Adjustable dc-link voltage operation is an attractive solution to improve the overall efficiency of electric vehicles (EV s ). This article proposes a dual-port inverter (DPI) with an internal dc–dc conversion system for the adjustable dc-link operation of the EV s . Unlike the conventional two-stage structure, the DPI provides a power flow path from the battery to the inverter directly. Hence, the power processed by the dc–dc converter can be reduced, resulting in higher efficiency and reduced power rating of the dc–dc converter. To fully explore the potential of this inverter in both high-speed and low-speed range, two operation modes with corresponding modulation strategies are investigated. A two-stage modulation strategy is proposed to produce undistorted current even in the presence of unevenly distributed and dynamically changing space vectors in the high-speed mode. Furthermore, the power processed by the dc–dc converter is minimized with the proposed two-stage modulation strategy, and the overall efficiency of the system is further improved. Experimental results with a 1.1-kW permanent-magnet synchronous motor are presented to validate the effectiveness of the proposed method.

中文翻译：

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具有内部DC-DC转换的双端口逆变器，用于电动汽车的可调直流链路电压操作

可调直流链路电压操作是提高电动汽车（EV）整体效率的有吸引力的解决方案 s ）。本文提出了一种双端口逆变器（DPI），带有内部dc-dc转换系统，用于EV的可调dc链接操作 s 。与传统的两级结构不同，DPI提供直接从电池到逆变器的功率流路径。因此，可以减少DC-DC转换器处理的功率，从而提高效率，并降低DC-DC转换器的额定功率。为了充分挖掘该逆变器在高速和低速范围内的潜力，研究了两种具有相应调制策略的工作模式。提出了一种二级调制策略，即使在高速模式下，即使存在空间分布不均匀且动态变化的空间矢量，也可以产生不失真的电流。此外，采用建议的两阶段调制策略可将dc-dc转换器处理的功率降至最低，从而进一步提高了系统的整体效率。实验结果以1。