具有低速高性能的电压定向V/F控制方法

Novel stator voltage oriented V/F control method capable of high performance at low speed

针对传统的V/F控制方法低速性能差且转速精确度低的问题,提出了一种电压定向V/F控制策略。此控制策略在传统的V/F控制基础之上采用了一种电压提升方法来补偿定子电阻压降以使电机磁链幅值保持恒定,同时根据感应电机非对称T型等效电路提出一种滑差补偿策略,以改善系统的低速性能和转速精确度。与传统的V/F控制不同的是,该方法是根据定子电压定向进行同步坐标变换,其不需要复杂的矢量计算且易于实现。实验结果表明:采用该方法在0.3Hz满载情况下,电机能平稳运行,而且在不同负载大小和频率下,电机转速精确度都得到了明显提高。

A novel stator voltage oriented V/F control method for induction motor is presented in this paper to improve the low speed performance and speed precision. The control scheme was based on the popular constant volts per hertz （V/F） method and adopted a novel voltage boost method to compensate the stator resistor voltage drop keeping the magnitude of the stator flux constant. A novel slip frequency compensation strategy, based on the equivalent circuit of induction motor, was also introduced. This method reduced the steady-state speed error to almost zero. Different from conventional V/F methods, all the compensation and regulation were based on stator voltage oriented synchronous rotation frame transformation, which avoided complicated vector calculation and were simple to implement. The experimental resuits show that, by adopting the proposed method, the speed can be accurately controlled down to 0. 3 Hz with rated load torque and the speed accuracy is improved in various speeds and loads.