World’s First UHV Hybrid LCC–VSC MTDC Project: Experimental Tests and Onsite Commissioning

The WDD project is the world’s first multi-terminal UHVDC project that combines LCC-HVDC and VSC-HVDC. Such station-to-station hybrid UHVDC systems can make full use of the technical advantages of VSC to ride through the faults of AC system and improve the voltage support capability of power grids at the receiving end. One of the key challenges for the success of this project is to ensure that both the designs of the main equipment and the control functions meet the expected performance indices and technical specifications. For this, before being taken into operation, experimental tests based on a physical prototype followed by onsite commissioning are essential to verify the safety and reliability of equipment and system in various operating conditions. This article aims to introduce the experimental platform, key physical prototype tests based on the platform, and the key tests undertaken during system onsite commissioning.