Switched inductor impedance source inverter using third harmonic injected constant boost control

The performance of the conventional impedance source (Z-source) inverter can be improved by employing an advanced dc-dc enhancement technique called Switched Inductor (SL) technique which leads to the development of an enhanced impedance source inverter called "Switched Inductor impedance source inverter". The proposed inverter is capable of providing high voltage boost inversion ability than conventional inverter due to the presence of the SL impedance network that couples the dc power source and the inverter circuit. The operation of the proposed impedance network is similar to the conventional impedance network All the existing PWM control strategies for impedance source inverter can be used for this inverter. This paper presents an efficient PWM control called "Third harmonic injected constant boost control" for the proposed inverter. A detailed analysis of the improved topology is given. Simulation results are shown to verify the proposed circuit and analysis.