Model Predictive Voltage Balance Control of Single-Phase Half-Bridge Active Front End Rectifier.

Single-phase rectifiers are one of the most practical instruments with various applications. Among them, active front-end (AFE) rectifiers are introduced with bidirectional power transfer capability for power factor correction and the elimination of current harmonics. This paper proposes an adaptive model predictive control (MPC) for a single-phase AFE rectifier. The AFE topology used in this paper is a half-bridge boost converter. This topology has higher efficiency than other single-phase AFEs due to the fewer number of active semiconductor devices. Considering the presence of one leg of capacitors in this topology, balancing the voltages of these capacitors is a challenge, along with other control objectives. Also, this paper benefits from an MPC approach by which the switching signal for every switching state is chosen such that the defined cost function is minimized in the operation state to achieve all control goals based on the predefined model of the rectifier. Furthermore, an adaptive algorithm for the inductor current estimation is presented to robustify the control system against any unwanted disturbance in the control system. As a demonstration of the superior performance of the proposed method, a 1kW rectifier setup with 700Vdc output voltage fed from a 230Vrms/50Hz grid is built in the laboratory. The applicability of the MPC controller is verified and all operation waveforms of the test setup are presented. The proposed method offers a high-quality input current with total harmonic distortion (THD) below 5% and a high-power factor (PF) close to one. Also, the efficiency is comparable with the available commercialized rectifiers. [ABSTRACT FROM AUTHOR]