Maximum power point tracking for photovoltaic systems under partial shading conditions via modified model predictive control

Abstract

In recent years different solutions for MPPT have been proposed in many papers. MPC method is considered as it is straightforward in both method and implementation. MPC method has a faster dynamic and better steady-state response. But, the dynamic and steady-state response depends on step size in the production of the reference current in MPC method. In this article, a MMPC method was used for a Cuk converter to achieve MPPT in photovoltaic systems. In the proposed method under uniform conditions, the PI controller applied to the error between the initial reference current from P&O and the actual current of the photovoltaic array. The reference current from the PI controller and the predictive current are applied to the cost function and the required switching pulses are generated. A two-stage algorithm was proposed under non-uniform conditions. IN the first stage, the algorithm sub-divides the current characteristics of the panel, and in the second stage of the algorithm, the MMPC method maintains the operating point at maximum power. The simulation and experimental results show that the proposed method has a faster dynamic response and low steady-state power ripple. The simulation and experimental results demonstrates that the MMPC method tracks the MPP more accurately and quickly than the MPC method under PSC.