Research On Design And Thermal Characteristics Of Mine Direct-drive Switched Reluctance Motors

Switched reluctance motors(SRM)are widely used in the industrial field due to their advantage of robust structure,high efficiency,low cost,strong fault tolerance,good speed control performance and high reliability.The application of SRM in various aspects of industry remains to be studied.In mine industry applications,traditional 1500 rpm induction motors are used to connect with Raymond crusher at 105 rpm by gear transmission system,the entire system needs gear drive connection.The efficiency of the system is low,and it requires a large driving force of the motor.This paper mainly studies a mine direct-drive switched reluctance motor,which has the advantage of directly driving Raymond machines.Firstly,a switched reluctance motor with power of 75 kW and 72/48 poles is designed,Using the motor design theory to get the preliminary design of the motor structure size,then combining design theory with the simulation software to analyze the changes of the average torque and torque ripple by the change of motor parameters.The size of the motor is optimized to gain the final design parameters.The static and dynamic characteristics of the motor is studied and using ANSYS Maxwell software to establish the motor model for simulation analysis,including the simulation of the motor's magnetic density distribution cloud diagram,the rated working state torque,operating current,and motor efficiency.The result of simulation shows that output torque is large and the winding current is reasonable.The efficiency of the entire drive system is as high as 90.19%,which verifies the rationality of the designed motor.For the thermal characteristics of the motor,first ly studying and calculating the copper loss and iron loss of the switched reluctance motor to obtain the heat generation rate of the motor,using the ANSYS Workbench software to establish the motor model,calculating the motor convection heat dissipation coefficient of the surface,finally simulating and analyzing the temperature change of the motor during rated operation.Studying the thermal characteristic of the motor is based on temperature simulation results,providing the reference for the reliable operation of the motor.Finally,an experimental platform is set up to get the data when motor is running,the experimental results are compared with simulation results to verify that the motor output parameters were reasonable and reliable.Hot surface resistance was used to measure the temperature change of the motor during operation.The simulation results and the experimental results are analyzed to verify the reliability when the motor is working.Such a SRM is constructed and passes experimental tests.Simulation and experimental results show that the motor has better performance in mining applications and can replace induction motors in the mining industry.