Analysis Of Control And Protection Software Of High Voltage DC Transmission System

To meet the needs of load growth in East China and South China, the Chinese government has speeded up the"West to East electricity transmission"project. After Ge-nan, Tian-guang, San-chang and San-guang HVDC transmission projects went into production, China's HVDC transmission technology has gone up to a new stage.This paper reviews the field of Control and Protection Software in Three Gorges-Changzhou HVDC transmission project, which is one of the largest power transmission projects in the world using ABB's"MACH2"power technology. After 10 months debugging, 500 items testing, we found several critical defects such as"OLT testing unsuccessful","converter transformer tap action frequently"etc,which may cause potential troubles in HVDC transmission's reliability and safety.In this work we examine those defects and give an analysis in detail. By comparing and excluding the potential possibilityof defects, we found several faults exist in software logic which caused by immensity of system,complexity of interface,tight schedule and etc. After rectification of software logic, we did simulation test and it show that we solved"OLT testing unsuccessful"and"converter transformer tap action frequently"successfully. And it performed well in reality.