The LLCL filter is usually used as a switching ripple suppressor since it can attenuate switching-frequency current harmonics much better than an LCL filter using lower total inductance and capacitance. However, it is more difficult to design LLCL parameters. In addition, it has a number of initial design constraints: the fundamental reactive power, the resonant frequency fres, etc. are coupled and always contradictory, which means that designing the parameters is a Many-objective optimization problem (MaOP). The non-dominated sorting genetic algorithm-III (NSGA-III) does well in solving this kind of problem. In recent studies, the proposed methods only provide a range of parameters. Thus, obtaining certain parameters relies on experience, and using the boundary value cannot be proved optimal. However, using original NSGA-III is somewhat time-consuming for achieving specific parameters. To deal with this problem, this paper proposes a novel optimal design method for an LLCL filter based on NSGA-III with the handling of constraints. The proposed method gives a set of specific parameters and achieves a high computing efficiency. The proposed method is verified through simulations and a grid-connected inverter system based on a virtual instrument to show the effectiveness of the proposed method.

中文翻译：

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基于NSGA-III的LLCL滤波器优化设计方法

LLCL 滤波器通常用作开关纹波抑制器，因为它可以比使用较低总电感和电容的 LCL 滤波器更好地衰减开关频率电流谐波。但是，LLCL 参数的设计比较困难。此外，它有许多初始设计约束：基波无功功率、谐振频率fres等是耦合的并且总是矛盾的，这意味着设计参数是一个多目标优化问题（MaOP）。非支配排序遗传算法-III（NSGA-III）在解决此类问题方面做得很好。在最近的研究中，所提出的方法仅提供了一系列参数。因此，获得某些参数依赖于经验，不能证明使用边界值是最优的。然而，使用原始 NSGA-III 来实现特定参数有些耗时。为了解决这个问题，本文提出了一种基于 NSGA-III 的带有约束处理的 LLCL 滤波器优化设计方法。所提出的方法给出了一组特定的参数，并实现了很高的计算效率。通过仿真和基于虚拟仪器的并网逆变器系统验证了该方法的有效性。