ABSTRACT

This paper brings an advanced class of hybrid SVPWM techniques for medium voltage drive applications with two-level inverter which employs multiple division of active vector time (MDAVT) switching sequences to reduce total harmonic distortion (THD) and switching loss. The proposed hybrid SVPWM techniques are categorised based on the principle of bus-clamping strategies. Multiple division active vector time (MDAVT) switching sequences are used in the proposed strategies. The newly developed MDAVT switching strategies produce PWM waveform for all odd and even pulse number and maintain the symmetry of the voltage waveform. This work compares different MDAVT switching sequences based on modulation index and location of the clamping position (zero vector changing angle) of a phase in a line cycle. The proposed techniques lead to the reduction in weighted total harmonic distortion of line voltage (Vwthd) as well as switching loss. The results point to the superior order of performance of the developed MDAVT sequences in the various ranges of operation of modulation index and power factor values. The superior harmonic performance and switching loss characteristics of the MDAVT PWM techniques over the conventional SVPWM is experimentally verifiedona415 V, 2 hp induction motor drive.

摘要

本文为具有两电平逆变器的中压驱动应用提供了一类先进的混合 SVPWM 技术，该技术采用多分频有源矢量时间 (MDAVT) 开关序列来减少总谐波失真 (THD) 和开关损耗。所提出的混合 SVPWM 技术是基于总线钳位策略的原理进行分类的。在所提出的策略中使用了多分割活动向量时间（MDAVT）切换序列。新开发的 MDAVT 开关策略为所有奇数和偶数脉冲产生 PWM 波形，并保持电压波形的对称性。这项工作基于调制指数和线周期中相位的钳位位置（零矢量变化角）的位置来比较不同的 MDAVT 开关序列。所提出的技术可减少线电压的加权总谐波失真 (Vwthd) 以及开关损耗。结果表明，在调制指数和功率因数值的各种操作范围内，开发的 MDAVT 序列的性能优越。MDAVT PWM 技术优于传统 SVPWM 的谐波性能和开关损耗特性在 415 V、2 hp 感应电机驱动器上得到了实验验证。