Time Coordinated Control Strategy to Improve Voltage Balance and Regulation of Low Voltage PV Rich Networks

Typically, a PV-rich low voltage active distribution system (LV-ADS) suffers from voltage unbalance issue during high irradiance period. Lack of proper planning in deploying PVbased single-phase converters (SPCs) in the LV-ADS causes a high phase voltage unbalance factor (PVUF), leading to the tripping of three phase converters (TPCs). The IEEE 1547-2020 code does not mandate SPCs to undertake any preventive measure to reduce the PVUF of LV-ADS. The code recommends TPCs to participate in voltage regulation of the network. However, due to tripping of the TPCs, the voltage regulation degrades. Two new algorithms are proposed in this paper; coordinated leader-follower feedback-based algorithm and cluster selection algorithm which are combined together to resolve the abovementioned issues. The proposed approach is demonstrated in the European LV-ADS test bench to validate its superiority over IEEE 1547-2020 and SOCP based ACOPF methods.