This paper presents an effective sliding mode control defined on the basis of super twisting algorithm (ST-SMC) for three-phase grid-tied three-level neutral point clamped (NPC) inverters. Unlike the existing SMC techniques devoted for grid-tied NPC inverters, the proposed ST-SMC method suppresses chattering and achieves good tracking performance while maintaining the prominent features of the sliding mode control such as robustness and simple implementation. Furthermore, the proposed ST-SMC method has the ability to operate with imbalanced and deteriorated grid voltages. The steady-state and transient performances of ST-SMC with ideal, imbalanced and deteriorated grid voltages are investigated experimentally. The experimental results expose that the presented control approach offers fast transient response and achieves the grid current control with small total harmonic distortion.

本文提出了一种基于超扭曲算法 (ST-SMC) 定义的有效滑模控制，适用于三相并网三电平中性点钳位 (NPC) 逆变器。与现有的用于并网 NPC 逆变器的 SMC 技术不同，所提出的 ST-SMC 方法抑制了颤振并实现了良好的跟踪性能，同时保持了滑模控制的突出特点，如鲁棒性和简单的实现。此外，所提出的 ST-SMC 方法能够在不平衡和恶化的电网电压下运行。实验研究了具有理想、不平衡和恶化电网电压的 ST-SMC 的稳态和瞬态性能。