Abstract:

As a kind of three-level rectifier,the mid-point potential of Vienna rectifier also has the problem of triple frequency fluctuation.Aiming at the problem of mid-point potential fluctuation,the current solutions are mainly to inject zero sequence to suppress the mid-point potential fluctuation.Firstly,this paper analyzes the principle of mid-point potential fluctuation and obtains the factors influencing the mid-point potential fluctuation and its fluctuation law.Secondly,according to the space vector modulation method,the mid-point potential control principle is analyzed,and the space vector modulation strategy is proposed.Finally,an experimental platform is built to verify the effectiveness of the proposed method.

Key words: VIENNA rectifier, midpoint potential, space vector modulation, mathematical model