Closed-loop identification technology for the whole life cycle of the fixed defective state of relay protection equipment

Due to the multiplicity of fixed-value defect states of relay protection equipment, it is difficult to guarantee the effect of identification directly through a single indicator. Therefore, this paper proposes research on closed-loop identification technology for the full life cycle of fixed-value defect states of relay protection equipment. The generalized transformation ratio of the relay protection circuit is analyzed based on the CT basic transformation ratio, cable voltage drop correction coefficient, filter attenuation correction coefficient, and ADC quantization error correction coefficient. The relationship between the transformation ratio and the fixed value state of the relay protection equipment enables the identification of defective states. In the test results, the design technology can effectively identify fixed-value defects at different stages and to varying degrees.