Application of Sliding Mode Control for Half-Bridge DC/DC Converter

According to the demands of air plasma cutting power supply using a half-bridge DC/DC converter, sliding mode control (SMC) is introduced. Different from the traditional control algorithms, SMC can solve the problem of load mutation and system nonlinear effectively during the cutting process. In this paper, half-bridge indirect SMC is adopted, and then the control algorithm based on the average state space model is deduced theoretically. The simulation results show that SMC is better than PID control in improving dynamic performance. Finally, a 15kW/20kHz air plasma cutting power supply is developed, and experiment results prove the validity of the control algorithm.