Space-vector-based hybrid PWM for reduced line current ripple and common mode voltage in paralleled interleaved three-phase two-level converter

This paper proposes a hybrid space vector modulation (HBSVM) to reduce line current ripple while maintaining the optimal common mode voltage and zero sequence circulating current peak. The analysis reveals that the vector errors can be reduced by an equivalent basic vector with an adjustable length, which is synthesised by two basic vectors of the same vector angle. Then, a variable k is defined to denote the distribution of the two basic vectors. In addition, due to the implementation of k, a special vectors timing sequence is proposed. With the proposed generalised sequence, this paper investigates the current ripple over the switching period. Furthermore, we derive a map of the optimal distribution factor kopt to minimise the current ripple. Each 30° sector is divided into three subsectors; each applies kopt to minimise the current ripple. With the proposed two variables (p and q), a simple flowchart for kopt selection in the whole space vector plane is developed. The proposed HBSVM uses the optimal distribution kopt according to the position of the reference voltage, achieving the minimised line current ripple. The proposed HBSVM achieves the best line current quality while maintaining the optimal ZSCC and CMV peak, as validated by experiments.

Duke Scholars

Author Stefan M Goetz Psychiatry & Behavioral Sciences, Behavioral Medicine & Neur ...