Implementation of a New Control Strategy for Diode-Clamped Multilevel Inverter in Distributed Generation
Keywords:
Buck converter, Distributed generation (DG), islanding, load current, NPC (Neutral point clamped), seamless transfer.Abstract
This paper presents a new control strategy for three phase inverter in distributed generation. This paper
analyses a new NPC technique based three phase inverter with grid connected system. The proposed control strategy
that enables both islanded and grid-tied operations of three phase inverter in DG. In addition the control strategy
composes of an inner inductor current loop, and a novel voltage loop in the synchronous reference frame. The inverter is
regulated as a current source just by the inner inductor current loop in grid-tied operation, and the voltage controller is
automatically activated to regulate the load voltage upon the occurrence of islanding. The NPC inverter needs a neutral
DC terminal which is provided by a buck converter. To review the effectiveness of the proposed system, the waveforms of
the grid current and the load voltage are distorted under non-linear local load with the conventional strategy. Finally,
the effectiveness of the proposed control strategy is validated by the simulation results using MATLAB/SIMULINK
software
