Comparison of Voltage Control by Inverters for Improving the PV Penetration in Low Voltage Networks

Voltage rise caused by reverse power flows and intermittency in renewable power is the main limiting factor for integration of photovoltaic(PV) generation in low voltage networks. Inverter voltage control techniques have been developed to provide effective voltage control and support higher penetration integration of PV generation. In this paper, the common Volt-VAR control, PF(P) and Q(U) control of photovoltaic inverter methods are detailed compared. A set of simulation study-cases have been designed based on a generic LV grid model, which is considered as representative for the Bornholm network. Observations of the influence of different Volt-VAR control strategies upon different electrical parameters on hosting capacity increase potential have been performed for variable PV penetration levels. Results show that inverter controls can greatly contribute the integration of PV in LV networks in the perspective of avoiding overvoltage.