For the future, a large‐scale expansion of offshore wind energy is expected in Europe. To collect this wind energy and to enable electricity trading between countries, an offshore network will be implemented in the North Sea. Maintaining a high level of security of supply at affordable costs is one of the key objectives in the design and operation of power systems and therefore, the reliability of offshore grids is an important topic of discussion. Whereas onshore, the security of supply is assured by reliability criteria like n‐1 redundancy, the same n‐1 redundancy might not be an economical solution for offshore networks. For todays (small) offshore networks, n‐1 redundancy is hardly economically justifiable, seen from a wind farm owner's point of view. The question then arises how the reliability of large‐scale offshore networks should be evaluated and what measures can be taken to maintain a high security of supply onshore. This paper aims at discussing this topic by reviewing the results of recent research work. It is found that whereas for smaller offshore networks reliability evaluation is mainly an economic analysis seen from a wind farm owner's point of view, for large‐scale offshore networks, it is necessary to consider the interaction of offshore–onshore networks in reliability analysis. It is proposed to analyze the reliability of combined offshore–onshore power systems in an integrated approach, such that various (offshore and onshore) measures can be considered to find the most economical solution.

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离岸电网可靠性分析-最新研究概述

未来，欧洲有望大规模扩展海上风能。为了收集这种风能并实现国家之间的电力贸易，将在北海建立离岸网络。以可承受的成本维持高水平的供应安全是电力系统设计和运行的主要目标之一，因此，海上电网的可靠性是讨论的重要课题。在岸上，通过n -1冗余之类的可靠性标准来确保供应的安全性，而对于n -1冗余而言，相同的n -1冗余对于海上网络可能不是经济的解决方案。对于当今（小型）离岸网络，n从风电场所有者的角度来看，‐1冗余在经济上几乎是不合理的。随之而来的问题是，应该如何评估大型离岸网络的可靠性，以及可以采取什么措施来维持陆上供应的高度安全。本文旨在通过回顾最近的研究成果来讨论这一主题。结果发现，对于较小的离岸网络，可靠性评估主要是从风电场所有者的角度来看的经济分析，而对于大型离岸网络，则必须在可靠性分析中考虑离岸-陆上网络的相互作用。建议以一种集成的方法分析组合的海上-陆上电力系统的可靠性，