Sliding Modes in Three-Phase Switching Power Converters Control
A new control technique for voltage-fed and current-fed PWM three-phase converters (inverters and rectifiers) is presented. Approach is based on the application of the sliding mode design methods. A general mathematical description of the three-phase converters (buck and boost inverters and rectifiers) is developed. On the basis of this description the sliding mode controller is designed to obtain optimal PWM and desired closed-loop dynamics. Both, the PWM switching pattern and the closed-loop dynamics are addressed as a single control problem and the output of the controller provides direct commands for the converter's switches. It is shown that the same controller can be applied for all analyzed converters. The controller has a simple structure and is suitable for digital implementation. Simulation results are provided to confirm theoretical predictions.