The rapid expansion of offshore wind farms (OWFs) has created a pressing need for efficient and reliable power transmission technologies. A recent review published in the journal “IET Renewable Power Generation” highlights the potential of diode-rectifier-unit based high voltage direct current (DRU-HVDC) systems as a solution to this challenge. Led by Lujie Yu from the School of Electrical and Information Engineering at Tianjin University in China, the research examines the technical features and advantages of DRU-HVDC compared to other systems like modular multilevel converters (MMC-HVDC) and line-commutated converters (LCC-HVDC).
One of the main benefits of DRU-HVDC is its ability to facilitate the transmission of power over long distances, which is crucial for offshore wind projects located far from shore. However, the technology does come with challenges, particularly in terms of its uncontrollability and the need for a robust offshore network to support wind turbines (WTs). The review discusses various control strategies, both decentralized and centralized, that can be employed to enhance the performance of DRU systems.
Yu emphasizes the significance of advanced control mechanisms, stating, “For the fully-grid-forming converter, the operation principle of the P–V and Q–f power control is essential for effective management at both the OWF-DRU level and the WT level.” This insight underscores the importance of integrating sophisticated control systems to optimize energy output from offshore wind farms.
The review also addresses practical challenges, including start-up issues linked to the unidirectional power flow characteristic of DRU systems. Yu and his team explore several innovative solutions, such as using medium voltage alternative current (MVAC) umbilical cables and energy storage systems for wind turbines, to mitigate these start-up difficulties.
In addition to operational efficiencies, the research outlines the fault characteristics and protection strategies necessary for DRU-HVDC systems, which are critical for maintaining reliability in offshore environments. This aspect is particularly relevant as the energy sector increasingly looks to offshore wind as a viable source of renewable energy.
As the global push for clean energy intensifies, DRU-HVDC technology presents significant commercial opportunities. By improving the viability of offshore wind farms, this technology could lead to lower energy costs and greater energy security. The findings from this review not only highlight the technical advancements in power transmission but also point to future research directions that could further enhance the effectiveness of DRU-HVDC systems.
In summary, the work by Lujie Yu and his colleagues at Tianjin University sheds light on the promising role of DRU-HVDC in the offshore wind sector, paving the way for more reliable and efficient energy transmission solutions. This research is a critical step toward realizing the full potential of offshore wind power, as discussed in “IET Renewable Power Generation.”
