Var Control Capability Analysis for a Hybrid Voltage Regulation Transformer

In modern power distribution systems, power electronics-based devices are designed to provide advanced functions, such as fast voltage regulation, flicker compensation, and var control, which cannot be achieved from the conventional step voltage regulators (SVR). This paper proposed a new topology of the hybrid voltage regulation transformer (VRT), combining voltage regulation and var control into one device. The feasibility and capability of var control are investigated for different load power factors and input voltage range considering the power converter capacity. The simulation results illustrate the feasibility of implementing var control while the load voltage is being regulated. The proposed VRT can regulate the reactive power for each feeder in the distribution system in addition to the voltage regulation function.