Simulation And Experiment Research Of Loss In High-speed Electric Spindle

High-speed electric spindle is the core unit of machine manufacturing. For this reason, the performance of electric spindle have much to work process accuracy. One kind of target to evaluate the performance of electric spindle is the losses in motor. The losses are harmful to the electric spindle. On the one hand, the idle work power increase because of the losses. Therefore, the work efficiency is reduced. In addition, the temperature in electric spindle increase with the increasing losses. Thus, the isolation material is affected, the output power decreases and even the motor is damaged. The generation of losses due to some reasons, for example, the pattern of power supply for electric spindle, the environment, the material of electric spindle, the installation and the operation and so on. So it is meaningful to find out the influence to electric spindle caused by those reason.The2D finite element model was built based on time-step finite element method to analyze the electric spindle and record the losses such as stator core loss, rotor solid loss and stator stranded loss. The motor model was built in Maxwell, coupling with simplore as the controlling circuit of electric spindle. By this way, the transient analysis was did on electric spindle.In this paper, the simulation analysis on influence to electric spindle caused by some factors was did based on time-step finite element method. Firstly, the influence to ceramic and metal electric spindle caused by loads was analyzed. The result shows both ceramic and metal electric spindle are affected by the loads. And the influence in ceramic electric spindle is lower than that in metal electric spindle. The optimum load field to electric spindle is got. Secondly, the influence on electric spindle caused by the carrier ratio was analyzed. The result shows that the carrier ratio can affect the electric spindle especially to metal electric spindle. When the carrier ratio is30, the losses of metal electric spindle are much higher than those in other carrier ratios. The losses fluctuation of ceramic electric spindle is less than metal electric spindle. Thirdly, the author analyzed the influence caused by air-gap. The total loss in ceramic electric spindle is minimum at the air-gap of0.38mm and maximum at the air-gap of0.36mm. When the air-gap is0.38, the total loss of metal electric spindle is lest. The total loss is most at the air-gap of0.34. Additionally, the deeper research was done on influence caused by air-gap eccentricity. The air-gap eccentricity can increase the loss. The total loss with air-gap eccentricity increases18.5%than the total loss without air-gap eccentricity in ceramic electric spindle and4.1%in metal electric spindle. The rotor solid loss and stator core loss are nearly not affected by the air-gap eccentricity.Based on the connection type loading method, the stator core loss, solid loss and stator copper loss was analyzed by electric spindle automatic test system. The result shows the copper loss of ceramic electric spindle is affected most by the loads, which increased81.4%compared with no-load condition. The stator core loss accounts the largest part of total loss. The influence to ceramic electric spindle caused by the loads is lower than metal electric spindle.