Coordinated Voltage Control Strategy for Distribution Network with Power Electronic Transformer and Photovoltaic Power Supply

There are many problems in the traditional strategy of voltage regulation based on common transformer (OLTC) and static capacitors (SCs) in distribution network, such as slow regulation speed, discretization, limited regulation times, etc. The control mode of power electronic transformer (PET)is different from OLTC, which can make up for these problems. In addition, photovoltaic (PV) power supply has been widely concerned in recent years because it can provide fast and continuous voltage regulation. Therefore, this paper proposes a voltage coordinated control strategy including PET and PV. Firstly, the mathematical model of PET is established and a comprehensive forecasting method by time interval is adopted to predict the daily active power output of PV power supply, and then the control strategy of coordinated voltage regulation is proposed. Finally, the IEEE-33 bus system is selected and simulated by particle swarm optimization algorithm (PSO). The results show that the proposed control strategy is reasonable.