This article proposes hybrid selective harmonic mitigation (SHM)-pulsewidth modulation (PWM) that is characterized by both features harmonic mitigation and elimination aimed to reduce the common-mode voltage (CMV) and to mitigate the selected nontriplen harmonics in a three-phase neutral-point-clamped (NPC) inverter. As CMV harmonic modeling only shows triplens, the specified triplens are eliminated using the selective harmonic elimination (SHE) operation to control CMV pulsewidths and consequently to mitigate CMV magnitude that appears as its root-mean-square (rms) reduction. The determined nontriplen harmonics are also mitigated using the SHM approach by the same cost function. The proposed hybrid SHM-PWM empowered by both harmonic elimination and mitigation is implemented on a three-phase NPC inverter to confirm its performance on reducing CMV through experimental and theoretical analyses. It is shown that hybrid SHM is superior over pure SHE or SHM in dealing with multiobjective system, including CMV reduction and no ntriplen harmonics mitigation.

中文翻译：

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用于三相三电平 NPC 逆变器共模电压降低的混合 SHM-PWM


本文提出了混合选择性谐波抑制（SHM）-脉宽调制（PWM），其特点是同时具有谐波抑制和消除功能，旨在降低共模电压（CMV）并减轻三相中性线中选定的非三次谐波-点钳位（NPC）逆变器。由于 CMV 谐波建模仅显示三元组，因此使用选择性谐波消除 (SHE) 操作来消除指定的三元组，以控制 CMV 脉冲宽度，从而减轻表现为均方根 (rms) 减少的 CMV 幅度。确定的非三重谐波也可以通过相同的成本函数使用 SHM 方法来减轻。所提出的混合 SHM-PWM 具有谐波消除和谐波抑制功能，在三相 NPC 逆变器上实施，通过实验和理论分析确认其降低 CMV 的性能。结果表明，混合 SHM 在处理多目标系统方面优于纯 SHE 或 SHM，包括 CMV 降低和无三重谐波抑制。