摘要：针对反电势波形是准正弦波的无刷直流电机，采用无位置传感器矢量控制实现速度和电流双闭环控制。在零速和低速阶段采用IF起动方式，当电机运行到一定速度时，平滑切换到无位置传感器矢量控制方式，电机转子位置和速度的估计采用切换函数为变增益变边界层的Sigmoid改进型滑模观测器。实验结果表明，利用无传感器矢量控制方法可以实现无刷直流电机的正常起动、变速控制和稳定运行且具有良好的控制效果，该方案具有一定的工程应用价值。
关键词：无刷直流电机；矢量控制；滑模观测器；IF起动；Sigmoid
Abstract: For the brushless DC motor with sinusoidalwave back EMF,the speed and current double closedloop control has been realized by sensorless vector control.IF starting mode was used at zero speed and low speed,when the motor was running at a certain speed,its switched smoothly to the method of sensorless vector control that the rotor position and speed was estimated using an improved sliding mode observer of the sigmoid of switching function with variable gain and variable boundary layer.The experimental result shows that the sensorless vector control method can achieve the normal starting,variable speed control,stable operation of brushless DC motor and has good control effect,so this scheme has certain engineering application value.
Key words: brushless DC motor; vector control; sliding mode observer; IF starting; sigmoid