Comcore optical DC current transformers applied in Yu-E flexible DC back-to-back networking project have been put into operation

On June 24, 2019, south channel converter station of Yu-E flexible DC back-to-back networking project with the highest voltage level and the largest power transmission capacity in the world was officially put into operation. Later, the north channel converter station also successfully passed the 168 hour trial operation, so far, the whole project ended successfully. At the same time, Comcore optical current transformers (OCTs), which are applied to the start-up resistance side of south channel converter station and north channel converter station, have also been in live operation for four or five months, and have obtained the operative certificate issued by State Grid Hubei Electric Power Equipment Co., Ltd.

Yu-E flexible DC back-to-back interconnection project realizes the asynchronous interconnection between Southwest Power Grid and Central China Power Grid, which is of great significance to optimize the power grid pattern, promote the structural reform of energy supply side, and improve the level of power grid science and technology. Compared with the conventional HVDC system, the flexible HVDC system has stronger regulation ability, but it is easy to generate large instantaneous fault current when the flexible HVDC system fails. In order to effectively restrain fault current and improve the safety and stability of the system, the control and protection system of the flexible DC transmission system should have a fast response speed, which requires higher step response characteristics of the current transformer for the flexible DC transmission. The type test report issued by Xi'an High Voltage Electrical Research Institute shows that the step response time of Comcore FCA-01-420D-A OCT is 50us, and its measurement accuracy is 0.2 level, and it has excellent temperature stability and anti vibration performance, which can better meet the application requirements of Yu-E flexible DC back-to-back networking project.