ABSTRACT
Currently VSC-HVDC system, which is used for offshore wind farm, mainly focuses on two terminal HVDC systems. There are few studies with multiterminal MTDC for offshore wind farm. However, multi-terminal MTDC system has more advantages compared with the two terminal HVDC systems in the economy and flexibility, so this paper, which is based on the in-depth analysis of the two terminals VSC-HVDC system, applies the multiterminal HVDC system (VSC-MTDC) to the offshore wind farm. It establishes a new topology of multi-terminal HVDC system that contains energy storage device, and designs the control strategy of converter station and energy storage device, and puts forward a new controller that is adapted by the end of the power by oneself. Simulation results
1 INTRODUCTION
Problems of energy depletion and environment pollution have being becoming more and more serious in recent years, so offshore wind power, which is clean, safe, stable, and sustainable, is drawing more and more attentions (Lei 2005, Yang 2012). However, a regular offshore wind farm is always far away from land, and how to transmit power from offshore wind farms to the onshore load centers is a key problem. On the other hand, since the power of the offshore wind farm has the characteristics of randomness and volatility, the power quality of public power grid will be impacted greatly if large scale of wind power injected (Bao 2011).
