Grid-connection strategy with reduced current spikes for grid-Tie module-integrated converter

Module-Integrated Converters (MICs) are becoming an interesting option for residential photovoltaic (PV) applications because the PV modules are enabled s to work as plug and play devices. Reducing the costs and increasing the lifetime of the MICs are the main challenges for large-scale adoption of MIC technology. Particularly, current spikes during the connection of the MICs with the grid cause unnecessary oversizing of power components and lifetime decreasing. In this way, this paper presents a novel grid-connection strategy with reduced current spikes in order to achieve these goals. The proposed strategy does not require any controller transitions between the connection control mode and the steady-state control mode. Furthermore, the connection relay could be turned on at any instant without zero-cross switching constraints. Experimental results of a real prototype are provided in order to demonstrate the effectiveness of the proposed strategy.