This thesis presents a new structure for high-power hybrid rectifiers composed of a12-pulse rectifier and a Vienna rectifier. The studies include the implementation of a proper current controller such that the load is properly shared between two rectifiers. In this way, Model Predictive Control (MPC) strategy is explained and employed. Hybrid rectifiers are usually made by combining active and passive rectifiers. Using hybrid structure is a promising solution to overcome the disadvantages associated with using active and passive rectifiers. After a brief survey on different topologies of hybrid rectifiers and their control system, a new structure of hybrid rectifier is proposed and the control system of this rectifier is investigated. In this topology, the 12-pulse rectifier is used to supply the major load active power as a passive rectifier in hybrid structure. However, the 12-pulse rectifier injects distorted current into the grid with dominant 11 th and 13 th harmonics. Therefore, this rectifier cannot meet the power quality mandated by many standards such as IEEE 519. Therefore, a Vienna rectifier has been added in parallel with the 12-pulse rectifier as an active rectifier. This active rectifier compensates the harmonics injected by the passive rectifier and at the same time partially supply load active power. In this thesis, different operating region of this structure are investigated using theoretical and simulation analysis. By defining the active filtering function for the Vienna rectifier, the harmonic current components that are injected by 12-pulse rectifier into the line currents are filtered and the line current harmonic can meet the standard level of distortion that is defined for power system. In this research, the instantaneous power theory is used to generate the reference current for Vienna rectifier. The performance of the PQ theory to generate proper reference current is examined by simulation analysis. The generated reference current is realized by Vienna rectifier using the Finite Control Set Model Predictive Control (FCS-MPC) method. In this method, the current vectors are predicted for the next sampling interval and the objectives of control system are achieved by optimizing a pre-defined cost function. The optimum state of the system is defined as a state that leads to the minimum error in the cost function. The way to implementing this method is investigated and the performance of this control strategy has been reported. In the parallel structure of the proposed hybrid converters, implementation of a control strategy that can effectively share power between the parallel converters is a challenging part. In this thesis, three different strategies for controlling the power-sharing ratio between the active and passive structure in the hybrid rectifier are introduced and their effectiveness in controlling the active power processed in Vienna rectifier and 12-pulse rectifier are examined. A laboratory scale setup is implemented to evaluate the operation of proposed rectifier and verify theoretical studies. The FCS-MPC and instantaneous power theory are implemented on a digital platform using TMS320F28335 Digital Signal Processor (DSP). A method to compensate the calculation delay in the predictive control algorithm is introduced and verified. The experimental results are compared with simulation results to verify the viability of proposed method.Different practical and software optimization techniques are discussed in details. Keywords: Hybrid Rectifier, Vienna Rectifier,Instantaneous Power Theory,Finite Control Set Model Predictive Control, Active Filter,Digital Signal Processor (DSP)