A new approach to improve the power quality of medium voltage induction motor drive (MVIMD) at both utility and drive end is presented. Here, 3-multi-winding transformers (MWT) (T1, T2, T3) are utilized and each MWT converts 3-phase input AC-supply into two isolated 5-phase AC-supplies with unique (18°) phase-shift among them. Moreover, due to unique (±6° and 0°) angle in the primary sides of these MWTs, the line current drawn from the grid has 60-pulses. By applying this technology, the input current harmonics are decreased to well below the requirement of the IEEE 519 standard. This 60-pulse AC-DC converter gives 6-isolated DC-supplies, which are input of a 5-level six-leg neutral point clamped (NPC) inverter feeding an induction motor. A modified direct torque control (DTC) strategy is used in this study for 5-level six-leg NPC inverter fed induction motor drive (IMD). Because of it, this IMD has better performance than the existing IMD. The system performance is evaluated using MATLAB-Simulink software and is then experimentally verified on a prototype developed in the laboratory under all required operation of IMD to validate the performance of the system.

中文翻译：

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基于中压感应电机驱动的 60 脉冲 AC-DC 转换器馈电 5 级六腿 NPC 逆变器的无传感器 DTC 方案

提出了一种在公用事业端和驱动端改善中压感应电机驱动 (MVIMD) 电能质量的新方法。这里使用了 3 多绕组变压器 (MWT)（T1、T2、T3），每个 MWT 将 3 相输入交流电源转换为两个隔离的 5 相交流电源，它们之间具有独特的 (18°) 相移他们。此外，由于这些 MWT 的初级侧具有独特的（±6° 和 0°）角度，从电网汲取的线电流具有 60 个脉冲。通过应用该技术，输入电流谐波降低到远低于 IEEE 519 标准的要求。这种 60 脉冲 AC-DC 转换器提供 6 个隔离的直流电源，这些电源是为感应电机供电的 5 电平六桥臂中性点钳位 (NPC) 逆变器的输入。在这项研究中，改进的直接转矩控制 (DTC) 策略用于 5 级六腿 NPC 逆变器馈电感应电机驱动 (IMD)。正因为如此，这种IMD比现有的IMD具有更好的性能。系统性能使用 MATLAB-Simulink 软件进行评估，然后在实验室开发的原型上在 IMD 的所有必需操作下进行实验验证，以验证系统的性能。