Complete Load Compensation in a Distribution Network with a Single-Stage PV Grid Interface Converter

Recent promotions in renewable energy technology along with an increasing demand and the need for clean and cheap energy have led to an increasing trend towards distributed generation resources, especially solar cells, in distribution networks. Moreover, with the rapid development of electronic devices such as computers, televisions, and mobile phone chargers in the consumer sector and the use of power electronic devices such as converters in the industrial sector, the power quality of distribution networks has been seriously threatened. Therefore, it is very important to consider load compensation in distribution networks. In this paper, the use of a PV-grid interface converter for complete load compensation in a four-wire, three-phase distribution network is proposed. The proposed converter consists of a single-stage DC/AC inverter to connect solar cells to the grid. Maximum power point tracking of solar cells and injection of this power into the grid along with complete load compensation are done by the proposed DC/AC inverter. To achieve these aims, a new control strategy is proposed. Simulations wer performed in MATLAB/SIMULINK to evaluate the performance of the proposed structure and control strategy for the PV-grid interface converter. The simulation results for a four-wire, three-phase distribution system indicated complete nonlinear load compensation, reactive power compensation, load current harmonic elimination, and maximum PV power injection into the grid.