Adaptive direct power control based on ANN-GWO for grid interactive renewable energy systems with an improved synchronization technique

This paper investigates the improvement of synchronization technique for single-phase inverter. Specifically, the paper proposes a modified structure of second-order generalized integrator with frequency-locked loop (SOGI-FLL) with FLL gain normalization. The proposed structure enhances the frequency detection, which makes it a powerful technique under distorted grid voltage. The validation of the proposed synchronization method includes simulations and experimental tests using Xilinx field programmable gate array (FPGA) as the target device. Moreover, time domain simulations using the direct power control (DPC) with the proposed structure are performed. The decoupled active and reactive powers are controlled using the artificial neural networks (ANNs) trained by the mean of a metaheuristic algorithm. In this paper, the grey wolf optimizer (GWO) is proposed to train the multilayer perceptron (MLP). The proposed approach shows better generation of synchronization signals and smooth power quality, making it suitable for grid-tied and microgrids (MGs) power systems control.