Reliability and economy assessment of offshore wind farms

Offshore wind power resource, which is relatively stable, abundant, and with modest impact on the environment, is a kind of clean and renewable energy suitable for large-scale development. Offshore wind farms have different topological structures of the collection system, such as AC parallel type, DC parallel type, DC series type, single-ring type, and double-ring type. The purpose of this paper is to analyse reliability and economy for various topologies and provide an insight into wind farm construction. In this study, the topology structure of various offshore wind farms is introduced firstly. Then, the reliability assessment methods are proposed. The reliability of the chain wind farm is analysed with the reliability block diagrams, while the reliability of the ring wind farm is analysed by using the classification method. In addition, the economy is evaluated considering investment costs. The investment cost for each type of component is calculated separately, which contributes to assessing the investment cost of the whole offshore wind farm. Detailed results from a case study, which includes 96 wind turbines, demonstrate that the DC series–parallel wind farm has superiority in reliability and economy, as well as in terms of its potential applications.