A novel adaptive fuzzy-based controller design using field programmable gate arrays for grid-connected photovoltaic systems

Abstract This chapter presents a control system for a grid-interfaced photovoltaic (PV) system using an improved fuzzy logic proportional integral derivative based on echo state network (FLPID-ESN) for DC-link voltage control and antiharmonic current generation with a shunt active power filter (SAPF). The SAPF is controlled by the proposed ESN technique, which is applied to take out the fundamental weight element from the nonlinear currents and evaluate the calculated currents and accordingly generate switching signals for the SAPF system. Additionally, an FLPID adaptive feedback voltage regulator is applied to maintain the reference voltage of the DC-bus in a two-stage PV power conversion system. Incremental conductance-based maximum power point tracking is used to draw out the maximum power point from the PV system. The salient features of the proposed control scenario are better FCE, harmonic rejection ability, adaptive behavior at DC and AC terminals, and better steady-state and transient response. The proposed SAPF reference current generation method can notably improve system behavior and also mitigate the harmonics raised by nonlinear loads. The proposed reference current generation strategy is mathematically examined, and some simulation results under various load and grid-transient conditions confirm its effectiveness. The effective behavior of the FLPID-ESN control scenario is compared with recently cited work that indicates the advantage of the suggested scenario in terms of FCE and harmonic rejection. Finally, the entire system is validated on an experimental setup developed in the laboratory by utilizing field programmable gate array Xilinx platforms. In summary, total harmonic distortion of the distribution terminal currents is obtained within IEEE-519 standard limits.