Research On Amorphous Stator Processing Technology And Performance Of High-Efficiency Brushless Direct Current Motor

Amorphous alloy is known as a green soft magnetic material because of its energy-saving manufacturing process and excellent electromagnetic performance.Amorphous alloy is applied to replace the conventional silicon steel sheet material in the stator core of motors,which can significantly reduce the core loss and improve the efficiency of motors.However,amorphous alloy materials are very hard,brittle and sensitive to stress,so there are problems such as processing difficulties and the influence of processing process on the soft magnetic properties of amorphous cores,etc.Direct replacement of silicon steel sheet may lead to amorphous motor performance is not as expected,and the advantages of high efficiency and low consumption are not fully developed.It is very important to study the influence of processing process on the soft magnetic performance of amorphous iron core,explore the best process solution,analyze the loss correction method,and explore the motor optimization design method based on the performance of amorphous iron core on this basis,which is very important to give full play to the material advantages,improve the motor performance,and expand the motor application scenario.Firstly,to address the problem that the processing process has serious influence on the soft magnetic performance of amorphous cores,the influence of process parameters on the soft magnetic performance of amorphous cores is studied through annealing and dipping paint curing experiments,and it is determined that the annealing temperature is 400～420℃,holding time is 45～90 min,a magnetic field of 1840 A/m is applied during annealing,and the lamination coefficient is controlled at 0.91～0.94,1K101 amorphous cores can obtain Furthermore,the soft magnetic properties of the amorphous alloy specimens were severely deteriorated by the annealing and dipping paint curing process,and annealing of the specimens before dipping paint curing could reduce the deterioration to a certain extent;on this basis,the loss coefficient of the amorphous stacked core was fitted as a function of the alternating magnetic field frequency,and then the loss coefficient of the amorphous stacked core after the specific process was obtained.On this basis,the loss coefficient of amorphous stacked cores is fitted as a function of alternating magnetic field frequency,and then the correction factor of loss coefficient of amorphous stacked cores under different magnetic field frequencies is obtained after processing with specific technology.Secondly,the amorphous stacked stator with different process schemes is prepared by orthogonal test method,and the results of the multi-indicator test are analyzed by polar difference analysis through the formula scoring method,revealing that the order of the three factors are annealing temperature(factor A),stacking coefficient(factor C),and holding time(factor B)in order to determine the best process scheme,i.e.,1K101 amorphous alloy material at The material is annealed for 60 min at a transverse magnetization of 1840 A/m and 420℃.The stacking coefficient is taken as 0.94,and the amorphous stator is processed after impregnation and curing.Compared with the silicon steel stator of the same shape and size,the saturation magnetic induction strength Bs of the amorphous stator is slightly lower,but the maximum permeability μm is more than three times that of the silicon steel stator,the coercivity H_c is 86.5%lower,and the loss density Ps is only 1/6 of that of the silicon steel stator.Then,the performance of silicon steel motor,ideal amorphous motor,and amorphous motor considering the influence of processing process were analyzed by finite element simulation,and it was found that the direct replacement of silicon steel sheet with amorphous alloy would lead to the motor performance not as expected,and the advantages of high efficiency and low consumption could not be given full play.To address this problem,a 2D finite element model of the motor is rebuilt based on the amorphous core performance,and the response surface method is used to optimize the motor design,with the rotor outer diameter D,stator tooth width b and stator tooth slot depth h as optimization parameters,and with automatic wire selection settings,the motor efficiency is used as the optimization target,so as to determine the optimal parameter values.The optimized amorphous motor eliminates the magnetic circuit oversaturation phenomenon,the core loss is 1/3 of that of the silicon steel motor,the copper consumption is reduced by 3%,and the efficiency is increased to 82.1%,an improvement of 8.4%.Finally,the performance curves of amorphous alloy motors and silicon steel motors under different loads were tested using experimental methods and compared with the simulation results for analysis.It was found that amorphous motors have certain efficiency advantages over traditional silicon steel motors,and the advantages are more obvious under light loads,but as the load increases,the efficiency advantages of amorphous motors are gradually weakened until they disappear completely.The experimental results are consistent with the simulation results of the amorphous motor considering the processing influence,which confirms the validity of the simulation.