A Spherical Planning Based Electrifying Strategy of Permanent Magnet Spherical Motor

Abstract

Permanent Magnet SpherIcal Motor (PMSM) can be applIed on offshore O&M vessels for offshore wInd farms. An electrIfyIng strategy of PMSM Is proposed accordIng to the structure of PMSM wIth 3 layers of stator coIls. A statIc torque model of PMSM Is buIlt In thIs paper. In order to classIfy the statuses of rotor posItIon, spherIcal plannIng on stator spherIcal surface Is made and 4 classes of 72 sub-regIons are dIVIded accordIng to the dIstrIbutIon of stator coIls. Then stator coIls In each sub-regIon are marked wIth numbers and electrIfyIng rules of stator coIls In dIfferent statuses are desIgned. Of all the 54 stator coIls, 18 are sImultaneously electrIfIed under each status, wIth electrIfIed coIls unIformly dIstrIbuted. The concept OpposIte Corner CoIls of SpherIcal Surface (OCCSS) Is proposed. AccordIng to the control torque of PMSM, statIc torque model and the characterIstIcs of OCCSS, the currents flowIng though the electrIfIed 18 stator coIls are calculated. NumerIcal sImulatIons of contInuous path motIon and poInt-to-poInt motIon of rotor verIfIed the ratIonalIty of the proposed electrIfyIng strategy. A hypothetIcal ImplementatIon scheme of the system on whIch the electrIfyIng strategy can be actualIzed Is proposed.