Power Converter Technologies for Medium Voltage Distribution Grids

电网是我们最重要的能源基础设施之一。今天，在过去一个世纪建成的电网基础设施中，可再生能源、非传统负荷和不同形式的储能系统的发电量正在快速增长。这些趋势加上升级老化电网的需求，为加拿大电网提供了一个及时的机会，使其拥有最佳的电网结构。为了适应这些变化，电网正在从传统的交流电网向更高效、更灵活的交直流混合电网发展，这种混合电网可以更好地整合可再生能源、更高效的负载和多区域系统。目前大多数交直流电网的研究要么集中在高压输电系统，要么集中在低压二次配电系统。然而，由于对中压基础设施（如电动汽车充电站、太阳能发电厂、风力发电场、公用事业规模的电池储能、城市轻轨交通和数据中心）的需求，用于中压初级配电系统的交直流电网正变得越来越重要。这些新系统的快速增长凸显了对中压直流或中压交直流系统部署的需求。在中压下，需要多电平变换器技术来弥补这一研究空白。电力电子技术对交直流电网至关重要，因为它们在交流和直流以及各种电压水平之间转换电压。在阿尔伯塔大学，我的研究小组在最先进的研究和培训设施的支持下，一直在进行电力电子和交直流电网运行方面的高影响力研究。在这项发现研究中，我将重点研究中压配电系统的多电平变换器技术。工作计划包括新的中压转换器拓扑结构，多电平转换器建模和分析方法，以及控制和脉宽调制策略。这些领域的进展将为实现交直流电网的全频谱集成提供关键环节，包括发电、输电和配电，具有最高的效率和灵活性。从传统电网向交直流智能电网的演进是世界范围内的发展趋势。该探索项目将为加拿大智能电网行业提供重要的知识和解决方案，在该项目下培训的年轻人将为该行业提供竞争优势。

The electrical grid is one of our most critical energy infrastructures. Today, the grid infrastructure built over the past century is experiencing a rapid increase in power generation from renewable sources, non-traditional loads, and different forms of energy storage systems. These trends coupled with the need to upgrade aging grids represent a timely opportunity to advance Canada's electrical grid with the best grid structures.To accommodate these changes, the power grid is evolving from a traditional AC grid to a more efficient and flexible hybrid AC-DC grid which can better integrate renewable energy sources, more efficient loads, and multi-area systems. Most AC-DC grid research today focuses on either high voltage transmission systems or low voltage secondary distribution systems. However, AC-DC grids for the medium voltage primary distribution system are becoming increasingly important because of the demand for medium voltage infrastructure such as charging stations for electrical vehicles, solar plants, wind farms, utility-scale battery energy storage, urban light-rail transportation, and data centres. The rapid growth of these new systems highlights the need for the deployment of medium voltage DC or medium voltage AC-DC systems.At medium voltage, multilevel converter technologies are needed to address this research gap. Technologies enabled by power electronics are vital to AC-DC grids because they convert voltage between AC and DC as well as various voltage levels. At UAlberta, my research group has been conducting high impact research on power electronics and AC-DC grid operation supported by state-of-the-art research and training facilities. In this Discovery research, I will focus on multilevel converter technologies for medium voltage distribution systems. The work plan includes new medium voltage converter topologies, multilevel converter modelling and analysis methods, as well as control and pulse-width-modulation strategies. Progress in these areas will provide a critical link to enable full spectrum integration of the AC-DC grid, including generation, transmission and distribution, with the highest efficiency and flexibility. The evolution from traditional electrical grids to AC-DC smart grids is a worldwide trend. This Discovery program will contribute vital knowledge and solutions to the Canadian smart grid industry and the young people trained under this program will give the industry a competitive edge.