Design And Analysis Of Operating Characteristics Of Synchronous Reluctance Machine

The synchronous reluctance motor(SynRM),whose stator is the same with the induction motor and rotor with no winding,is driven by reluctance torque.Compared with the traditional induction motor,SynRM has higher efficiency on rating load and remains a high efficiency on a wide load range,which is in line with the national development direction of "energy conservation and environmental protection".So that SynRM has a great development potential in AC drive system.However SynRM exists the problem of low power factor and small output torque.SynRM's rotor structure is special and rotor magnetic circuit is complex,the motor's performance influenced by rotor structure seriously.It is difficult to use traditional magnetic circuit method to design SynRM.In this paper,the finite element analysis(FEA)simulation software Ansoft Maxwell is used to design SynRM's rotor and analyze the characteristics of the motor.In this paper,the structure features,operating principles and mathematical model of SynRM are analyzed,and the relationship between electromagnetic torque,power factor and Ld,Lq are derived,which provide a theoretical basis for SynRM design.The method of calculating inductance parameters is also introduced.Then the FEA simulation software is used to build SynRM model and analyze the relationship between rotor structure parameters(working air gap,the flux barrier layers,percent of air barrier and magnetic rib width)and Ld,Lq and saliency ratio.Through the simulation the rotor structure which has a good performance and suitable for processing is finally determined.After the structure of the rotor is concerned,the FEA simulation software is used to analyze the performance and characteristics of SynRM.By setting the magnitude and phase angle of current excitation to analyze the influence of current load on SynRM's performance,obtain the motor's inductance and electromagnetic torque characteristic.By building the FEA model of induction motor and SynRM whose stator are the same to analyze the external characteristic curves of two motors,compare the difference between the two motors,and summarize the advantages and disadvantages of SynRM.In order to further analyzing the impact of rotor structure on motor performance and exploring the possibility of improving motor performance,the genetic algorithm(GA)is used to optimum design to find a better rotor structure whose electromagnetic torque and salient ratio are large and torque ripple is small.This paper also proposes a method to calculate the inductance through measuring the angle 8 between voltage resultant vector and rotor cross axis.Finally,a prototype is made according to the simulation results.The inductance parameters and the external characteristic curves are measured through the experiment.The test results verify the feasibility of inductance measured method and the accuracy of finite element simulation.