NOVEL CONTROL STRATEGY FOR GRIDCONNECTED PHOTOVOLTAIC ARRAYS

PV generation systems have received much attention in recent years due to their suitable properties which offer important economic benefits. However, they are developing increasingly fast as a renewable energy resource. In this work, the configuration of PV generation systems, a dynamic model for PV modules, and their power electronic interfacing have been presented. A novel control strategy for the DCDC converter has been developed in order to extract the maximum amount of power from the PV array. Also, a novel control strategy, which is based on a d – q rotating reference frame, has been proposed for the DC-AC converter. The proposed controllers have been used to transfer the PV output power and synchronize the interfacing power converters with the AC grid. The controller designs for different operating conditions of DC-AC converter, using the average large signal model, have been presented. Based on the dynamic models, a simulation model for the PV generation systems has been developed using PSCAD/EMTDC. Simulation studies have been carried out to verify the dynamic performance of grid-connected PV systems under different operating conditions. The simulation results show that the novel control structure can transfer DC energy from the PV array, compensate the power factor of the AC grid, and improve the dynamic behavior of the grid-connected PV system. The simulation results show the effectiveness of the suggested control systems in grid-connected mode.