Research On Performance Of Switched Reluctance Motor For Crane

Switched Reluctance Motor(SRM)is a mechatronics variable speed special motor.Its advantages include excellent starting performance,high reliability and fault tolerance.In addition,the structure is simple and the speed range is wide.Generally speaking,the traditional crane adopts a three-phase induction motor,which has a large starting current,a small starting torque,and low efficiency at low speed operation.All of these make it difficult to meet the requirements of high efficiency and high reliability of modern crane motors.The introduction of efficient,highly reliable and energy-saving switched reluctance motors to the field of cranes has important engineering and practical value for the upgrading of the crane industry.This thesis focuses on the performance of the crane SRM,aiming at the structural characteristics of the switched reluctance motor,the magnetic circuit characteristics and the nonlinear switching characteristics of the energized phase during operation.A 5.5kW three-phase 12/8-pole crane SRM is used as the research object to establish a two-dimensional physical finite element model.Based on electromagnetic field theory and time-step finite element method,the electromagnetic field distribution of switched reluctance motor is calculated.The two-dimensional static electromagnetic field calculation model and two-dimensional transient electromagnetic field coupling calculation are established.Besides the calculation and analysis of the electromagnetic performance of the crane SRM,the model also carried out a prototype experiment to verify the accuracy of the two-dimensional physical model.The effects of rotor initial position angle,starting mode and starting current on the starting performance of switched reluctance motor are analyzed and studied.The starting process of switched reluctance motor is also checked.In this paper,the vibration of the motor is analyzed from the perspective of the body by calculating the harmonic frequency and natural frequency of the radialelectromagnetic force of the prototype.Based on finite element method,the starting performance and running performance of switched reluctance motor are studied in two aspects: stator and rotor pole arc coefficient and air gap length.