Research on topological structure and control strategy of a hybrid on-load tap changer transformer

To address the issues of limited functionality and poor dynamic characteristics in traditional on-load tap changer transformers， this paper proposes a topological structure for a hybrid on-load tap changer transformer. This structure combines the efficiency and reliability of power-frequency transformers with the controllability of power electronic converters. By integrating back-to-back converters and designing corresponding control strategies， continuous voltage regulation and reactive power compensation for the on-load tap changer transformer are achieved. Additionally， the paper introduces a series voltage compensation method to provide fault protection for the load. Finally， an experimental model of the hybrid on-load tap changer transformer is built using MATLAB simulation software and an experimental platform. Both simulation and experimental results verify the correctness and effectiveness of the proposed topological structure and control strategy.