An improved control method for cascaded multilevel inverters based on sliding mode control technique

This research proposed a control approach for the cascaded multilevel inverters based on the sliding mode control technique. The sliding mode controller has been explored to replace the traditional carrier modulation methods in the tracking control of an inverter system. The nonlinear switching law, with a smoothly nonlinear function, is applied into a sliding mode controller to reduce the chattering phenomenon caused by rapidly changing and highly amplitude of inverters current and load voltage. In addition, the sliding mode control algorithm is also designed by applying the Lyapunov theorem so that the tracking control and stability of inverters control system are guaranteed. The comparative simulation and experimental results show the effectiveness of the proposed method in consideration of the tracking control, the common mode voltages, the switching frequency, and the harmonic components.