Simulation And Experimental Verification Of Core Loss Properties For Induction Motor Based On Field-circuit Coupling Method

At this present stage,the motor has been widely used in the field of production and life with the rapid development of industry.According to statistics,nearly 70% of electrical energy in the motor is converted to other forms of energy in the electrical equipments.In the different categories of the motors,induction motors are widely used in various fields of national economy because of the high efficiency and good working performance.For the sake of alleviating the energy crisis and reducing the loss caused by the motor,many reseachers at home and abroad are studying deeply the operation efficiency of the motor.Core loss in the motor is becoming one of the key research topic.Meanwhile,the complex control performance of the motor is optimized by the development of inverter technology.Therefore,the performance of induction motor and the properties of core loss in the condition of inverter power supply have been paid attention by scholars all over the world.Firstly,this paper introduces the mechanism of magnetization in ferromagnetic materials of magnetic material,analyzing causing of hysteresis loss,eddy current loss and excess loss as well as calculation method of each loss,respectively.The common calculation model of alternating core loss and calculation model of rotating core loss in the cartesian coordinate and polar coordinates are presented.Secondly,using the rotating core loss data of silicon steel sheet,which is measured by the novel 3-D magnetic properties system,rotating core loss model in cartesian coordinate is validated.The composition and distribution characteristics core loss in the motor are analyzed.Then,taking three-phase squirrel cage induction motor Y2-132M-4 as an example,the field-circuit model coupling finite element is analyzed from the view of magnetic field and electric circuit considering the influence of stator end-winding and rotor end-ring.A software Simplorer is used to generate the waveforms of three-phase SPWM voltage and the Maxwell 2D electromagnetic transient field solver is used to establish electromagnetic analysis model of the motor,combining the two models to realize the foundation of the field-circuit model coupling finite element.The waveforms with time variation and trajectory of magnetic flux density at the different locations under the SPWM power supply are obtained.The different regions of alternating and rotating magnetization are analyzed,along with the influence on core loss.In addition,the waveforms and trajectories of magnetic density along the radial and tangential direction at typical position are presented.Finally,the platform for measuring core loss of induction motor is established.The core loss of induction motor under SPWM power supply is measured by no-load test.The simulation results are verified,and the better desired results are obtained.