The Design And Application Of Electronic Instrument Transformer In Smart Substation

Smart substation, which connects power generation, transmission, substation,distribution and utilization, is the key step of smart grid. Smart substation needs reliablemeasurement and accurate data, electronic instrument transformer is the idealmeasurement equipment. The research of electronic Instrument transformer application inthe smart grid makes a great contribution to the reliable measurement and relay protection.The main research content of this article are as follows:Firstly, smart substation and the demand for electronic instrument transformer areanalyzed. The Key Standards of smart substation, such as IEC61850and GOOSE, aresummarized. The problems existing in the use of electronic transformer are analysed.Based on the above research and analysis, this paper summarize the relations betweenelectronic instrument transformer and smart substation.Secondly, the working principle of electronic Instrument transformer of Rogowskicoil current transformer and capacitor pressure type voltage transformer is analyzed. Theinfluence of temperature on the two kinds of electronic instrument transformer is alsostudied. Temperature compensation resistance is studied, damping values of sensing headof Rogowski coil are analyzed and designed.The on-site test method and procedure of theelectronic transformer is introduced. Wiring Method of the electronic instrumenttransformer and its corresponding constraint condition are also mentioned.Thirdly, the usage of electronic transformers in a500kV smart substation is studied.This paper detailed describes the type selection and configuration principle of electronicInstrument transformer. The configuration process of electronic transformers and mergingunits are illustrated from each voltage grade. Based on the configuration strategy, thispaper studies the influence of the electronic transformer on the relay protection.