Enhancing PV hosting Capacity of a Qatar Remote Farm Network using Inverters Ability to Regulate Reactive Power-a Case Study

Power quality issues pose severe challenges in realizing large-scale photovoltaic (PV) integration into the low voltage (LV) networks, and therefore determining PV hosting capacity in such a network becomes a complex and important task. This paper investigates PV hosting capacity of a Qatar based radial rural farm/small scale industrial network. Typically, this kind of network experiences huge variation in local demand during different times of the summer days and nights, requiring the network to operate both in power export and import modes. These two modes require contradictory tap settings for the transformers with off-load tap changing (OfLTC) mechanism. If the tap setting is not optimized and other mitigation measures are not taken, the PV hosting capacity of LV buses in such networks can severely be limited. This problem worsens further if the transformer has already been set at either -1 or -2 in order to boost the downstream bus voltage. This paper proposes utilization of PV inverters, designed with capability of regulating its reactive power and power factor, for enhancing the PV hosting capacity. Simulation results show that the PV hosting capacity can, substantially, be increased with the proposed approach (up to 95%), compared to a traditional practice of deploying PV inverters designed to operate at unity power factor.