A novel multidimensional space vector modulation strategy with voltage balancing capability is proposed for cascaded H-bridge rectifier. The optimal operating mode is chosen to achieve voltage of each cell balanced fast and accurately by analyzing the direction of input current and the region of AC reference voltage

and the relationship between DC capacitor voltage of each cell and average capacitor voltage. The system performs well under the adverse condition of unbalanced loads

and even no load

and realizes sinusoidal input currents and adjustable power factor. The selection method of optimal operating mode is described in detail

and a simple selection algorithm of optimal operating mode suitable for any number of cascaded H-bridge rectifier(CHBR)cells is summarized. The simulation and experimental results have verified the effectiveness of the new voltage balancing strategy. This work is supported by Hunan Provincial Natural Science Foundation of China(No. 2014JJ5007).