Improvement of output voltage capability of a two stage direct power converter under unbalanced input voltages

Direct power converters (DPC), which has no energy storage, the converter output voltage capability is affected when the input voltage is unbalanced. This paper proposes the utilization of the clamp capacitor, which is normally needed to protect a DPC, to extend the operating range of a two stage DPC during unbalanced supply, preserving its theoretical output voltage capability. A comprehensive simulation study with analytical explanations justifies the proposed method. Experimental results using a laboratory prototype confirms the viability of the proposed active compensation technique