Real time Implementation of PV-Wind Hybrid System using FPGA-MPPT Controller

Abstract

A photovoltaic (PV), wind and battery-based hybrid system is proposed in this study. A PV system is implemented using mathematical analysis to improve the performance of the PV system, and a DC-DC boost converter is proposed. Different maximum power point tracking (MPPT) techniques are implemented in this paper to obtain the maximum power from the PV system. A doubly-fed induction generator (DFIG)-based wind emulator was used to design a wind energy system that could operate at all speeds. Suitable control techniques were designed for both rotor-side and grid-side converters of the DFIG system. The required reference signal for pulse width modulation (PWM) controllers is taken from the system currents and converted to two-phase coordinates, that is, direct and quadrature axis models. An IGBT-based bidirectional converter with a battery system is designed for energy storage. To maintain proper synchronization between DG systems and the grid, a PWM-based controller is implemented for a three-phase inverter, which also helps mitigate power-quality distortions. The proposed hybrid system was implemented in real-time hardware with a PV of 1 kW and a wind system of 1.5 kW. The algorithms of the MPPT techniques, such as perturb and observe (P&O) and incremental conductance (INC), were implemented in a field-programmable gate array (FPGA) controller. This study proposes a power management strategy for the proposed hybrid system using P&O and INC algorithms under different load conditions. A comparative analysis of the total harmonic distortion (THD) was performed using an current control technique in the hardware setup.