Exploration on bus differential protection intelligent transformation of 500 kV conventional substation

This paper takes the intelligent transformation of Zhejiang 500kV Lanting Substation for example, as the practical intelligent transformation experience of conventional substation is so little at present, the paper puts forward four different retrofit schemes after deeply discuss on the retrofit scheme of bus differential protection intelligent transformation in a conventional substation, and compares their advantages and disadvantages as well as applicability. First scheme is the retrofit scheme by the transitional the sub computer of the bus differential protection; Second scheme is the retrofit scheme by conventional CT and intelligent terminal direct access digital bus differential protection; Third scheme is the retrofit scheme by digitization of interval after unified access digital bus protection; Fourth scheme is the retrofit scheme by bus splitting intelligent. After the paper to substation operation reliability and the project of transforming operational as a higher priority, and to compare their advantages and disadvantages as well as applicability· Decide to take some kind of retrofit scheme, and carry out detailed analysis and research retrofit scheme taken. It has a certain practical value, and explores transformation model of similar projects and provides practical ideas for implementing intelligent transformation of 500 kV substations with security and reliability.