R&D and application of voltage sourced converter based high voltage direct current engineering technology in China

As a new generation of direct current (DC) transmission technology, voltage sourced converter (VSC) based high voltage direct current (HVDC) has been widely developed and applied all over the world. China has also carried out a deep technical research and engineering application in this area, and at present, it has been stepped into a fast growing period. This paper gives a general review over China's VSC based HVDC in terms of engineering technology, application and future development. It comprehensively analyzes the technical difficulties and future development orientation on the aspects of the main configurations of VSC based HVDC system, topological structures of converters, control and protection technologies, flexible DC cables, converter valve tests, etc. It introduces the applicable fields and current status of China's VSC based HVDC projects, and analyzes the application trends of VSC based HVDC projects both in China and all over the world according to the development characteristics and demands of future power grids.