Abstract: In order to complete the tasks of transmitting, transforming, distributing, and supplying electricity at all levels in the power system, a transformer with a capacity of 5 kVA to 9 kVA is required for every 1 kW of electricity generated by the power generation equipment. Research on backup transformers with wide adaptability in key indicators such as rated voltage and impedance for parallel operation, flexible matching of parallel parameters with similar transformers, and the ability to spare any transformer of the same type and adapt to its operating status, while meeting the requirements of safe and reliable power operation.