Towards fault-tolerant, reliable, efficient, and economical DC-DC conversion for DC grid (FREE-DC)

面向直流电网实现容错、可靠、高效且经济的 DC-DC 转换 (FREE-DC)

• 批准号: EP/X031608/1
• 负责人: Peng Li
• 金额: $ 37.69万
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX031608%2F1
• 关键词: Towards; fault; tolerant; reliable; efficient

The UK is a global leader in offshore wind energy. Its installation will be nearly quadrupled to 40 GW by 2030 according to the government plan. The Climate Change Committee (CCC) also predicts that total offshore wind may rise to 100 GW by 2050 to back the nation's net-zero goal. Such large-scale expansion and the concerted effort of other European countries to battle the climate crisis will drive the development and interconnection of offshore HVDC infrastructures within and beyond the UK into a DC transmission grid (rather than separate point-to-point transmission links) to ensure energy security and maximise economic gains. Research on planning such a DC grid has significant participation from the UK, supported by several large EU and EPSRC projects. While the multi-terminal DC grid assuming a standard voltage level for all joining terminals (likely within one planning phase) has achieved considerable progress such as on the control and DC circuit breakers, the DC-DC converters interlinking DC systems at different voltage levels face serious challenges that need to be addressed. To date, no such equipment or pilot-scale demonstration has been installed, and the reluctance is mainly due to the high cost and power losses with the existing concepts for HVDC-DC conversion. These methods based on topology-level variations often lead to a typical "Whac-A-Mole" situation among key performance indicators (i.e., cost, losses, and capability).The above difficulty stems from the characteristics of the power transistors that are used to construct HVDC converters. The proposed research will enable fundamental-level innovation by complementary use of hybrid power switches for HVDC-DC converters, which will simultaneously achieve reduced cost, lower losses, and enhanced operational flexibility. To realise the full potential of the proposed solution, this project, at first, will systematically perform modelling, design, control, and simulation studies for a new breed of DC-DC conversion architectures. Then, based on the knowledge acquired, a high-capacity test bench for the hybrid switch commutation will be built to experimentally investigate the optimisation of device hybridisation. A downscaled 900 V to 200 V, 9.6 kW DC-DC converter prototype will also be designed and integrated with a 9-converter DC grid demonstrator in the Aberdeen University lab to test its system performance. During the project, the university research and industry expertise will be combined effectively by working closely with experts from Hitachi Energy. The success of this project will set a solid foundation for new research lines in the future such as unique DC grid topologies and operational strategies enabled by the new DC-DC converters.

英国是海上风能的全球领导者。根据政府计划，到 2030 年，其装机容量将增加近四倍，达到 40 吉瓦。气候变化委员会 (CCC) 还预测，到 2050 年，海上风电总量可能会增加到 100 吉瓦，以支持国家的净零排放目标。如此大规模的扩张以及其他欧洲国家应对气候危机的共同努力将推动英国境内外海上高压直流输电基础设施的发展和互连，形成直流输电网络（而不是单独的点对点输电链路）确保能源安全并实现经济收益最大化。英国大量参与了此类直流电网规划研究，并得到了多个大型欧盟和 EPSRC 项目的支持。虽然多端直流电网对所有连接终端采用标准电压等级（可能在一个规划阶段内）已经取得了相当大的进展，例如在控制和直流断路器方面，但互连不同电压等级直流系统的直流-直流转换器面临着挑战。需要应对的严峻挑战。迄今为止，尚未安装此类设备或进行试点示范，其不愿意的主要原因是现有高压直流-直流转换概念的成本高且功率损耗高。这些基于拓扑级变化的方法往往会导致关键性能指标（即成本、损耗和能力）出现典型的“打地鼠”情况。上述困难源于所使用的功率晶体管的特性建造HVDC换流器。拟议的研究将通过补充使用 HVDC-DC 转换器的混合功率开关来实现基础层面的创新，这将同时实现降低成本、降低损耗和增强操作灵活性。为了充分发挥所提出解决方案的潜力，该项目首先将系统地对新型 DC-DC 转换架构进行建模、设计、控制和仿真研究。然后，基于所获得的知识，将建立一个用于混合开关换向的大容量测试台，以通过实验研究器件混合的优化。还将设计缩小规模的 900 V 至 200 V、9.6 kW DC-DC 转换器原型，并与阿伯丁大学实验室的 9 转换器直流电网演示器集成，以测试其系统性能。在项目期间，通过与日立能源专家的密切合作，大学研究和行业专业知识将得到有效结合。该项目的成功将为未来的新研究方向奠定坚实的基础，例如由新型直流-直流转换器实现的独特直流电网拓扑和运行策略。