Design and Optimization of a 200-kW Medium-Frequency Transformer for Medium-Voltage SiC PV Inverters
Design and Optimization of a 200-kW Medium-Frequency Transformer for Medium-Voltage SiC PV Inverters
复制标题
用于中压 SiC 光伏逆变器的 200 kW 中频变压器的设计与优化
DOI：
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发表时间：
2021
影响因子：
6.7
通讯作者：
A. Huang
中科院分区：
文献类型：
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作者：
Zhicheng Guo;Ruiyang Yu;Wei Xu;Xianyong Feng;A. Huang
本文提出了一种基于低损耗磁芯（FINEMET FT-3TL）的200kw中频变压器（MFT）的设计和优化方法。本文提出的优化设计方法包括预设计、初步设计和优化设计。在初步设计中，为了提高载流能力，减小漏感，选择了并联同心绕组结构。基于并联同心绕组的概念，提出了一种新型的三维打印筒子的冷却和绝缘结构。优化设计的MFT样机功率密度高于19.23 kW/L。在12kv交流峰值电压下对电气绝缘系统进行了测试。此外，在7.5 kV交流峰值电压下进行局部放电（PD）试验，确保无局部放电设计。高频双极脉宽调制电压绝缘（PD）测试首次应用于MFT的设计和测试过程中。最后，将该变压器应用于额定功率200kw的双有源桥式（DAB）变换器中。DAB变换器的峰值效率为99.53%，200 kW时的效率为98.85%。MFT的峰值效率为99.844%，200 kW时效率为99.842%。
This article presents a design and optimization methodology for a 200-kW medium-frequency transformer (MFT) based on low-loss magnetic core (FINEMET FT-3TL). The proposed optimal design methodology consists of predesign, preliminary design, and optimal design. In the preliminary design, the parallel-concentric winding structure is selected to increase the current carrying capability and reduce the leakage inductance. Based on the parallel-concentric winding concept, a novel cooing and insulation structure with 3-D printed bobbins are proposed. The optimal designed MFT prototype achieves a power density higher than 19.23 kW/L. The electrical insulation system is tested at 12 kV ac peak voltage. In addition, the partial discharge (PD) test is conducted at 7.5 kV ac peak voltage to ensure the PD-free design. The high-frequency bipolar pulsewidth modulation voltage insulation (PD) test is the first time applied in MFT design and test process. Finally, the transformer is applied in a dual-active-bridge (DAB) converter with 200 kW rated power. The peak efficiency of the DAB converter is 99.53%, and the efficiency at 200 kW is 98.85%. The peak efficiency of MFT is 99.844%, and the efficiency at 200 kW is 99.842%.