Thermal Analysis And Cooling Approach Design Of Axial Flux Machine With PCB Winding

As a new type of high performance machine developing in recent years,axial flux permanent magnet synchronous machine(PMSM)is widely used in many fields such as military defense,spaceflight,electromechanical integration products and so on.The study object of this paper is the axial flux PMSM with a printed circuit board(PCB)stator winding and the NdFeB permanent magnet material,which has a high coercive force.The PCB winding will contribute to a closer structure,a lighter weight and a higher efficiency.However the small volume and high power density result in a high requirement of thermal performance of the machine.The machine?s temperature rise will affect not only its service life,its insulation,but also its operational reliability.Therefore,it is necessary to analyze and calculate the temperature field of axial flux PMSM with PCB winding and make some research on cooling approach.The finite element method(FEM)was used to study the temperature field in this paper.A three-dimension temperature field mathematical model was established and the heat source was analyzed and calculated according to the magnet filed distribution.The heat transfer process between the stator and rotor as well as the rotor and frame were dealt equally as the thermal convection according to the heat transfer theory.The distribution of the temperature field was got.A prototype machine was manufactured and experiments were conducted to test the thermal performance.Finally,some factors which could affect the temperature field were discussed,and the impact of the contact area between the frame and the PCB stator on machine temperature field was analyzed.To solve the machine?s over-heat problem,the temperature rise was decreased by increasing the contact area between the frame and the PCB stator.The analysis result will contribute to the optimization design of this machine and provide some reference for the research on the cooling approach.