Research and Application of a Multi-channel Rapid Verification Method for TA Polarity in Substations

To address the low efficiency and high human error rate of conventional polarity verification methods for current transformers (TAs), this paper proposes a multi-channel rapid verification method specifically designed for substations. The method is based on the principle of transformer short-circuit primary current injection, and integrates multi-channel synchronous sampling, intelligent polarity determination algorithms, and winding amplification techniques to achieve efficient polarity verification for all TAs within a substation. Field results in a 500 kV substation demonstrate that the proposed method shortens the verification time from 63 h to 24 h, reduces the polarity error rate to below 0.3%, and effectively enhances the reliability and safety of substation commissioning.