Optimal designing and parameter selection of voltage source inverter for real-time performance analysis in weak grid and standalone mode

In this study the grid impedance-based stability is concerned and improve the inverter stability for lower-voltage distribution networks. Also proposes the optimal filter and controller parameters for weak grids, considering IEEE std 519. The two methods are employed to enhance the inverter stability: (A). Changing the output impedance of the VSI by adjusting the grid-side inductance, (B). Optimizing the parameters for filter design and VSI controller. Ziegler-Nichols (ZN), Particle Swarm Optimization (PSO) and a real coded Genetic Algorithm (GA) are used to obtain the optimized CCL parameters to maintain the VSI stability and Total Harmonic Distortion (THD) level at the Point of Common Coupling (PCC) during the parametric uncertainty. The VSI-based system connected to the weak grid and in standalone mode is simulated on a real-time simulator, i.e., Typhoon HIL, to validate the effectiveness of obtained optimized CCL parameters by changing various conditions like filter inductance variation, grid Short Circuit Ratio (SCR), output power regulation and sudden load change in a standalone distribution network. The MATLAB/SIMULINK with m-files is utilized for the parameters optimization and controller model simulation purposes for VSI-based system. This paper presents a comprehensive review on how to choose the best inverter component parameters and their impact under different real-world conditions, whether the inverter is connected to the grid or not.