Research on Topology and Control of Independent Controllable Phase Separation Hybrid Distribution Transformers

The Hybrid Distribution Transformer (HDT) combines the main winding of a power frequency transformer used for voltage conversion with a power electronic converter. HDT can utilize the controllable capacity of the converter to achieve other functions while performing voltage conversion. One of the main functions of HDT is to solve the power quality problems of loads. The current power quality issues in the distribution system are reflected in the fact that the three phases are not completely identical. Therefore, the phase independent and controllable power quality management method is more suitable for the current distribution system. The phase separated independent controllable hybrid distribution transformer (SHDT) proposed in this article uses three single-phase converters to solve the power quality problems of each phase separately. Considering the different solutions to voltage and current issues, the mode switching switches are adopted to change the series parallel connection relationship of the converter, achieving two types of compensation functions while independently controlling the phase separation. Based on theoretical analysis, the function of phase independent compensation and the effect of mode switching were verified in the simulation platform.