Modified flower pollination algorithm for optimizing FOPID controller and its application with the programmablen-level inverter using fuzzy logic

Ann-level multilevel inverter for PV connected systems is proposed in this paper. The proposed inverter is the combination of a buck-boost converter and an H-bridge inverter ((BH)-H-2 multilevel inverter). This system produces a constant AC output voltage with multilevels for a PV connected system with few number of switches. With the proposed inverter, the constant output voltage level is obtained from the PV system irrespective of the variable irradiance. Any number of levels is achieved by varying the duty cycle of the buck-boost converter over a wide range using an n-level generation algorithm. Thus, many numbers of levels can be attained in the output voltage which reduces the THD significantly. The voltage regulation process is performed by designing an optimized fractional-order proportional integral and derivative (FOPID) controller. The FOPID controller provides improved voltage regulation characteristics through the optimization of parameters of controller with the use of modified flower pollination algorithm. The proposed configuration is designed and implemented in MATLAB Simulink. The quality of output, their harmonics and the output resolution time are evaluated for various input voltages and for various numbers of output levels.

Automated summary

An Ann-level multilevel inverter for PV connected systems is proposed in this paper, combining a buck-boost converter and an H-bridge inverter to produce a constant AC output voltage with multilevels. The system allows for varying levels of output voltage by adjusting the duty cycle of the buck-boost converter using an n-level generation algorithm, significantly reducing THD. The voltage regulation process is enhanced with an optimized FOPID controller and modified flower pollination algorithm, improving voltage regulation characteristics.