Simple and advanced three dimensional space vector modulation algorithm for four-leg multilevel converters topology

In this paper, a novel three-dimensional space vector algorithm for four-legs multilevel converters is presented. It can be applied to active power filters or neutral current compensator applications for compensating harmonics and zero sequence using natural coordinates. This technique greatly simplifies the selection of the 3-D space where a given voltage vector is supposed to be found. The algorithm drastically reduces the algorithm complexity and the calculations of the active vectors with the corresponding switching time which generate the reference voltage vector. In addition, the low computational cost of the proposed algorithm is always the same and it is independent of the number of levels of the converter.