This study presents a hierarchical control strategy for an auxiliary power unit (APU) for aircraft to coordinate multiple power sources and control developed power electronic interfaces. The study benefits from the presence of a hybrid energy system in paralleled structure to the main generator as the complementary system. The employed structure enhances power quality and improves the voltage profile of the high-voltage DC bus. Furthermore, the developed bi-directional topology provides the possibility of interaction with the grid. Considering the APU features in an aircraft, a hierarchical control strategy with different levels of control, timescale, dynamic response, and significance are developed. The developed controller consists of a power management algorithm in the higher level, and local voltage and current controllers in the lower one. The algorithm aims to maximise the PV sub-system utilisation, overcome voltage fluctuations, increase power density, reduce operation costs, and increase system availability while allowing further development to larger systems. Simulation and experimental results confirm the robustness of the algorithm. The result shows that the proposed power sharing strategy optimises the system utilisation while achieving a high-quality voltage profile under severe fluctuations. Moreover, the stress on the battery pack is reduced to improve the life cycle and reduce operation costs.

中文翻译：

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具有双向交互能力的多源电力辅助功率单元的功率共享策略

这项研究提出了一种用于飞机的辅助动力装置（APU）的分级控制策略，以协调多个动力源并控制开发的动力电子接口。该研究得益于混合动力系统的存在，该系统与作为补充系统的主发电机具有平行结构。采用的结构提高了电能质量，并改善了高压直流母线的电压分布。此外，开发的双向拓扑提供了与网格交互的可能性。考虑到飞机的APU功能，开发了一种具有不同控制级别，时标，动态响应和重要性的分层控制策略。开发的控制器由较高级别的电源管理算法和较低级别的本地电压和电流控制器组成。该算法旨在最大程度地利用光伏子系统，克服电压波动，提高功率密度，降低运营成本，并提高系统可用性，同时允许进一步开发大型系统。仿真和实验结果证实了该算法的鲁棒性。结果表明，在剧烈波动下，提出的功率共享策略可优化系统利用率，同时获得高质量的电压曲线。而且，减小了电池组上的应力以改善寿命周期并降低运营成本。仿真和实验结果证实了该算法的鲁棒性。结果表明，在剧烈波动下，所提出的功率共享策略可优化系统利用率，同时获得高质量的电压曲线。而且，减小了电池组上的应力以改善寿命周期并降低运营成本。仿真和实验结果证实了该算法的鲁棒性。结果表明，在剧烈波动下，提出的功率共享策略可优化系统利用率，同时获得高质量的电压曲线。而且，减小了电池组上的应力以改善寿命周期并降低运营成本。