Design of synchronous reluctance machines with a wide speed range

Yılmaz, Yusuf Basri
Synchronous reluctance machines (SynRMs) are a good alternative for traction and industrial applications due to their good power density, low cost and high efficiency. However, they suffer from high torque ripple, low power factor and poor high speed performance due to their singly excited nature. To overcome these challenges, rotor geometries are optimized to get a low torque ripple and ferrite magnets are inserted in the flux barriers to get a higher power factor and a better high speed performance. This thesis aims to propose a methodology to design synchronous reluctance machine with a wide speed range with high power output by using parametric sweep and optimization methods. It is observed that rotor design has an effect on the high-speed performance of SynRMs. However, even the maximum power of the optimized machine decreases sharply as the field weakening region of the machine is extended. Moreover, when the high speed performance of a SynRM is concerned, mechanical and electromagnetic designs must be performed concurrently. To assure a mechanically robust rotor structure, radial ribs must be added to the flux barriers but these connections cause a decrease in the electromagnetic performance of the machine. So, the high speed performance of the machine decreases further as the ribs in the flux barriers must get thicker as the maximum speed is increased. Based on these findings, it is concluded that PM assistance is required to reach an acceptable high speed performance. Therefore, the amount of required PM material to reach a satisfactory output power at the maximum speed is determined for selected SynRM designs. These analysis is performed with both ferrite and NdFeB type permanent magnet materials, and ferrite assisted SynRM design is found to be favorable due to its much lower cost. Finally, the design and analysis methods are validated with the measurements taken from a small-scaled prototype SynRM that is designed in this study.


Optimal design of synchronous reluctance machines
Kiani, Morgan; Bostancı, Emine; Fahimi, Babak (2017-12-15)
Electric machines are optimized to the extent of their magnetic configuration and manufacturability. Thanks to recent advances in development of composite material (SMC), 3-D printing, and programmable magnets, manufacturing capabilities have changed dramatically. Introducing of cloud computing and impressive computational resources has opened new opportunities in virtual prototyping in a multi-physics environment. These enabling technologies present a potential for a transformative approach in optimal desi...
Simulation of Dynamic Operation in Salient Pole Synchronous Machines
Dordea, Toma; Munteanu, Radu; Campeanu, Aurel (2011-09-10)
The design of today's high performance synchronous motors must take into account not only the steady state but also practically inevitable dynamic regimes. In such conditions an accurate predetermination of the parameters and constructive solution by modeling and simulation of the given dynamic operation, becomes a mandatory step. In this aim, in the present paper a novel mathematical model of the high power salient pole synchronous machine (SPSM) is elaborated. We proposed to consider especially the effect...
Design of tunable and dual/multi-band metamaterial based perfect microwave absorber
Dincer, Furkan; KARAASLAN, MUHARREM; ÜNAL, EMİN; Sabah, Cumali (2015-01-01)
Tunable and multi-band metamaterial (MTM) based perfect microwave absorber (MA) is designed, implemented, and characterized. Firstly, dual-band MA with has two distinct resonances is investigated both numerically and experimentally which is also tested according the incident angle and polarization independencies. Then, the modified versions of MA are investigated and compared with respect to their absorbance, mechanical tunability, and multi-band characters. As a result, the suggested MAs with perfect absor...
Influence of Phase Magnetic Couplings on Phase Current Characteristics of Multiphase BLDC Machines with Overlapping Phase Windings
Bostancı, Emine; Plikat, Robert (2015-09-01)
Multiphase brushless dc (BLDC) machines are implemented in electric and hybrid electric vehicle applications due to their high torque/power density, good fault tolerance capability, and low torque ripple. Moreover, the per-phase converter rating can be reduced by increasing the phase number. However, the number of magnetic couplings between phases increases with the phase number, and these magnetic couplings can have an important influence on the machine performance. Therefore, they need to be considered in...
Modelling and Precalculation of Additional Losses of Inverter Fed Asynchronous Induction Machines for Traction Applications
Muellner, F.; Neudorfer, H.; Schmidt, E. (2011-09-10)
The inverter supply of asynchronous induction machines for traction applications has a major influence on both electromagnetic and thermal performance. In addition asynchronous induction machines used with traction drives of rail transportation vehicles have different design strategies compared against commonly used standard machines. Generally, the design of these machines requires high electromagnetic and thermal stress. Thus, the additional losses caused by the inverter have to be considered with the ini...
Citation Formats
Y. B. Yılmaz, “Design of synchronous reluctance machines with a wide speed range,” M.S. - Master of Science, Middle East Technical University, 2021.