Comparative Optimization Design of a Modular Multilevel Converter Tapping Cells and a 2L-VSC for Hybrid LV ac/dc Microgrids
Comparative Optimization Design of a Modular Multilevel Converter Tapping Cells and a 2L-VSC for Hybrid LV ac/dc Microgrids
复制标题
用于混合低压交流/直流微电网的模块化多电平变流器分接单元和 2L-VSC 的比较优化设计
DOI：
10.1109/tia.2019.2897263
复制
发表时间：
2019
影响因子：
4.4
通讯作者：
T. Green
中科院分区：
文献类型：
--
作者：
A. Lachichi;A. Junyent;T. Green
本文介绍了在混合低压AC/DC微电网应用中与AC滤波器相关联的模块化多电平变换器（MMC）分接单元在效率和功率密度方面的性能，并将其与低压应用中使用的常规拓扑的性能进行比较，即，两电平电压源型变换器（2L-VSC）。因此，开发了基于遗传算法的双目标优化，提供设计LCL滤波器，MMC和2L-VSC的组件的细节。MMC达到99.4%的效率时，主直流栅极是浮动的。然而，由于其模块化和可扩展性，提供多端口连接选项，MMC分接单元具有低功率密度的缺点。从交流电网侧对MMC等效臂电感的滤波能力进行了研究，优化设计结果表明，较高的开关频率可以显著减小MMC/LCL滤波器电感元件的体积，而较高的开关频率对MMC的开关损耗影响不大。这具有减少转换器的整体占地面积和鼓励在LV应用中使用MMC的益处。
The paper presents the performance of the modular multilevel converter (MMC) tapping cells associated with an ac filter in terms of efficiency and power density in a hybrid LV ac/dc microgrid application and compares it to the performance of the conventional topology used in LV application, i.e., the two-level voltage source converter (2L-VSC). A biobjective optimization based on the Genetic Algorithm is hence developed, providing details on designing the components of the LCL filter, the MMC, and the 2L-VSC. The MMC reaches an efficiency of 99.4% when the main dc-grid is left floating. However, due to its modularity and scalability, offering multiport connections option, the MMC tapping cells has the disadvantage of low power density. Exploring the filtering capability of the equivalent arm inductance of the MMC seen from the ac grid side, optimization design results show that higher switching frequencies allow a significant volume reduction of the inductive components of the MMC/LCL filter while higher switching frequencies have little impact on the switching losses of the MMC. This has the benefit of reducing the overall footprint of the converter and encouraging the use of the MMC in LV application.