Analysis of Maximum Permissible Delay-Time Limit for Stability of PV-Battery Grid-Tied System

Photovoltaic (PV) power generation is an effective means of harnessing solar energy and plays a crucial role in the operation of microgrid systems. The DC microgrid system based on PV power generation boasts the advantages of simplified control and reduced power losses. Within the microgrid, sources, storage units, and loads are connected to the DC bus via DC-DC converters while communication between modules is facilitated through a network dedicated to such purpose However, the transmission of control signals through the shared network results in time delay, rendering the microgrid a time-delay system and leading to potential instability. Therefore, it is crucial to establish the maximum permissible delay-time limit (MPDL). In this paper, the PV-battery grid-tied system is modeled, and the delay stability boundary is analyzed. Finally, we verify the MPDL stability boundary through simulation.