Cogging Torque Minimization Using Skewed and Separated Magnet Geometries

Year 2020, , 223 - 230, 01.03.2020

Adem Dalcalı , Erol Kurt , Emre Çelik , Nihat Öztürk

https://doi.org/10.2339/politeknik.552273

Cited By: 8

Abstract

In the study, analytical design, analysis and
optimization of a 2.5 kW 14-pole, 84-slot permanent magnet synchronous
generator (PMSG) have been performed. The performance characteristics of this
PMSG such as efficiency, torque, cogging torque and magnetic flux density are
assessed. Then, 3D model of the respective generator is acquired to examine the
effect of magnet geometry on the cogging torque produced. In that context, the
effects of splitted and skewed magnet structures are examined. In the first design,
the magnet is modelled with one piece and the rms value of the cogging torque
is found as 436.75 mNm. In the second case, a certain skewed slit is made
alongside the magnet and that yields a slightly reduced cogging torque of
434.58 mNm. In the other design, the magnet of the first design is divided into
two sub-parts, which are then combined together in a skewed fashion. Thus, the
value of cogging torque is found as 159.60 mNm. Eventually, by making two
certain slits on the last model, cogging torque is further depressed down to
89.95mNm. It is concluded from the obtained results that the last design
contributes an improvement in the value of cogging torque up to 80% compared to
the initial design.

Keywords

cogging torque, skewing, PMSG, finite element analysis

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