The Impact of the Shunt Reactor(s) Location on Offshore Wind Farm Power Export System on Zero-Missing Phenomenon and Switching Overvoltages—The Case of a Polish Power System

The observed development of offshore wind farms has resulted in an increasing presence of long extra-high voltage cables, with lengths ranging from 10 to 200 km. These cable lines are compensated for by a shunt reactor(s). The transient states that accompany switching operations, in this type of line, cause a number of challenges. There are slightly different and more dangerous phenomena than in classic uncompensated lines. One such phenomenon is the zero-missing phenomenon. The most effective methods for mitigating these phenomena are still under investigation and comparison to identify the optimal countermeasures. Applying a single minimization countermeasure often leads to avoiding one phenomenon (e.g., zero-missing phenomenon) while enhancing another (e.g., switching overvoltages). This can challenge designers, as they must consider the trade-offs between these competing objectives. The added value of this article is an analysis of the impact of the compensation level and its distribution (shunt reactor(s) location) in the offshore wind farm power export systems on zero-missing phenomenon and switching overvoltages. These analyses are supported by simulation cases mapping the case of the Polish power system. The results of the presented analysis are very important in light of a dynamic development of offshore wind farms and may be utilized by designers of power export systems, and can mitigate the significant risks occurring in such systems during energization cable lines.