Improved Modified DTC-SVM Methods for Increasing the Overload-capability of Permanent Magnet Synchronous Motor Servo- and Robot Drives – Part 2
Direct torque control with space vector modulation (DTC-SVM) is one of the most popular methods in the case of permanent magnet synchronous motor drives due to its excellent torque-control capabilities. This method facilitates a very high torque-control dynamic performance which is an especially important requirement in the field of servo- and robotic applications, thus making DTC-SVM a natural choice in these cases. In this article simplified forms of the Improved Modified DTC-SVM (IMDTC-SVM) method that has been introduced in Part 1 are presented and it is proven that these methods have a very high overload-capability as well, they are stable during overload-conditions, while the torque-control dynamics and the torque-ripple generated are practically identical with those of the classical DTC-SVM, the MDTC-SVM and the standard IMDTC-SVM. Although the simplified forms have a somewhat lower overload-capability than that of the standard IMDTC-SVM, they have a significantly simpler structure, they require much less computation and the tuning of the complete control system is in one case much simpler.