Fractional Slot Concentrated Windings: A New Method to Manage the Mutual Inductance between Phases in Three-Phase Electrical Machines and Multi-Star Electrical Machines

Machines

Bellemain Napame¹  Olivier Barre² 

[1] AREVA NP, 27 rue de l'Industrie BP 20189, Jeumont Cedex 59573, France;Rectorat de Lille, Clg DESCARTES, 2 rue Lavoisier, Mons-En-Baroeul 59370, France;

关键词: fractional slot concentrated windings (FSCW);    multi-star winding;    multi-phase windings;    mutual inductance effect mitigation;    surface-mounted permanent magnets machines (SPM);   

DOI  :  10.3390/machines3020123

来源: DOAJ

【 摘 要 】

Mutual inductance is a phenomenon caused by the circulation of the magnetic flux in the core of an electrical machine. It is the result of the effect of the current flowing in one phase on the other phases. In conventional three-phase machines, such an effect has no influence on the electrical behaviour of the device. Although these machines are powered by power inverters, no problem should occur. The result is not the same for multi-star machines. If these machines are using a conventional winding structure, namely distributed windings, and are powered by voltage source converters, current ripples appear in the power supply lines. These current ripples are related to magnetic couplings between the stars. Designers should check these current ripples in order to stay within the limits imposed by the specifications. These electric current disturbances also provide torque ripples. With concentrated windings, a new degree of freedom appears; the configuration—number of slots/number of poles—can have a positive impact. The circulation of the magnetic flux is the initial phenomenon that produces the mutual inductance. The main goal of this discussion is to describe a design method that is able to produce not only a machine with low mutual inductance between phases, but also a multi-star machine where the stars and the phases are magnetically decoupled or less coupled. This discussion only takes intoaccount the machines that use permanent magnets mounted on the rotor surface. Thisarticle is part of a study aimed at designing a high efficiency generator using fractional-slotconcentrated-windings (FSCW).

【 授权许可】

Unknown