CASCADED POWER ELECTRONIC TRANSFORMER AND CONTROL METHOD THEREFOR

Disclosed are a cascaded power electronic transformer and a control method therefor, implementing power balancing between windings of different primary sides. The method comprises: calculating θi1 and Okps of an sth transformer and θj of a jth transformer, s = 1, 2, ..., and n; in same transformer, with the voltage of a first primary-side converter bridge arm serving as a reference, the electrical angle between the voltage of an ith primary-side converter bridge arm and the reference being θI1, I = 2, 3, ..., and m, the electrical angle between the voltage of a kth secondary-side converter bridge arm and the reference being θkps, k = 1, 2, ..., and r, and the electrical angle between the voltage of primary and secondary-side converter bridge arms of a jth transformer being θj, j = 2, 3, ..., and n; superimposing θj on the basis of θkps of the jth transformer to produce compensated θkps; and when compensated, putting θi1 and θkps of the sth transformer into use.