Zero dead-time PWM implementation method for reducing total harmonic distortion in 3-level NPC inverter

This paper propose Zero Dead-time PWM method in 3-Level NPC(Neutral Point Clamped) inverter. Each switch of conventional PWM method is performs to complementary switching and semiconductor switch devices have time difference between rising time and falling time. Therefore, dead-time is applied to rising edge of switching signal for prevent short circuit fault. But this dead-time cause distortion of output voltage and current due to signal difference between reference switching and real switching. These distortions are responsible for system instable and DC-Link voltage unbalance. Whereas proposed ZDPWM method does not shows output current distortion because dead time is not exist. The validity of proposed method is verified it through simulation.