Space vector PWM technique for three-Level neutral point clamped converters with taking into account DC-voltage unbalance

This paper proposes a new technique of SVPWM for the neutral point clamped three-level converter. Taking the DC-voltage unbalance into consideration, this technique calculates the appropriate duty cycles of the space vectors. The duty cycles are analyzed and their limitations investigated. Computer simulations show that the proposed PWM technique gives an improvement of the input current and DC link voltage of the converter.