基于GaN HEMTs的微变换单元集成型复杂电力电子装备的性能优化与容错运行方法

The contradictions between the limited characteristics and capacity of commercial power devices and the high performance and high parameter requirements in practical system applications make the converter topology of power electronic devices increasingly complicated, resulting in reduced system efficiency, power density and reliability, and limiting the development of complex power electronic devices. This project presents the concept of micro-converter unit based on GaN HEMTs. It is a high-performance integrated element with integrated converter topology, driver, protection, control and management. The complex power electronic devices can be constructed by means of a large number of series-parallel micro-converter units. Firstly, the topology and integrated design method of the GaN HEMTs based micro-converter unit are studied from the perspective of improving its efficiency and power density. After that, the coupling characteristic analysis model of large numbers of micro-converter units is established to optimize the power balance performance among the micro-converter units. And then, the multi-point fault propagation model of the coupling system is established to study the cross-response characteristics of the faults and its influence on the system stability. Finally, the redundancy design and fault-tolerant operation methods of the micro-converter unit integrated complex power electronic devices are studied from the point of view of improving the system reliability. The project will provide a standardized solution for the design of complex power electronic devices to improve system performance, and establish the theoretical and technical foundation for its wide application.

商用化功率器件有限的特性和容量与实际系统应用中高性能和高参数需求之间的矛盾使得电力电子装备的变换拓扑日益复杂，导致系统效率、功率密度和可靠性低，研发制造难度大，限制了复杂电力电子装备发展速度。本项目提出了基于GaN HEMTs的微变换单元的概念，它是一种集成了基本变换拓扑、驱动保护、底层控制和管理的处理能量的高性能集成元件，可通过大量串并联的方式构造复杂电力电子装备。首先从提高效率和功率密度的角度研究基于GaN HEMTs的微变换单元拓扑及其集成化设计方法；然后建立多微变换单元的耦合特性分析模型，优化多单元间的功率均衡性能；再建立多微变换单元耦合系统的多点故障传播模型，研究系统故障的交叉响应特性及其对稳定性的影响；最后从提高系统可靠性角度研究微变换单元集成型复杂电力电子装备的冗余设计与容错运行方法。本项目研究将为复杂电力电子装备的设计提供一种标准化方案，改善系统性能，为其广泛应用奠定基础。

商用化功率器件有限的特性和容量与实际系统应用中高性能和高参数需求之间的矛盾使得电力电子装备的变换拓扑日益复杂，导致系统效率、功率密度和可靠性低，研发制造难度大，限制了复杂电力电子装备发展速度。本项目提出了一种基于GaN HEMTs的标准拓扑，集成驱动、保护和底层控制的微变换单元（Micro-converter units, MCU），并以MCU为基本单元构建复杂的电力电子装备的方法，从变换拓扑、功率均衡方法、故障保护和容错运行等方面进行了深入的研究。提出了基于GaN HEMTs 的MCU 的标准化拓扑的优化设计原则，搭建了多个MCU测试平台，完成了软开关范围、宽电压范围和效率的综合优化设计方法的验证; 提出了易于集成在MCU 中基于多磁柱集成型耦合变压器的无源功率均衡方案和基于改进调制策略的有源功率均衡策略；建立多MCU 系统的故障响应特性模型，针对对称短路故障，提出了一种阶梯限流的短路保护策略；针对非对称短路故障，提出了一种电压源-电流源正交复合控制的保护策略；分析多个MCU 的投入退出对系统性能的影响，提出基于线圈短路和调制策略重构的MCU故障容错运行方法，提高了系统的可靠性和故障后的性能。本项目的研究成果可应用于复杂电力电子装备的标准化设计，改善系统性能，降低设计难度和成本。