Collaborative Research: Large-Signal Stability Analysis and Enhancement of Converter-Dominated DC Microgrid

合作研究：变流器主导的直流微电网的大信号稳定性分析与增强

• 批准号: 2034812
• 负责人: Alex Huang
• 金额: $ 20万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2034812&HistoricalAwards=false
• 关键词: Collaborative; Research; Large; Signal; Stability

Title: Collaborative Research: Large-Signal Stability Analysis and Enhancement of Converter-Dominated DC MicrogridAbstract: While DC microgrids have many well-understood advantages (e.g., simpler, more efficient and compact power conversion system as well as less copper consumption in the cables), the unique DC electric characteristics, such as direct P-V coupling (i.e., even a small load/generation change can lead to voltage flickers and equipment malfunctions) and low system inertia (i.e., very little overload capacity), pose great challenges to grid stability. Small-signal stability can only ensure the stability of the system at the equilibrium point, but the true boundary of the stability domain cannot be determined; hence there are major limitations in securing stability when the system has large disturbances. Existing large-signal analysis tools in the literature have either limited applicable ranges or non-rigorous theoretical foundations. Therefore, there is an urgent need to develop a fundamental knowledge base of large-signal stability analysis in converter-dominated DC microgrids and a comprehensive design guideline for DC grid stability. The research findings of this project directly contribute to the overall goal in our country to maintain high reliability and resilience electricity with more and more microgrids and distributed energy sources. The proposed education and outreach research plan will (i) incorporate theoretical frameworks, curated data sets, and testbed from this project into the existing curriculum at both the University of Michigan-Dearborn and the University of Texas at Austin; (ii) promote K-12 students’ interest in STEM; (iii) disseminate all project materials, processes, designs and results in the public domain via public-access websites, top-ranking conference and journal publications and in diverse media; and (iv) provide rich research opportunities to under-represented undergraduates by creating societally meaningful projects on microgrids.The goal of this project is to (a) take a rigorous step toward deriving the sufficient criteria for large-signal global stability in DC microgrids with multiple distributed energy sources and constant power loads, which is still an unsolved puzzle because traditional small-signal stability analysis does not apply to converter-dominated power systems when a large disturbance occurs, such as a fault, a pulse power load, or load switching; and (b) investigate a systematic methodology to improve the global asymptotic stability of a converter-dominated DC microgrid in a theoretically sound yet easy-to-implement manner, ultimately bridging the technology gap between three traditionally disjointed areas: control theory, power systems, and power electronics. The proposed project aims to fulfill this goal by leveraging the range and depth of the PIs’ expertise (e.g., power systems, power electronics, optimization, control theory, and machine learning). The proposed research will have intellectual merits in the following areas: (1) a fundamental knowledge base to understand the large-signal stability criteria of inertia-less DC microgrids with 100% penetration of constant power loads and converter-based distributed energy sources; (2) a stability-aware converter to collectively improve the global asymptotic stability of converter-dominated DC microgrids in a theoretically sound yet easy-to-implement manner; (3) rigorous mathematical methods and safe learning algorithms for estimating the region of attraction of a general dynamic system (i.e., a DC microgrid) with multiple equilibria; and (4) a power-hardware-in-the-loop testbed allowing for dynamic interactions of the proof-of-concept prototypes of innovative stability-aware converters.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Title: Collaborative Research: Large-Signal Stability Analysis and Enhancement of Converter-Dominated DC MicrogridAbstract: While DC microgrids have many well-understand advantages (e.g., simpler, more efficient and compact power conversion system as well as less copper consumption in the cables), the unique DC electric characteristics, such as direct P-V coupling (i.e., even a small load/generation change can lead to voltage闪烁和设备故障）和低系统惯性（即，过载的容量很小）对电网稳定性构成了巨大的挑战。小信号稳定性只能确保系统在平衡点的稳定性，但是无法确定稳定域的真实边界；因此，当系统发生较大干扰时，确保稳定性存在主要局限性。文献中现有的大信号分析工具具有有限的适用范围或非鲁fim的理论基础。因此，迫切需要在转换器主导的直流微电网中建立大信号稳定性分析的基本知识基础，并针对直流电网稳定性进行全面的设计指南。该项目的研究结果直接促进了我国的总体目标，即使用越来越多的微电网和分布式能源保持高可靠性和弹性电力。拟议的教育和外展研究计划将（i）合并理论框架，精心策划的数据集，并将该项目的测试纳入密歇根大学 - 迪尔伯恩大学和德克萨斯大学奥斯汀分校的现有课程； （ii）促进K-12学生对STEM的兴趣； （iii）通过公共访问网站，顶级会议和期刊出版物以及潜水媒体在公共领域中传播所有项目材料，流程，设计和结果； （iv）通过在微电网上创建具有社会意义的项目来提供丰富的研究机会，以使代表性不足的本科生提供。该项目的目标是（a）在DC微元素中迈出足够的大量信号全球稳定性来得出足够的标准，以在DC Microgrid中具有多个分布源和不稳定性的较大的动力，因为传统能力范围是不稳定的，因为这是不稳定的努力，因为这是不稳定的努力，因为这是一个不稳定的启动，因为这是一个不稳定的动力，因为这是不稳定的，因为它是一个不稳定的动力，因为这是不稳定的，因为它是不稳定的，因为这是不稳定的，因为这是不稳定的，因为这是一个不稳定的启动，因为这是不稳定的，因为这是不稳定的，因为这是不稳定的努力。发生灾难，例如故障，脉冲功率负载或负载切换； （b）研究一种系统的方法，以一种理论声音而易于实现的方式改善转换器主导的直流微电网的全球不对称稳定性，最终弥合了三个传统上脱节的领域之间的技术差距：控制理论，电力系统和电力电子学。拟议的项目旨在通过利用范围和深度来实现这一目标。 PIS的专业知识（例如电力系统，电力电子，优化，控制理论和机器学习）。拟议的研究将在以下领域具有智力优点：（1）了解恒定功率负载和基于转换器的分布式能源的100％渗透的无惯性直流微电网的大信号稳定标准的基本知识基础； （2）一种稳定性感知的转换器，可集体以理论声音而易于实现的方式共同改善转换器主导的直流微电网的全局不对称稳定性； （3）严格的数学方法和安全学习算法，用于估计具有多个同等学分的通用动态系统（即DC微电网）的吸引力区域； （4）一个在环测试台上，允许在创新稳定性感知转换器的概念验证原型进行动态互动。该奖项反映了NSF的法定任务，并且我们是否使用基金会的知识分子优点和更广泛的影响审查标准来通过评估来诚实地支持我们的支持。

项目成果

Shared Redundancy Strategy to Improve the Reliability and Fault-Tolerant Capability of Modular Multilevel Converter

• DOI: 10.1109/tie.2022.3181416
• 发表时间: 2023-04
• 期刊: IEEE Transactions on Industrial Electronics
• 影响因子: 7.7
• 作者: Saleh Farzamkia;Houshang Salimian Rizi;A. Huang;H. Iman‐Eini