A simple DC bus voltage balancing control algorithm utilized in Vienna rectifiers

Vienna rectifiers are widely utilized in various industry applications due to low cost, high reliability and better EMI performance. However, the DC bus voltage balancing is always an issue to be considered due to the 3-level structure. Several DC bus balancing control methods are proposed during last decade. But these methods either require a large amount of calculations or cause inaccuracy at voltage zero crossing points. To avoid the aforementioned drawbacks, a simple DC bus voltage balancing method is proposed. The proposed method can balance the DC bus voltage effectively and requires very few calculation. The proposed method is validated by simulation and experiment.