Loss Analysis And Temperature Calculation Of Permanent Magnet Synchronous Motor

Permanent magnet synchronous motor have many advantages,not only its speed,power density,torque are higher than other motors,but also it has simple construction,small volume,as well as good environmental adaptability,so it is widespread in grinding machine,such as the flywheel energy storage,electrical engineering fields,electric cars and so on.The property of the magnet is easy to be effected is the defect of the permanent magnet synchronous motor,it will lead to the irreversible demagnetization and the damage of the motor.It is obviously that for the motor,reduce the temperature of the motor effectively is the guarantee to the performance of the permanent magnet synchronous motor.In this paper,using a kind of water channel,induce the temperature of the motor by design an optimized waterway.Analyzed the electromagnetic field,loss,temperature rise of the motor by the following methods,set a model,take analysis,finite element simulation and calculation method.The main content as follows:Firstly,calculated the loss of the machine.The loss of the motor can be divided into core loss,eddy loss,copper loss,mechanical loss and so on.Then analysis the causes of all kinds of loss,establish iron loss calculation model,through the analysis of the core magnetic field,getting the fitting of loss factor,decomposed the flux density wave which has affected the core loss,using the method of directly to the radial,tangential decomposition method and Fourier decomposition method respectively.Then take the numerical value into the formula to calculate loss values,comparative and analysis the results of the three kinds of calculation,ensure the cause of heat source temperature values.Secondly,analysis the steady-state temperature field of the motor.Use the three basic laws of the heat transfer and fluid mechanics as the foundation to find the way of the heat transfer,use the method of equivalent thermal network model,through the establishment of motor for motor nodes,each node method and process of heat transfer,write a program computing the temperature of each node,then obtained the motor temperature field distribution.Finally,study the effect of cooling structure of motor cooling performance,establish the structure of the cooling water channel size.Equivalent processing complex parts and materials to the motor,the motor temperature rise of 3D finite element simulation model is set up.Based on the loss of the motor electromagnetic field analysis,take the simulation to get the temperature distribution in each part of the motor,compared the result with the thermal network model analysis result.Examines the influence of cooling fluid inlet temperature,inlet flow rate and the influence of environment temperature on the rise of motor temperature,provide reference for the optimization of the rise of the motor temperature.