Efficient digital implementation of space vector modulation for three-level NPC converters used in wind energy conversion systems

Wind Energy converter systems require a sophisticated control structure to perform accurate and efficient power conversion. The converter modulation is always a challenging topic. This Paper presents an efficient timing study of Space Vector Modulation (SVM) for Three Level Neutral Point Clamped Converters (3L-NPC). Various patterns have been proposed with different segments numbers and dwell time distribution. By increasing the number of segments, a fast Digital Signal Processors (DSP) is required to ensure the efficient execution of the SVM algorithm. In this paper, a systematic method to select the SVM switching time in relation to the DSP sampling time is presented. Moreover, a new technique for constructing the switching patterns is introduced. The proposed calculations are verified analytically and through simulating a detailed multilevel converter. The results demonstrate the critical relation between pattern selection, SVM switching frequency, and the DSP sampling frequency.