面向配电网的新型多端口电力电子变压器关键技术研究

为满足分布式能源的大规模接入，更加智能、灵活、互动的直流或交-直流混合电网将是未来电网的发展趋势。在此背景下，采用电力电子高频变换技术将电气隔离、电压变换、无功补偿等功能集于一身，且具有高压直流端口的电力电子变压器（Power Electronic Transformer，PET）将成为配电网中的重要设备。本项目以具有四个端口的新型PET为研究对象，对直流或交-直流混合配电网中多端口PET的基础理论和关键技术进行研究。主要研究内容包括：新型多端口PET拓扑结构及其关键参数、元件的设计与优化方法，系统功率密度和效率提升关键因素分析，基于能量平衡的高性能控制方法、冗余容错控制策略和配网中潮流的全柔性双向流动控制和优化调度策略。本项目的开展将为配网中多端口PET的高效、稳定、经济运行奠定理论基础，项目的研究成果将提升整个配电网的灵活性、可靠性和经济性。

In order to accommodate the large-scale of distributed energies, the DC or AC/DC hybrid power grid will become more intelligent, flexible and interactive. Under this background, the high-frequency power electronic technologies based PET (Power-Electronic-Transformer), which has the high voltage DC port and can fulfill electrical isolation, voltage transformation and reactive power compensation etc., becomes an important device in the distribution grid. This project plans to research the basic theories and key technologies of a four-ports PET employed in the DC or AC/DC hybrid power distribution grid. The research mainly focuses on the new topology structure of the multi-ports PET and the key parameters design and optimization, the key factor analyses for improving the system power density and efficiency, the high performance control strategies based on the energy balance concept, fault-tolerant control strategies and the fully flexible bi-directional power flow control and optimization strategies. The implementation of this project will lay a good foundation for the theory of high-efficiency, stable and economic operation of the multi-port PET employed in the distribution grid. The research results will improve the flexibility, reliability and cost-effective of the whole distribution grid.