Cascaded flying capacitor half bridge inverter for power rating enhancement in PV based inverter system

摘要

Solar Photovoltaic power generation systems are progressively widespread with the rise in the energy demand, to reduce consumption of fossil fuels and the concern for the environmental pollution around the world. Also multilevel inverters have gained additional attention within the field of energy distribution and control due to its various advantages in high-power medium-voltage applications with low harmonics. This paper proposed an improved Hybrid Level and Phase-Shifted Sinusoidal Pulse Width Modulation (HLP-SPWM) technique for a modular 5-level Cascaded Flying Capacitor Half Bridge (CFCHB) Inverter topology that is employed for PV system connection for improving the power quality of the inverter output voltage, and increase in its power rating. This improved modular cascaded multilevel topology helps to improve the efficiency of PV systems. Also to meet better use of PV modules and maximize the solar energy extraction, a maximum power point tracking (MPPT) control scheme is applied. A performance comparison between 5-level CFCHB inverter with CHB inverter respective to harmonics content, voltage stress for the switches with photovoltaic cell as its input source is simulated by using MATLAB/Simulink.