兼中点电位控制的三电平逆变器SVPWM算法

SVPWM Algorithm for Three Level Inverter with Neutral Point Potential Control

为简化中点钳位型(NPC)三电平逆变器空间矢量脉宽调制(SVPWM)算法,基于虚拟作用时间提出一种可兼顾中点电位平衡控制的算法。首先,简要介绍NPC型三电平逆变器电压矢量空间;然后,详细阐述了基于虚拟作用时间的三电平SVPWM的原理及实现方法,并论证了其与传统三电平SVPWM算法的统一性。接着,基于小矢量与中点电位之间的相互作用关系,设计了一种具有可变平衡系数的中点电位控制方法。最后,通过仿真与实验,验证了所设计算法的有效性。

In order to simplify the SVPWM algorithm of NPC three-level inverters,an algorithm with neutralpoint potential balance control based on virtual operation time was proposed.Firstly,the voltage vector space of NPC three-level inverters was briefly introduced.Then,the principle and implementation method of three-level SVPWM based on virtual operation time were described in detail,and the unity of the three-level SVPWM algorithm and the traditional three-level SVPWM algorithm was demonstrated.Based on the interaction between small voltage vector and neutral point potential,a neutral point potential control method with a variable balance coefficient was designed.Finally,the effectiveness of the designed algorithm was verified by simulation and experiment.