Closed loop control of Diode Clamped Multilevel Inverter with Integrated Maximum Power Point Tracking for Grid Connected Photovoltaic Application

A Three-phase Diode clamped multilevel inverter (DCMLI) based photovoltaic system for grid connection is proposed with different maximum power point tracking (MPPT). This photovoltaic (PV) system utilizes two conversion stages: algorithm for tracking the maximum power point and a DCMLI used as an interfacing unit. The maximum power point tracking is achieved with Perturb and absorb (P&O), Incremental conductance algorithm (INC) and a fuzzy logic controller (FLC), and the DCMLI regulates the DC link voltage and synchronizes the grid voltage and current in order to achieve unity power factor operation. The proposed system provides high dynamic performance in terms of Total Harmonic Distortion (THD) and power quality injected into the grid. The validity of the proposed system is confirmed by simulations.

---

Opisano trójfazowy przekształtnik wielopoziomowy DCMLI przystosowany do sieci fotowoltaicznej z układem śledzenia maksymalnej mocy MPPT. System wykorzystuje dwa etapy konwersji: algorytm do śledzenia maksymalnej mocy i przekształtnik użyty jako interfejs. Interfejs steruje napięciem DC i synchronizuje napięcie sieci.