基于双电阻的变频控制器交流电流采样方法研究

摘要

In order to solve the problem of sampling blind area in high frequency state of the variable frequen-cy controller,the sampling method of AC current with double resistance is studied,proving the AC value can be calculated by sliding mode observer. Simulation results show that the method of double resistance alterna-ting current sampling avoids the problem of blind area of current sampling in high frequency region and im-prove the accuracy of sampling current. The output torque of the system is more stable and the torque fluctua-tion range is smaller.%为解决双电阻直流电流采样在变频控制器高频状态下存在的采样盲区问题,对双电阻交流电流采样方法进行研究,论证其采样后的交流电值可以通过滑模观测器的运算,达到控制电机输出转矩的目的.仿真结果表明:这种双电阻交流电流采样方法避免了电流采样在高频区域中出现的盲区问题,提高了采样电流的精确度,使系统的输出转矩更加平稳,转矩波动范围更小.