FCL/B: An Integrated VSC-HVDC Fault Current Limiter/Breaker

多端直流网络和网状直流电网已被输电公用事业、工业和电力公司倡导，作为一种比点对点链路更具成本效益的整合海上可再生能源的方式。国家电网的电力十年声明和欧洲电力传输系统运营商网络的十年网络发展计划以及北海国家海上电网倡议的研究都支持这一观点。为了实现这样的HVDC网络，直流断路器是必要的，以隔离故障的直流部分。不可接受的替代方案是暂时切断整个直流网络的电源，然后隔离故障部分。这是不可接受的，因为由此导致的同时失去对AC系统的供电将从根本上超过陆上网络设计限制，并且将至少导致消费者之间的严重中断。ABB主动式高压直流断路器接近所需的效率和运行速度，确实为某些情况提供了解决方案。然而，它是相当大的，特别是当考虑到它需要操作的串联100mH电感器时。它似乎也是针对5毫秒的操作时间，评论员指出需要保护频繁的更快的事件。最快的此类事件具有需要在2ms内断开动作的电流上升速率。因此，仍然需要一种更快、更小、更便宜的解决方案来实现断路器的海上位置，以允许海上风电场集成。该项目将研究集成断路器与故障限流器技术的新颖设计，从而能够实现这些尺寸、速度和成本变革目标。

Multi-terminal DC networks and meshed DC grids have been advocated by transmission utilities, industry and academe, as a potentially more cost effective means of integrating offshore renewable energy than point-to-point links. National Grid's Electricity Ten Year Statements and the European Network of Transmission System Operators for Electricity's Ten Year Network Development Plan as well as studies by The North Seas Countries' Offshore Grid Initiative all support this view.To realize such HVDC networks, DC circuit breakers are necessary to isolate faulted DC sections. The unacceptable alternative would be to temporarily de-energise the whole DC network to then allow isolation of the faulted section. This is unacceptable because the resulting simultaneous loss of supply to the AC system would radically exceed onshore network design limits and would lead at least to severe disruption among consumers. For larger DC grids and power loss it would even cause widespread black-outs.ABBs proactive HVDC circuit breaker comes close to the required efficiency and operational speed and indeed provides a solution for some cases. However it is fairly large, especially when the series 100mH inductor it requires to operate is considered. It is also appears to be targeted at a 5ms operating time, and commentators have indicated the need for protection against frequent faster events. The fastest such events have a rate of rise of current that requires breaking action in 2ms. A faster, smaller, cheaper solution is therefore still needed to enable offshore location of circuit breakers to allow offshore wind park integration.This project will investigate novel designs integrating the circuit breaker with fault current limiter technology, which may thus be capable of achieving these size, speed and cost transformative targets.