RESEARCH INITIATION AWARD: Hybrid Power Conversion Topologies for Flexible AC Transmission Systems

电力行业正在研究灵活交流输电系统(FACT)，以提高电力系统的传输能力在维持或提高安全和质量水平的同时，改善现有基础设施。大多数研究都是关于晶闸管开关电路的使用。目前这些系统必须定制设计，基本上是由于晶闸管对自然关断的内在需求，表现为开关系统和电力系统之间的谐波相互作用。这些相互作用还没有被很好地理解。为了消除这种问题，人们提出了使用带门极关断开关的功率变流器。然而，功率半导体和功率转换器技术限制了这些器件所能达到的功率水平。这项当前的研究调查了一种混合方法，其目的是实现每种方法的最佳特征，即高功率电平和无谐波相互作用的接口。

Flexible AC Transmission Systems (FACT) are being studied by the electric utility industry for increasing the transmission capability of the existing infrastructure while maintaining or increasing security and quality levels. Most studies are concerned with the use of thyristor switched circuits. Currently these systems have to be custom designed, basically due to the thyristor's inherent need for natural turn-off, manifesting itself as harmonic interactions between the switching system and the power system. These interactions are not well understood. In order to eliminate such problems, the use of power converters with gate turn-off switches has been proposed. However, the power levels reachable with these are limited by the power semiconductor and power converter technology. This current study investigates a hybrid approach which aims to achieve the best features of each, i.e. high power level and an interface free of harmonic interaction.