Research on SVPWM Control Strategy of Three Phase VIENNA Rectifier

摘要

Aiming at the problem of neutral point potential fluctuation and three phase current zero crossing distortion in Vienna rectifier. A high performance Vienna rectifier with small midpoint potential fluctuation and small distortion at zero current is designed. The midpoint voltage balance control is achieved by adjusting the action time of the positive and negative small vector. A seven-segment and five-segment combination vector synthesis method is used to suppress the three-phase current zero-crossing distortion. In order to simplify the control process, the target vector is first rotated into the first large sector, then the three-level space vector plane is converted into a two-level space vector plane, and then SVPWM modulation is performed on the two-level space vector plane. The simulation model of the system is built on the Matlab/Simulink software platform. The simulation results show that the control strategy has good stability and dynamics, the PF value is above 0.99, the THD is 3.53%, the midpoint potential fluctuation is small and the current zero distortion is suppressed obviously.