Comparative study of model predictive current control and voltage oriented control for PWM rectifiers

This paper presents the performance evaluation and comparisons of two different control strategies for three-phase pulse width modulation (PWM) rectifiers. The two control methods are voltage oriented control (VOC) and model based predictive current control (MPCC). VOC decomposes the grid currents into active and reactive power components and regulate them separately in synchronous frame using PI. Contrary to VOC, MPCC eliminate the use of PI for the current control. It uses a discrete-time model of the system to predict the future value of the load current for all possible voltage vectors and the one minimizing the current errors is selected. The theoretical background is described, and the advantages and disadvantages of each scheme are studied through analysis and a series of experiments. A comprehensive comparison and evaluation are implemented for the two methods from several aspects such as algorithm complexity, steady state and dynamic performances, current THD. Compared to the conventional control strategy VOC, model based predictive control (MPC) is intuitive in principle and easy to understand. Furthermore, it does not require any regulators such as PI in VOC. Simulation and experiment results prove that, MPPC can achieve similar steady state performance to VOC and the dynamic response is better.