New space-vector control strategies for three-phase step-up/down AC/DC converter

In this paper, an equivalent de duty cycle for the generalized zero-voltage space vectors is proposed such that control of the three-phase ac part and the de part of the converter circuit can be integrated to achieve the idea l characteristic of single-stage step-up/down ac/dc converter. Depending up on how many modes are chosen and which class of generalized zero-voltage sp ace vectors is selected to increase the equivalent de duty cycle, different control strategies can be obtained. It is seen that not only the control o f the six switches is simplified but also the deadtime circuit for avoiding short circuit of the same arm can be eliminated for the proposed converter . In addition, some guidelines for selecting the LC parameters are describe d briefly and experimental results given for verifying the validity of the proposed converter.