Fault Steady-State Voltage Characterization of Interconnected Island Microgrids

The substantial increase in current during faults and the injection of negative sequence components by fault ride-through strategies during asymmetrical faults significantly affect the fault steady-state voltage (FSV) of interconnected island microgrids. The complexity of system configurations, including diverse line parameters and structures exacerbates the challenges in analyzing fault voltages. This paper constructs a fault steady-state aggregation model for interconnected microgrids under fault ride-through strategy. Numerical analysis and time-domain simulations reveal that the effect of interconnection on the FSV of island microgrids adheres to a predefined structural relation independent of the interconnected system structure. This discovery provides theoretical guidance for designing cooperative protection and voltage support strategies.