Synchronous reluctance motor technology: industrial opportunities, challenges and future direction

Abstract

The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Abstract: In recent years, the desire for high efficiency and high torque density electric motors without permanent magnet materials for the industrial, as well as the specialist product sectors, has increased significantly and has developed into hot research topic. This paper discusses a reemergent type of AC electrical machine, the Synchronous Reluctance Machine. Current EU legislation aims to tackle global energy usage and reduce greenhouse gas emissions, the Synchronous Reluctance motor is discussed in this context -Its potential to become the future industry standard for high efficiency, low cost, high output industrial drives for fan, pump and mill type industrial applications is explored. The reader will be brought up to speed with Synchronous Reluctance technology, presented with both its advantages and disadvantages with the suitability of the technology for industry application being discussed and a comparison made with respect to competing technologies -the traditional induction machine and the modern permanent magnet machine. Current and future research trends are outlined and a simple engineering case study is also presented as an indication of the energy saving potential of this type of machine. This paper aims to inform students, engineers and key-decision makers in industry about this exciting technology.

On the Influence of Increased Stator Leakage Inductance in Single-Tooth Wound Synchronous Reluctance Motors

“…The torque ripple was analyzed in [14] and found to be due to a 2 nd order counter-rotating 8 pole field interacting with the rotor harmonic saliency, causing significant torque oscillation. The motor has of 6 slots, constructed form a segmented stator core arrangement where the coils are pre-wound onto each segment before assembly [18]. The transversely laminated rotor consists of 4 rotor poles with optimized flux barrier design.…”

“…The machine was first described and analysed in [14], with further analysis in [4] and experimental validation in [5,18] the proposed motors performance was experimentally verified both statically (magnetic circuit characterisation) and dynamically on a dynamometer test rig. Figure 6 shows the prototyped rotor in detail.…”

Optimised Design of Permanent Magnet Assisted Synchronous Reluctance Machines for Household Appliances

“…The continuous increase of electrical energy demand compels a significant effort in the direction of reducing environment pollution and greenhouse gases [1]. Therefore, the efficiency improvement of electric motors and drives, adopted in many application fields, is of paramount importance [2].…”

“…Super-Premium/IE4 and Ultra-premium/IE5 efficiency classes are to be defined in the 2nd Edition of the IEC3 60034-30 standard. For line-start fixed-speed applications, Super-Premium/IE4class line-start permanent magnet (PM) motors and squirrelcage induction motors are recent entrances in the industrial motor market [1]. For variable-speed applications, IE4-class synchronous reluctance motors are also a recent entrance in the market.…”

“…SynRel machines with ferrite injection have also been presented for washing machine applications in different research works [10], [20], highlighting higher efficiency and relatively cheap price, with respect to SCIMs. The use of ferrite magnets is not significantly affecting the cost of the motor because of the low material price, about 3.28 $/kg [1].…”