Local and Remote Cooperative Control of Hybrid Distribution Transformers Integrating Photovoltaics in Active Distribution Networks

This paper proposes a hybrid distribution transformer integrating photovoltaics (HDT-PV) with local and remote cooperative control in an active distribution network (ADN). HDT-PVs, regarded as promising devices with high reliability and easy engineering in ADNs, can not only realize the on-site maximum utilization of distributed solar energy but also solve the various power quality problems that follow. Moreover, the reactive power flow in the ADN can be optimized through remote cooperative control of multiple HDT-PVs. In this situation, the two objectives of voltage regulation and network power loss decrease are achieved in the ADN. If the power electronic device in the HDT-PV fails, the HDT-PV is able to work as a conventional distribution transformer by cutting off all power electronic devices and PV systems. Even when a small number of HDT-PVs malfunction, the system can still run stably. Finally, the simulation and experimental results demonstrate the effectiveness of the proposed scheme.