12th IEEE International Conference on Compatibility, Power Electronics and Power Engineering (CPE-POWERENG), Doha, Qatar, 10 - 12 Nisan 2018
In this study, a MISO (Multi-Input Single-Output) DC/DC converter is integrated with a three-level NPC (Neutral Point Clamped) inverter to use it in photovoltaic energy systems. For this purpose, separated panel groups are connected to common DC bus through a double-layer MISO converter. Each power layer is controlled with MPPT (Maximum Power Point Tracking) algorithm. Converter output is connected to the NPC inverter that operates as grid interactive. Both the current control and voltage balancing operations of the inverter are achieved using model predictive control (MPC) techniques. The proposed model and its control architecture is tested in MATLAB/Simulink platform. Furthermore, a real prototype of the three-level NPC is carried out to analyze the voltage balancing performance of the proposed model by realizing its THD analyzes. Both the simulation and the practical tests show that the system successfully executes all tasks such as power sharing, current control and voltage balancing.