Pulse Width Modulation strategies and a novel mixed control method for diode-clamped five-level inverter

Five-level inverter has been applied to industry and railway traction to solve the difficulty in applying low-voltage or medium-voltage switch devices to high-voltage system. The basic principle of diode-clamped five-level inverter is analysed in this paper. Based on the analysis of diode-clamped three-level inverter, single pulse control method, pulse width modulation(PWM) control methods and a novel mixed control method for diode-clamped five-level inverter are presented. Simulation analysis and results are also given.