković D., Ambrožič V., Direct current control of a synchronous machinein field coordinates, IEEE Trans. Industrial Electronics. 56(10): 4052-4061 (2009).
• [12] Gašparin L., Černigoj A., Fišer R., Phenomena of additional cogging torque components influencedby stator lamination stacking methods in PM motors. Compel 28(3): 682-690 (2009).
• [13] Coenen I., Gracia M.H., Hameyer K., Influence and evaluation of non-ideal manufacturing processon the cogging torque of a permanent magnet excited synchronous machine. Compel 30(3): 876-884 (2011).
• [14] Heins G., Brown T., Thiele M., Statistical analysis of the effect of magnet placement on coggingtorque in fractional pitch permanent magnet motors. IEEE Transactions on Magnetics 47(8): 2142-2148 (2011).
• [15] Gašparin, L., Černigoj, A. and Fišer R., Additional cogging torque components due to asymmetry instator back iron of PM synchronous motors, Compel, 30(3): 894-905, (2011).
• [16] Coenen I., van der Giet M., Hameyer K, Manufacturing tolerances: estimation and prediction ofcogging torque influenced by magnetization faults. IEEE Transactions on Magnetics 48(5): 1932-1936 (2012).
• [17] Bianchinni C., Immovilli F. Lorenzani E., Bellini A., Davoli M, Review of design solutions forinternal permanent-magnet machines cogging torque reduction. IEEE Transactions on Magnetics 48(10): 2685-2693 (2012).
• [18] Azar Z., Zhu Z.Q., Ombach G., Investigation of torque-speed characteristics and cogging torque offractional-slot IPM brushless AC machines having alternate slot openings. IEEE Transactions on Industry Applications 48(3): 903-912 (2012).
• [19] Wang D., Wang X., Qiao D., Pei Y., Jung S., Reducing cogging torque in surface-mounted permanent-magnet motors by nonuniform distributed teeth method. IEEE Transactions on Magnetics 47(9): 2231-2239 (2011).