Study On Data Measuring System Of 220kV Active Electronic Current Transformer

Nowadays, stable electricity supply is an essential part of our society. The safety and reliability of power system is the reliable guarantee for the development of the society and economy. The current transformer is a kind of important device, using in the online monitoring of grid in the power system. With the development of technology, there is a trend that new type of electronics current transformer will replace the traditional electromagnetic current transformer gradually, and it will be the developing direction of current transformer in the future.The active current transformer based on air core coil is a typical kind of electronics current transformer. This thesis is undertaken to introduce the operation principle of electronics current transformer, and designed a set of active current transformer for 220kV voltage grade, combining with the practical needs of the power system at present. Attention is paid to data measurement system in the primary side.There are three parts contained in Data measurement system, including the primary converter, transmission interface and power supply in the primary side. All of them match with air-core current transformer. In terms of the characteristics of high voltage, this thesis designed the protection of the primary converter, and optimized the primary measuring circuit. It also designed the cold standby system for the power supply in the primary side, which contains the small CT as the main power supply, and the laser power supply as the auxiliary one. At last, the thesis made correlational linear tests for every part of circuit of the system.