No abstract

The studied system contains a photovoltaic conversion chain with a total power of 7.2 kW, a wind conversion chain (5.1 kW), two-level inverter related to the electrical grid through an RL filter. The control systems of the simulation model include the Model Predictive Controller (MPC), which is mainly applied for both DC/DC converters and three-phase inverter. The MPC strategy uses the mathematical model of the considered power converters in order to predict the possible future behaviors of the different controlled variables. It permits selecting the optimal voltage vector, which is able to ensure a minimization of the specified cost function. Modeling and simulation are achieved using PSIM software in order to verify the system’s performances, highlighting many scenarios of varying meteorological conditions. The simulation responses prove that the proposed MPC algorithm can offer a fast transient response, an accurate reference tracking, a high-injected power quality with a low current THD (less than 1% in the steady state).

Purpose The purpose of this paper is to propose an efficient current control technique based on model predictive control (MPC) for grid-connected wind conversion system. This nonlinear strategy is applied for the chopper circuit and grid-tied inverter and compared with other two conventional schemes; a traditional proportional-integral (PI) and sliding mode controller (SMC) using the same switching frequency. Design/methodology/approach Firstly, the MPC scheme uses the mathematical model to predict future behaviors of the controlled converter outputs for possible switching states. After that, the optimal voltage vector is selected by minimizing a cost function, which is defined as a sum of the absolute values of the controlled current errors. Then, the corresponding switching signals are applied to the converter switches in the next sampling period to track correctly the reference current. Thus, the MPC scheme ensures a minimal error between the predicted and reference trajectories of the considered variables. Findings The MPC-based algorithm presents several benefits in terms of high accuracy control, reduced DC-link voltage ripples during steady-state operation, faster transient response, lower overshoots and disturbance rejection and acceptable total harmonic distortion. Originality/value The authors introduce several simulation case studies, using PSIM software package, which prove the reliability and effectiveness of the proposed MPC scheme. Therefore, the MPC performances, during dynamic and steady-state condition, are compared with those obtained by a PI regulator and SMC to highlight the improvements, specifically the transfer of smooth power to the grid.

No abstract