Commissioning And Research On 220kV Dalang Digital Substation Equipment

With the economic reform and open up,China's economy has progressed enormously.Urbanization and people's living condition have been continuously improved,and the corresponding demands for domestic & working electricity have become even greater.Pearl River Delta's electricity load has increased year by year with the economic development.The development of substation automation technology and the application of microcomputer protection have largely improved the automation & management level of the power grid.However,due to the inconsistent communication protocol between the substation automation system and the protection equipment,the system is difficult to integrate seamlessly and the life cycle is shortened.Due to weak collaboration between equipment,system maintenance work is heavy and upgrading is difficult.Meanwhile,the controlling-signal transmission and data collection of the primary and secondary equipment are realized by a large number of cable connections,which not only wastes large amount of material,but also can't achieve isolation between high and low voltage equipment.With development of electronic transformers & intelligent high-voltage equipment and computer technology,online detection & substation operation training simulation have become mature,making the construction of digital substation becomes achievable.Besides the latest international standard IEC61850 supplies a comprehensive standards for digital substation,making substation automation system all-digital become inevitable.Compared with traditional substations,digital substations have great differences both in hardware and software.Traditional substation testing methods are no longer applicable.Therefore,deep study of digital substation testing & debugging methods and summarizing the debugging scheme have large practical value.This paper takes the 220 kV Dalang digital substation as subject.Firstly,it introduces application technology of key equipment in substation,including working principle and application of electronic transformer & merging unit & intelligent terminal as well as technical characteristics of digital substation system based on IEC61850.We develop a practical test program,basing on the study of the working principle and technical characteristics of these devices.In the scheme,the secondary current loop polarity in the electronic transformer test & programmatic control of substation & pre-power transmission are discussed.Next,in accordance with the established testing & debugging method,the 220 kV Dalang digital substation will be debugged,and the debugging results will be analyzed to ensure the substation equipment system is reliable.