Investigation Into Loss Reduced Rotor Slot Structure by Analyzing Local Behaviors of Harmonic Magnetic Fluxes in Inverter-Fed Induction Motor

Case Study: Variable-Voltage DC Bus With Energy Recovery System for Industrial Plants

“…To increase efficiency in motor drives and related systems is of primary importance because 40% of the electric energy generated worldwide is consumed by electric motors in industry [39], [40]. In this context replacement of induction motors (IMs) by permanent magnet synchronous motors (PMSMs) were presented by [41], [42]. With the significant advances in power electronics, the amount of PMSMs driven by inverters has increased significantly, mainly because the cost associated with the drives has become competitive with equivalent three-phase IM drivers as shown in Fig.…”

Design of a high speed 18/12 switched reluctance motor drive with an asymmetrical bridge converter for electric vehicles

“…Equivalent circuit of one phase of SRM price of the rare earth magnets and the flux weakening capability to apply negative current which originates huge copper and iron losses and in reality contribute to increase the flux harmonics in the machine [21]. The induction motor also has extraordinary flux saturation and high operational frequency therefore the secondary winding losses are considerably greater than typical values and huge eddy current losses are generated, hence the conventional induction motor is not good enough to be used for EV application as stated in literature [22][23][24][25].…”

Optimization and Improvement of Advanced Nonoverlapping Induction Machines for EVs/HEVs

“…For further performance improvement, some geometric design parameters may be changed. Because of slotting and saturation effects, winding MMF and slip harmonics, the IMs contain high-order frequency components in the air-gap, particularly at the stator tooth tip parts and dominantly at the rotor tooth tip parts [27]- [31]. Because of substantial bar copper loss and subsequent overheating owing to air-gap flux density harmonics, the conventional rotor structure design with an open-slot cast rotor (OS) is not a good candidate for adoption in the EV/HEV applications [31]- [34].…”

“…It was hypothesized in [38] that by switching from a circular-bar design to a dropshape bar design, the power density may be enhanced. An unconventional rotor configuration with un-even toot tips and narrower slot openings has been developed in [31] to simultaneously minimize time and space harmonics. Furthermore, many studies have focused on the best rotor slot design for improved torque and starting characteristics, such as line-start conditions, rotor bar losses, and evaluating alternative rotor slot designs [38], [39], [44].…”