Implementation of A High-Frequency Link Five and Eleven level Cascaded Converter with PWM Controller

Abstract

Power Electronic converters, especially DC/AC Sinusoidal Pulse Width Modulation inverters have been extending their range of use in industry because of their numerous advantage .Recent advances in solid-state semiconductors have led to the development of medium-voltage power converters which could obviate the need for the step-up transformers of renewable power generation systems. The modular multilevel cascaded converters have been deemed as strong contenders for the development of medium-voltage converters, but the converters require multiple isolated and balanced dc supplies. This paper proposes the high-frequency link multilevel cascaded medium-voltage converter. The common high-frequency link generates multiple isolated and balanced dc supplies for the converter, which inherently minimizes the voltage imbalance and common mode issues. A multilevel phase shifted carrier based sinusoidal PWM switching scheme is utilized to reduce the complexity in control design. Therefore an identical H-bridge module is used to improve manufacturability and modularity. When comparing the five and eleven level inverter the voltage levels are increasing the THD value is decreases. The experimental results are analyzed and discussed. It is expected that the proposed new technology will have great potential for future renewable generation systems and smart grid applications.