Forced Heat Dissipation Analysis And Pipeline Optimization Design Of Mine Electric Wheel-side Motor

Permanent magnet motors have been widely used in mining machinery due to their large operating current and high power density.At the same time,due to the high power density of the motor and the harsh installation environment,the electromagnetic load and heat load generated during operation are also high.The temperature of the insulating material and equipment determines the threshold for the use of the motor.In order to make the motor work safely and efficiently,the temperature of the motor is maintained within a reasonable range,so the thermal management research and design of the motor is particularly important.In this paper,the finite element magnetic-thermal coupling model analysis method will help to calculate the heat dissipation temperature field of the motor,and realize the multifield coupling model and system-level optimization design calculation of the high power density motor.The traction motor of a large mine electric vehicle is taken as the research object.Based on the theory of computational fluid dynamics and heat transfer,the basic assumptions and corresponding boundary conditions are given.Based on the Maxwell-Fluent unidirectional magnetic-thermal coupling method,the finite volume method is used to couple the threedimensional fluid field and temperature field control equations.Combined with the cooling structure and axial ventilation performance characteristics of the motor,a 1 / 4 magneticthermal coupling periodic boundary calculation model of the motor is established,and the numerical simulation of the steady-state temperature field of the motor is realized.Combined with the operation characteristics of the motor,through the analysis and research of the temperature field under three typical working conditions of the motor,the hottest temperature area inside the motor is determined,and the influence factors on the temperature field distribution and heat transfer mechanism are analyzed to obtain the accurate internal temperature field and flow field structure characteristics of the motor.Under the guidance of the measured data of the maximum temperature and pressure drop during the operation of the motor,the mathematical calculation model of the internal heat transfer of the motor is formed based on the Newton cooling formula,and the influence of the inlet fluid parameters of the motor on the temperature field and internal flow field characteristics of the motor is analyzed.Based on the original ventilation pipeline model,a scheme of optimizing the flow field structure in the pipeline by adding deflectors is proposed.In this paper,through the calculation of the pipeline resistance of the motor cooling system of the actual running vehicle,the second generation fast non-dominated sorting genetic algorithm NSGA-II is used for multi-objective optimization.According to the Pareto optimal knot set,the wind pressure and flow required to meet the motor cooling requirements are obtained,which provides a reference for the fan selection of the motor cooling system.