This paper proposes the independent switching technique to remove abnormal output voltage in hybrid active neutral-point clamped (ANPC) inverters. The hybrid ANPC inverter is composed by mixing silicon (Si) devices and silicon carbide (SiC) devices, unlike the conventional ANPC inverter which is generally composed of Si devices only. SiC devices provide low switching losses under a high switching frequency and a high withstand ability under high temperature compared with Si devices. Therefore, the hybrid ANPC inverter using SiC devices provides low power losses, high efficiency, and high reliability compared with the conventional ANPC inverters. In this hybrid ANPC inverter, abnormal output voltages are generated when the sinusoidal output current crosses the zero point. The abnormal output voltages are momentary pulses that must not be generated, and these pulses distort the output current and degrade the power quality. These pulses have two typical causes: one is from the switching operation time difference between switches, and the other is from deadtime. This paper proposes the independent switching technique to remove the abnormal voltages caused by the two reasons and verifies the proposed technique by simulation and experiment.

中文翻译：

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消除混合有源NPC逆变器异常输出电压的独立开关技术

本文提出了独立开关技术来消除混合有源中点钳位 (ANPC) 逆变器中的异常输出电压。混合式ANPC逆变器由硅（Si）器件和碳化硅（SiC）器件混合组成，不同于通常仅由Si器件组成的传统ANPC逆变器。与 Si 器件相比，SiC 器件在高开关频率下提供低开关损耗和在高温下的高耐受能力。因此，与传统的 ANPC 逆变器相比，使用 SiC 器件的混合 ANPC 逆变器具有低功率损耗、高效率和高可靠性。在这种混合 ANPC 逆变器中，当正弦输出电流过零点时会产生异常输出电压。异常输出电压是不能产生的瞬时脉冲，这些脉冲会使输出电流失真并降低电能质量。这些脉冲有两个典型原因：一是来自开关之间的开关操作时间差，二是来自死区时间。本文提出了独立开关技术来消除由两种原因引起的异常电压，并通过仿真和实验验证了所提出的技术。