Synchronization effects on power transients in distribution networks with grid connected photovoltaic generation

The high level penetration of distributed generation in power distribution systems has not only improved the power quality but also generated other challenges. The challenges are related to the interconnection of different power generation units and the need to keep the power delivered to the end user at the standards levels. Different controllers are implemented to simplify interconnection of a distributed generation with conventional power grids. The control process is mainly about keeping the voltage amplitudes and angles of the distributed generation unit and the power distribution network in a loop to detect the right instant to operate. In the present paper, a deep analysis of the effect of voltage synchronization in the transients behavior of a distribution network with a connected photovoltaic power generation system is conducted. The currents delivered by the two power sources are evaluated at different voltage angles between the two sources during the interconnection. The influence of voltage synchronization is also examined for transients overvoltages from capacitor bank operation. The workflow in this paper provides an insight to the phenomena and useful details to consider when designing a controller for interconnection of a photovoltaic power generation to a conventional power distribution network.