Delta Operator SMC of Three-level Inverter Based on Dynamic Reaching Law

Aiming at the problem of system divergence in high-speed sampling of three-level inverter and ensuring the stability of the discrete system, a sliding mode controller based on dynamic reaching law via Delta operator discretization method for uncertain system is proposed. Firstly, Delta operator is used to discretize the three-electric plain continuous systems. Secondly, the improved Delta operator discrete reaching law based on arctangent function is used to replace the upper and lower bounds of the uncertain part of the system. Finally, the sliding mode control law of the three-level inverter is designed and the system’s stability is successfully demonstrated. The simulation results show that proposed Delta operator high-speed discretization is feasible in the three-level inverter sliding mode control system, and the discretized three-level inverter sliding mode control system is stable. The design method of Delta operator discrete reaching law control system improved by arctangent function is also correct, and it has good robustness to uncertain disturbance.