Voltage feed-forward decoupling and steepest tracking-differentiator based current control method of permanent magnet synchronous spindle

The d/q coupling effect of PI current controller in permanent magnet synchronous spindle drive system can't be ignored when the spindle rotation speed is high, which will degrade the performance of spindle drive system. This paper proposed a voltage feed-forward decoupling control method which used d/q coupling terms in spindle's voltage equations to compensate the command voltage of PI current controller, and d/q currents full-decoupling was realized. In addition, the conflict between overshoot and response speed inherent in PI current controller is difficult to resolve, which will deteriorate system robustness. This paper adopted steepest tracking-differentiator to arrange transient process for d/q current commands, so that the current values can track the commands more quickly and smoothly. Simulation results verify the feasibility and effectiveness of the proposed method.