A novel space-vector current regulation scheme for a field-oriented-controlled induction motor drive

The system performance of an ac variable-speed drive directly depends on the current regulation. In this paper, a novel space-vector current regulation scheme for a field-oriented controller (FOC) is developed. Motor currents are regulated by generating appropriate inverter output voltage vectors via software-implemented comparators and a switching table. A switching table based on the angular coordinate enables the inverter to generate optimal voltage vectors. By introducing an additional triangular carrier signal to the output of original hysteresis comparators, a user-selectable high and fixed switching frequency can be obtained, further improving the driver performance. Experiments are made to verify the effectiveness and correctness of this proposed method. According to the experimental results, both simple hardware design and good current response can be attained.