The Essence of the Little Box Challenge-Part B: Hardware Demonstrators & Comparative Evaluations
The Essence of the Little Box Challenge-Part B: Hardware Demonstrators & Comparative Evaluations
复制标题
小盒子挑战的本质 - B 部分：硬件演示器
DOI：
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发表时间：
2020
期刊：
影响因子：
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通讯作者：
J. Kolar
中科院分区：
文献类型：
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作者：
D. Neumayr;D. Bortis;J. Kolar
为了加快电力电子系统的发展，以更低的实施成本实现更高的功率密度和效率，Google 和 IEEE 发起了 Google Little Box Challenge (GLBC)，旨在通过使用最新的功率半导体技术和 创新的拓扑概念。本文，即“小盒子挑战的本质”讨论的 B 部分，介绍了作者为应对这一挑战而选择的两个基于 GaN 的逆变器系统的硬件实现和新颖的控制概念：(i) Little Box 1.0 (LB 1.0)，具有两个交错桥臂的 H 桥逆变器，均采用三角电流模式 (TCM) 调制，功率密度为 8.18 kW/dm
3
（134 瓦/英寸
3
）和 96.4% 的标称效率，以及 (ii) Little Box 2.0 (LB 2.0)，一种具有单桥臂 DC/|AC| 的逆变器拓扑采用恒定频率 PWM 和后续 |AC|/AC H 桥展开器运行的降压级，其功率密度高达 14.8 kW/dm
3
（243 瓦/英寸
3
）和 97.4% 的标称效率。LB 1.0 采用最新的 GaN 功率半导体技术、整个交流周期的零电压开关 (ZVS) 以及 200 kHz-1 MHz 范围内的可变开关频率来缩小无源滤波器的尺寸，在积极参与 GLBC 的 100 多个团队中名列前 10 名。 LB 2.0 是进一步研究的结果，并考虑了从 GLBC 中吸取的经验教训，尽管采用适度的 140 kHz 恒定频率 PWM 和交流输出电流峰值附近的硬开关，但仍实现了更高的功率密度 ρ 和更高的效率 η。对于这两个实施的原型，提供了实验结果，以确认满足所有 GLBC 技术要求。实验结果包括稳态和阶跃响应波形、EMI 和接地电流测量，以及效率和工作温度测量。然后详细讨论了 LB 2.0 相对于 LB 1.0 的 ηρ 性能改进的原因。此外，还描述了其他 GLBC 决赛入围者的解决方案，然后与本文介绍的硬件原型所实现的性能进行了比较。这得出了具有普遍重要性的发现，并为超紧凑电力电子转换器的未来发展提供了关键指导。
In order to expedite the development of power electronic systems towards higher power density and efficiency at a lower cost of implementation, Google and IEEE initiated the Google Little Box Challenge (GLBC) aiming for the worldwide smallest 2 kVA/450 VDC/230 VAC single-phase PV inverter with η > 95% CEC weighted efficiency and an air-cooled case temperature of less than 60 °C by using latest power semiconductor technology and innovative topological concepts. This paper, i.e. Part B of a discussion of The Essence of the Little Box Challenge, presents the hardware implementations and novel control concepts of two GaN-based inverter systems selected by the authors to counter the challenge: (i) Little Box 1.0 (LB 1.0), a H-bridge inverter with two interleaved bridge-legs both operated with Triangular Current Mode (TCM) modulation which features a power density of 8.18 kW/dm
3
(134 W/in
3
) and a nominal efficiency of 96.4% and (ii) Little Box 2.0 (LB 2.0), an inverter topology with single bridgeleg DC/|AC| buck-stage operated with constant frequency PWM and a subsequent |AC|/AC H-bridge unfolder, which features a remarkable power density of 14.8 kW/dm
3
(243 W/in
3
) and a nominal efficiency of 97.4% Implemented using latest GaN power semiconductor technology, Zero Voltage Switching (ZVS) throughout the AC period and a variable switching frequency in the range of 200 kHz-1 MHz in order to shrink the size of filter passives, the LB 1.0 was ranked among the top 10 out of 100+ teams actively participating in the GLBC. The LB 2.0 is the result of further research and considers lessons learned from the GLBC and achieves despite moderate 140 kHz constant frequency PWM and hard-switching around the peak of the AC output current a higher power density ρ and a higher efficiency η. For both implemented prototypes experimental results are provided to confirm that all GLBC technical requirements are met. The experimental results include steady-state and step-response waveforms, EMI and ground current measurements, as well as efficiency and operating temperature measurements. The reason for the ηρ-performance improvement of LB 2.0 over LB 1.0 are then discussed in detail. Furthermore, the solutions of other GLBC finalists are described and then compared to the performance achieved with the hardware prototypes presented in this paper. This leads to findings of general importance and provides key guideline for the future development of ultracompact power electronic converters.