A Robust Adaptive Control for Multi-level Inverters Based on Sliding Mode Control

This paper presents a new robust adaptive control based on Sliding Mode Control (SMC) for the cascaded H-bridge five-level inverter. The proposed method develops to modulate PWM pulses instead of using carrier waves as conventional modulation techniques. The control law of the controller improved with the nonlinear sliding-mode surface and continuous function combined with a first-order low-pass filter. Thus, the chattering phenomenon can eliminate. The control signal u(t) uses to compare with levels of comparison to generate the PWM pulse instead of the carrier waves. The Lyapunov function is applied to confirm the stability of the control system. The simulation and experimental results proved that the proposed SMC method ensures fast convergence, strong robustness, and elimination chattering. Moreover, the multi-level inverter control performance can enhance with switching frequency reduction, reduction of total harmonic distortion, Common-Mode (CM) voltage reduction, low losses, and less memory requirement.