Link Capacitors Voltage Balancing in Diode - Clamped Multilevel Inverter

In all multilevel topology with several DC link, the voltage balancing problem of DC capacitors is a key problem. This paper proposes a new topology of chopper circuit for dc capacitor voltage balancing in diode clamped multilevel inverters (DCMLI). In the presented topology the number of switches is reduced respect to other proposed topology in literatures. Suggested topology is modular and has high reliability. Based on presented control system for chopper switches, only one switch is turn on at each time. Therefore the conduction and switching losses of chopper system are reduced. The presented simulation results show fast dynamic response of suggested chopper and reduction the voltage stress on its switches. Computer aided simulations are performed through MATLAB/Simulink software. The simulations results are presented to verify the performance of proposed chopper circuit and its control system for DC capacitor voltage balancing in diode clamped multilevel inverter. Keywords— Chopper, Capacitor voltage balancing, Diode clamped inverter, H-bridge.