Collaborative Research: Novel Modular High-density High-efficiency medium voltage power converter

合作研究：新型模块化高密度高效中压电源转换器

• 批准号: 2022397
• 负责人: Dong Dong
• 金额: $ 19.72万
• 依托单位: Virginia Polytechnic Institute and State University
• 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: 2020-09-15 至 2024-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2022397&HistoricalAwards=false
• 关键词: Collaborative; Research; Novel; Modular; density

Novel Modular High-density High-efficiency Medium-voltage Power ConverterHigh power solid-state power converter is a critical component in many applications, such as accessing renewables energy and energy storages from grid, e.g. solar, wind, and batteries and driving high power motors. Traditionally, most of such power converter are rated below 1 kilovolt or within lower voltage class for its simplicity. Recently, for further system cost reduction and efficiency improvement, industry is moving toward medium-voltage solutions, which can directly access the medium voltage grid, to save bulky transformer, cables and cost of the converter. To achieve such goal, it is desirable to develop a medium voltage high-power solid-state power converter, which is high-efficient, high power density/low volume and with ac output waveform close to an ideal sinusoidal waveform. To address such desire, the principle investigators proposed a novel modular high density medium-voltage power converter topology, namely three-level hybrid modular multilevel converter, which combines branches with cascaded modular cells and traditional three-level structure. The proposed concept leads to various topology variations for medium voltage application. In particular, the rectifier variation with diode as the three level structure can provide a significant cost and total system size saving and efficiency improvement compared to classic modular multilevel converter solution. Compared with the state of art solution, this proposed solution can reduce the converter volume/weight by up to 50% and the improve the converter efficiency by up to 30% while achieve the same voltage and current rating. In addition, thanks to the modular design, the proposed solution can also achieve high-fidelity ac output and can be scaled up to higher voltage rating for future applications without intensive engineering design rework. The low voltage and medium voltage silicon carbide devices can be used in the proposed family of topologies to leverage its switching-loss savings to synthesize high-fidelity ac output. Such modular design also means built-in system redundancy which can substantially improve system reliability. Thus, the intellectual merits of the proposed solution will make a strong impact on a broad range of medium voltage power conversion applications, like renewable energy grid-integration, subsea and offshore dc power delivery, naval medium voltage direct current power system, industrial variable speed drives, and transportation high-speed electric propulsion system. There are many fundamental control challenges and operation analysis for this topology and its variations. Through the proposed program, the detailed topology and operation analysis of the family of proposal converter topology will be performed for both unity power factor and non-unity power factor conditions. The phase-arm and phase energy balancing strategies will be explored and verified in simulation. And its benefits will be analyzed through detailed engineering design for down-selected example systems, including fault handling capability. In the end, scaled prototypes will be developed to demonstrate its innovation and benefit to industry. The unique industry consortium and Navy collaboration provided by the universities will foster a collaborative relationship among industry members, Navy R&D community, and academic researchers, which will consequently make a strong impact through this NSF research program.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.

新型模块化高密度高效中压功率转换器大功率固态功率转换器是太阳能、风能、电池等可再生能源和储能发电以及驱动大功率电机等应用中的关键部件。传统上，大多数这类功率转换器的额定电压在1千伏以下或在较低的电压等级内，因为其简单性。近年来，为了进一步降低系统成本和提高效率，工业界正在转向中压解决方案，这种解决方案可以直接接入中压电网，以节省笨重的变压器、电缆和变流器的成本。为了实现这一目标，迫切需要一种高效率、高功率密度/小体积、交流输出波形接近理想正弦波形的中压大功率固态功率变流器。针对这一需求，原理研究人员提出了一种新颖的模块化高密度中压功率变换拓扑，即三电平混合模块化多电平变流器，它将支路与级联模块单元相结合，与传统的三电平结构相结合。所提出的概念导致了中压应用的各种拓扑变化。特别是，与传统的模块化多电平变流器解决方案相比，采用二极管作为三电平结构的整流变流器可以显著节省成本和总系统尺寸，并提高效率。与现有的解决方案相比，该方案可以在相同的额定电压和电流的情况下，使变流器的体积/重量减小50%，效率提高30%。此外，由于模块化设计，建议的解决方案还可以实现高保真交流输出，并可以扩展到更高的额定电压，用于未来的应用，而无需密集的工程设计返工。低压和中压碳化硅器件可以用于所提出的拓扑系列中，以利用其节省的开关损耗来合成高保真交流输出。这种模块化设计还意味着内置系统冗余，可以显著提高系统可靠性。因此，提出的解决方案的智能优势将对广泛的中压电力转换应用产生重大影响，如可再生能源并网、海底和海上直流输电、海军中压直流电力系统、工业变速驱动和交通高速电力推进系统。对于这种拓扑及其变体，存在许多基本的控制挑战和操作分析。通过该方案，可以分别对单位功率因数和不单位功率因数两种情况下的变流器拓扑进行详细的拓扑结构和运行分析。对相臂和相能量平衡策略进行了研究，并进行了仿真验证。并将通过对选定的示例系统进行详细的工程设计，包括故障处理能力，来分析其好处。最后，将开发出规模化的原型，以展示其创新和对工业的好处。由大学提供的独特的行业联盟和海军合作将促进行业成员、海军研发社区和学术研究人员之间的合作关系，这将通过NSF的研究计划产生强大的影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

A New Hybrid Modular Multilevel Rectifier as MVac–LVdc Active Front-End Converter for Fast Charging Stations and Data Centers

• DOI: 10.1109/tpel.2023.3283469
• 发表时间: 2023-09
• 期刊: IEEE Transactions on Power Electronics
• 影响因子: 6.7
• 作者: Jian Liu;J. Motwani;R. Burgos;Zhiding Zhou;D. Dong

Hybrid Modular Multilevel Rectifier: A New High-Efficient High-Performance Rectifier Topology for HVDC Power Delivery

• DOI: 10.1109/tpel.2021.3051959
• 发表时间: 2021-01
• 期刊: IEEE Transactions on Power Electronics
• 影响因子: 6.7
• 作者: Jian Liu;D. Dong;Di Zhang

Analysis of Hybrid Modular Multilevel Rectifier Operated at Nonunity Power Factor for HVDC Applications

• DOI: 10.1109/tpel.2022.3164099
• 发表时间: 2022-09
• 期刊: IEEE Transactions on Power Electronics
• 影响因子: 6.7
• 作者: Jian Liu;Di Zhang;D. Dong

Modeling and Control Method for a Three-Level Hybrid Modular Multilevel Converter

• DOI: 10.1109/tpel.2021.3118425
• 发表时间: 2022-03
• 期刊: IEEE Transactions on Power Electronics
• 影响因子: 6.7
• 作者: Jian Liu;Di Zhang;D. Dong

A Hybrid Modular Multilevel Converter Family With Higher Power Density and Efficiency

• DOI: 10.1109/tpel.2021.3055690
• 发表时间: 2021-08
• 期刊: IEEE Transactions on Power Electronics
• 影响因子: 6.7
• 作者: Jian Liu;D. Dong;Di Zhang