面向智能配电网的电力电子变压器关键技术研究

The development of smart grid imposes high requirements on the smartness of the equipment in grid. The conventional power transformers cannot meet the demand of the compatible, optimized and renewable-energy-easily connected smart grid any more, in addition to their high weight and cost. In this condition, the high-frequency power electronic based PET (Power Electronic Transformer), which can fulfill electrical isolation, voltage transformation and reactive power compensation etc., becomes an important device. Because PET can integrate and optimize the power electronic equipment and the conventional transformers. This project plans to research the basic theories and key technologies of PET based on a three-phase 10kV-380V prototype. The research mainly focuses on modeling and analyses of multiple conversion stages contained PET, the coordinated control of the power converters in PET and high-reliability fault-tolerant operation of PET. The implementation of this project will lay a good foundation for the theory of high-efficiency and stable operation of PET. It will also provide a representative solution for integration and compatible connection of existing power converters and renewable energy generation systems. The research results will also promote the development of smart grid in terms of high-efficiency, optimization and flexibility.

智能电网的发展对电网设备智能化水平的要求不断提高，这使得传统变压器除去重量重、造价高等缺点外，也不能满足智能电网兼容、优化、便于可再生能源接入等需求。在此背景下，通过高频化方法将电气隔离、电压变换、无功补偿等功能集于一身的电力电子变压器（Power Electronic Transformer，PET）成为对传统变压器及电力电子设备进行集成优化的重要设备。本项目拟以一台10kV-380V三相PET为典型，对配电用PET的基础理论和关键技术展开研究。主要研究内容包括：含多级电能变换的PET系统建模及分析方法、PET内变流器的多目标协调控制以及PET的高可靠性内部容错运行。本项目的开展将为PET的高效稳定运行奠定理论基础，也将为智能电网中多种电力电子设备及可再生能源之间的整体集成与兼容互联提供典型的解决方案，促进智能电网向着更加高效、优化、灵活的方向发展。

智能电网的发展对配电设备的智能化水平要求不断提高，而传统变压器无源、不可灵活控制、体积大、重量重等固有缺点使得其不能适应智能电网发展的需求。在此背景下，通过高频化方法将电气隔离、电压变换、无功补偿等功能集于一身的电力电子变压器（Power Electronic Transformer，PET）成为对传统变压器及电力电子设备进行集成优化的重要设备。本项目以一台10kV-380V 三相PET 为典型，对配电用PET的基础理论和关键技术展开研究。主要研究内容包括：含多级电能变换的PET系统建模及分析方法、PET 内变流器的多目标协调控制以及PET 的高可靠性内部容错运行。本项目的各项研究内容均按申请书计划进行，并完成了10kV-380V三相PET样机的研制和10kV电网的挂网运行实验。本项目研究中的多项成果在所研制的10kV PET样机上获得实验验证，并有多项成果成功转化应用到了广东南澳岛全球首个多端柔性直流输电工程±160kV/50MW、云南电网与南网主网直流异步联网工程±350kV/1000MW柔性直流输电换流器等实际工程当中。项目执行期间负责人李子欣获得国际电气电子工程师协会电力电子协会（Institute of Electrical and Electronic Engineers Power Electronics Society，IEEE PELS）颁发的国际学术奖励1项，发表SCI检索论文2篇，EI检索论文5篇，申请国家发明专利4项，培养博士研究生1名，硕士研究生3名。