Research on VSC-Based DC Collection system for Large Scale Renewable Energy Generation Clusters

With rapid development of advanced transmission technologies such as MTDC and DC grids, it may become one of main features for China’s future grids that collect large renewable energy generation using DC technologies, and eventually form AC-DC hybrid power grids with high proportion of renewable energy generation connected. At present, a few studies have been conducted using the DC technologies for collection of large-scale renewable energy generation and its cluster in China. The paper designs a typical multi-voltage DC grid for collection of large-scale renewable energy generation cluster. Based on the scenario of renewable energy generation cluster in China, the paper presents its DC grid topology accordingly. Then the model of multi-port DC Hub is proposed. Through a lot of transient simulations, the requirements for transmission capacity, voltage levels and control strategy of such a DC grid are also discussed. The results presented by this paper provide the reference for future research of using DC technologies for collection of large-scale renewable energy generation cluster.