The paper discusses the design of the current controllers for the induction motor (IM) drive where field oriented control is done in the rotor flux synchronous reference frame. The most common current control method is to use PI controllers alone – this is easy to implement and works well in most cases. A better scheme is to use decoupling compensation voltages in addition to the PIs, however, this is more difficult to implement and the decoupling voltages are often omitted. The paper compares the two current control schemes. The influence of the feed-forward decoupling voltages on the performance of the current loops is investigated in torque control mode and speed control mode. The theoretical findings are validated by simulations and experimental results.
Keywords: induction machine, current control, current decoupling