New Sliding Mode Control of a Three-Phase AC/DC Converter with Exponential Rate Reaching Law

Abstract

This paper presents a new approach to the sliding mode control (SMC) design for a three-phase AC/DC power converter. This approach is based on the multi-input SMC design where the d-q switching functions, namely $\pmb{f_{d}}$ and $\pmb{f_{q}}$ are chosen as the control inputs. In this case, the sliding mode exists in the intersection two surfaces. This gives rise to the order reduction of the closed loop system by the number of the input. Hence, the closed loop dynamic of the converter becomes first order. This new method simplifies the control design remarkably, when compared with the conventional SMC method where the cascaded control structure is usually employed. With a proper choice of the sliding surfaces, the control performances of the converter can be determined in one shot. In order to improve the performance regarding the chattering reduction, the exponential rate reaching law (EERL) is also incorporated into this new design technique. The simulation and experimental results shows the effectiveness of the proposed technique.