Analysis of Electromagnetic Characteristics of Magnetic Gear with Halbach Arrays and Copper Bar

Abstract

When the coaxial modulated magnetic(CMG) gear is overloaded, the temperature rise of the permanent magnets(PMs) will be aggravated, which leads to a larger loss. To improve the harmonics in the air gap and reduce the losses during overload, a new type magnetic gear model is come up with in this paper. The PMs on the inner rotor adopted Halbach Arrays. Outer rotor yoke and outer PMs slotted and add a copper bar. The magnetic field of CMG under overload is studied and the reason of the demagnetization of PMs on the rotor is discussed. The finite element analysis(FEA) is used to compare air gap magnetic density, output torque, and loss of two models. The proposed magnetic gear not only improves the air gap magnetic density and weakens the unworked harmonics, but also increases the output torque, reduces the eddy current loss and the iron loss.