The field calibration method of electronic current transformer in intelligent substation
The measurement accuracy of electronic current transformer (ECT) is related to correctly measure power energy, but the research on the field calibration methods of ECT is very little. The distribution of ECT in intelligent substation in china is introduced. According to the technical standards of GB/T 20840.7-Electronic Current Transformer, the field calibration method of ECT is proposed based on current comparative methods. The proposed field calibration method is used the communication protocol IEC 61850. The ratio difference f and angle difference δ of tested ECT can be directly obtained from the electronic transformer calibrator. The current working principle of primary devices and the operation method of primary devices are described in detail, when using the proposed field calibration methods. Meanwhile the secondary basic principle and working mechanism of the proposed method is studied. The field calibration results not only demonstrate the effectiveness and accuracy of this paper's content, but also show that the tested ECTs can be used 0.2S level power meter transformers. The research results of this paper can provide technical supporting for the commissioning and maintenance of power energy metering in intelligent substation.