Continuous Control Set Model Predictive Control of a Bridgeless-Boost Three-Level Active Rectifier

Over the past few decades, active rectifiers have assumed an important preponderance for numerous applications that propose to minimize power quality problems. Consequently, digital control algorithms are following this trend by contributing with a significant set of advantages. This paper presents the use of a continuous control set model predictive control (CCS-MPC) for a bridgeless-boost three-level (BB3L) active rectifier. The BB3L has a set of advantages when confronted with traditional solutions to improve power quality, where the possibility to operate with three voltage levels, sinusoidal current and unitary power factor, while using few switching devices, are the main features. Considering the multiplicity of applications for the BB3L active rectifier, the CCS-MPC is applied to obtain a robust current tracking. The BB3L is presented in detail throughout the paper and based on its mathematical model, the digital control equations are formulated, highlighting that the possibility of operating with a fixed switching frequency is the main characteristic. The results are achieved for many operating conditions, covering steady-state and transient-state, validating the accurate application of the CCS-MPC.