Dsp Based Hybrid Control Method for Pv Systems

Abstract

Purpose: In this study, it is aimed to control the output voltage and current of the DC/DC boost converter faster with PI and ASM controllers, respectively, while PV panels are forced to harvest maximum power with the P&O MPPT control method. Theory and Methods: In this study, perturb and observation maximum power point tracking (P&O MPPT) control method was used to harvest maximum power from solar energy with PV panel. Conventional PI and average sliding mode (ASM) controllers were utilized for voltage and current control, respectively. The proposed hybrid control method was obtained by cascading P&O MPPT, PI, ASM controllers. MPPT and conventional PI controllers were cascaded in order to obtain an output voltage that does not change according to irradiation and load. A reference voltage was generated with MPPT for PI controller to control the output voltage. The reference current for ASMC was generated by cascaded MPPT-PI controllers. ASM controller was utilized for increasing the speed of the controller and controlling current. The process was depicted in Figure A. Results: The simulation and experimental results were compatible. There was no oscillation and chattering at output of the system. The proposed hybrid control method is quite fast. Conclusion: The simulation and experimental results clearly indicate that the proposed hybrid control method is quite satisfactory. This hybrid control method can be used for on-grid, off-grid and hybrid PV systems.