Research on the sampling reliability of process layer device in smart substation

The double A/D sampling circuit is applied in the traditional substation to improve the reliability of relay equipment. In the process layer, the double A/D sampling circuit of the smart substation have differences with the traditional substation, the malfunction of relay protection is possibility caused by the abnormal operation of a single component. In this paper, by analyzing the structure of the smart substation sampling circuit, the weaknesses of sampling circuit in the smart substation would be found out. This paper points out two hardware redundancy design methods and analyzes the advantages and disadvantages of these two methods. The application of these two methods could solve the malfunction of relay protection device which is caused by the damage of single component in smart substation.