Vienna Rectifier for a Wider Range of Load Variation using Mixed Mode Predictive Input Current Control

Vienna Rectifier refers to the three phase three switch three level boost converter, designed for operation in continuous conduction mode at full load condition. At a reduced load condition or input inductance, this rectifier operates in discontinuous conduction mode leading to inaccurate sampling of input current, poor power factor and dual mode operation wherein the THD is high. The proposed predictive input current control scheme does not consider the input current measurement, but yet improves the power factor, in addition to avoiding the dual mode operation by operating at constant switching frequencies, for each mode, based on the load condition. The input current is predicted using feed-forward components. This paper contains the simulation result of the proposed method, where it meets the IEC compliance requirements for harmonics.