In this paper, three phase four wire five level Neutral Point Clamped Inverter (NPCI) based Static synchronous Compensator (STATCOM) is implemented for reactive power control and neutral current elimination. Three dimensional Space Vector Pulse Width Modulation (3D-SVPWM) control strategy is developed to control this 5-level NPC inverter. The behaviour of static synchronous compensator is analyzed and reactive power control is done using constant DC voltage. The objective of this compensating method is to provide balanced and sinusoidal source currents under unbalanced and nonlinear load conditions and reactive power control. The 3D-SVPWM technique provides reduced harmonic content in output voltage and current, controlled source current, minimized common mode voltage and improved output voltage. In 3D-SVPWM, switching pulses are generated with non-redundant switching states, which lead to reduce the complexity in switching time calculation and computational time is less. The highlights of the paper includes the neutral current is reduced to 0.25A, source current harmonics is minimized and it provides balanced and sinusoidal source currents with help of STATCOM compensation. The simulation and experimental results demonstrates the sinusoidal and harmonics free source current and minimized neutral current for four wire five level NPCI based STATCOM.

本文采用基于三相四线五电平中性点钳位逆变器（NPCI）的静态同步补偿器（STATCOM）进行无功功率控制和中性点电流消除。开发了三维空间矢量脉宽调制（3D-SVPWM）控制策略来控制此5级NPC逆变器。分析了静态同步补偿器的行为，并使用恒定的直流电压完成了无功功率控制。这种补偿方法的目的是在不平衡和非线性负载条件下以及无功功率控制下提供平衡和正弦的源电流。3D-SVPWM技术可降低输出电压和电流中的谐波含量，控制源电流，将共模电压降至最低，并改善输出电压。在3D-SVPWM中，产生具有非冗余切换状态的切换脉冲，这降低了切换时间计算的复杂度，并且计算时间更少。本文的重点包括中性电流降低至0.25A，使源电流谐波最小化，并借助STATCOM补偿提供平衡和正弦的源电流。仿真和实验结果证明了基于四线五电平NPCI的STATCOM的正弦和谐波自由源电流和最小化的中性电流。源电流谐波被最小化，并借助STATCOM补偿提供平衡和正弦的源电流。仿真和实验结果证明了基于四线五电平NPCI的STATCOM的正弦和谐波自由源电流和最小化的中性电流。源电流谐波被最小化，并借助STATCOM补偿提供平衡和正弦的源电流。仿真和实验结果证明了基于四线五电平NPCI的STATCOM的正弦和谐波自由源电流和最小化的中性电流。