SVPWAM modulation strategy for back-to-back converters to reduce harmonic and common mode voltage

ABSTRACT

This paper presents a new switching strategy by combining space vector modulation (SVM) and pulse amplitude modulation (PAM) techniques. The proposed method can eliminate harmonics and reduce power loss, leading to efficiency increment. Moreover, as one of the significant challenges in any modulation technique, the common-mode voltage is investigated. Accordingly, applying the proposed method in a conventional back-to-back two-level converter results in a substantial reduction of the common-mode voltage as well as the harmonic content of the systems’ input current fed by the power grid. Also, easy implementation regardless of the converter’s rating is the other advantage of using this method. Furthermore, applying this strategy does not add to the converter’s volume, weight, and cost. The appropriate selection of the active vectors, the arrangement of the switching sequences for the inverter and rectifier, as well as the modulation index of the converter are key factors in this technique. The performance of the proposed strategy is investigated through both simulations and experimentations on a back-to-back two-level converter prototype. The experimental results show that the proposed method reduces the common-mode voltage by more than 50%, reaching 87.2% efficiency, making the proposed method suitable for industrial applications.

KEYWORDS:

• Back-to-Back converter
• common mode voltage
• space vector modulation
• harmonic

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the Babol Noshirvani University of Technology [BNUT/389051/1401].