Investigation of a less rare-earth permanent-magnet machine with the consequent pole rotor

Abstract

Minimization of torque ripple in ferrite-assisted synchronous reluctance motors by using asymmetric stator AIP Advances 8, 056606 (2018) Due to the rising price of rare-earth materials, permanent-magnet (PM) machines in different applications have a trend of reducing the use of rare-earth materials. Since iron-core poles replace half of PM poles in the consequent pole (CP) rotor, the PM machine with CP rotor can be a promising candidate for less rare-earth PM machine. Additionally, the investigation of CP rotor in special electrical machines, like hybrid excitation permanent-magnet PM machine, bearingless motor, etc., has verified the application feasibility of CP rotor. Therefore, this paper focuses on design and performance of PM machines when traditional PM machine uses the CP rotor. In the CP rotor, all the PMs are of the same polarity and they are inserted into the rotor core. Since the fundamental PM flux density depends on the ratio of PM pole to iron-core pole, the combination rule between them is investigated by analytical and finite-element methods. On this basis, to comprehensively analyze and evaluate PM machine with CP rotor, four typical schemes, i.e., integerslot machines with CP rotor and surface-mounted PM (SPM) rotor, fractional-slot machines with CP rotor and SPM rotor, are designed to investigate the performance of PM machine with CP rotor, including electromagnetic performance, antidemagnetization capacity and cost. © 2017 Author (s)

Variable reluctance synchronous machines in saturated mode

“…A linear part that corresponds to the linear mode. A non-linear part that corresponds to the sattured mode [15], [16].…”

“…The motor's phase inductances are expressed by the ( 14) instead from ( 15) and (16). These ( 14) to (16) show all the studied parameters and gives the mathematical relationship.…”

Design Modifications for Improving Modulation Flux Capability of Consequent-Pole Vernier-PM Machine in Comparison to Conventional Vernier-PM Machines

“…This electric machine topology is gained considerable research interest recently. Recently, the consequent-pole PM machines are introduced and investigated to improve the efficient use of PM materials [6]. The Consequent-Pole VPM (CP-VPM) is a special topology of VPM machines, which requires much lower volume of PM materials than the Conventional VPM (CVPM) structure with the same torque density.…”