A Three-phase Combined Transformer with Characteristics of Anti-leakage current and Anti-electromagnetic Interference

The three-phase combined transformer is a frequently-used metering equipment in distribution network, so it is of great significance to ensure its metering accuracy. Researches show that if a three-phase combined transformer is qualified when using the single-phase detection method, it may not be qualified according to the three-phase detection method, so the metering performance of the three-phase combined transformer must be improved. In this paper, the designs of anti-leakage current and anti-electromagnetic interference are proposed to improve the error performance of the three-phase two-element combined transformer, and its metering performance before and after the improvement is compared. It can be found from the results that the anti-leakage current and anti-electromagnetic interference design can effectively reduce the effect caused by leakage current and inter-phase electromagnetic interference, and the three-phase two-element combined transformer with this design has better metering performance.