Investigation And Comparison Of The Synchronous Reluctance Machines With Distributed And Concentrated Windings

This dissertation reports an appropriate design methodology for synchronous reluctance machines,their important technical issues,and possible solutions for electric vehicle drives.The synchronous reluctance machines are used in industries owing to their unique merits,such as robust rotor,fast dynamic response,and lower cost.Considering these superior properties,recently,this smart synchronous topology became more attractive for electrified powertrain applications in automotive industries.However,compared to the major requirements of the traction motors such as high torque and power density,low torque ripple,wide speed range,and the proper size,this machine is still under investigation.This thesis deals with a comparison of the electromagnetic performance for different types of synchronous reluctance machines,conventional full pitch distributed winding(36 slot /4 pole & 24 slots/4 poles),with fractional slot concentrated nonoverlapping windings(15 slots/8 poles,9 slots/4 poles & 6 slots/4 poles).The fruits of this research work are as follows:Firstly,in order to maintain the electromagnetic performance of the SynRM machine,the key parameters,i.e.,slot/pole combinations number and the rotor topologies,barrier shape are designed and optimized.Meanwhile,the current density,slot filling factor and specific dimensions,viz.,stator outer diameter,stack length and air gap,are designed to be constant.Secondly,focused on the SynRM machine with distributed windings to verify the appropriate design for achieving a higher performance by using finite element analysis JMAG Designer.This optimization is mainly focused on the torque maximization for a certain current.Torque ripple is also minimized to a practically acceptable value.The rotor geometry and performance constraints are considered.Finally,focused on the SynRM machine with concentrated windings,full geometrical parameter sensitivity analysis is also done to investigate the influence of the main multi-layer flux barrier parameters,i.e.,flux barrier width,length and position on the machine performance where the stator parameters are not taken into account.The second part of optimization is the design of a multi-layer flux barrier for the SynRM machine to study the impact number of rotors composed of one,two,three and four flux barriers per pole on its electromagnetic performance.Afterward,the performance of the 6-slot/4-pole SynRM with a concentrated winding machine and 24-slot/4-pole machine with distributed winding is compared.The result shows that the 24 slots/4pole DW-SynRM machine has better torque performance at the same load.