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

电力行业正在研究柔性交流输电系统（FACT），以提高现有基础设施的输电能力，同时保持或提高安全性质量水平。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，主要是由于可控硅固有的自然关断需求，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。为了消除这类问题，提出了采用带栅极关断开关的功率变换器。然而，这些可达到的功率水平受到功率半导体和功率转换器技术的限制。当前的研究研究了一种混合方法，旨在实现每种方法的最佳特性，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.