Critical Clearing Time for Droop-Controlled Grid-Forming Inverters With Circular Current Limiting and Virtual Impedance Current Limiting
Xue Lyu, Wei Du, Sheik M. Mohiuddin, Yunzhi Cheng
Abstract
The critical clearing time is a crucial parameter for assessing the large-signal stability of grid-forming (GFM) inverters. Variations in current limiters can significantly impact an inverter's transient behavior during large disturbances. This letter introduces a method based on the power-angle relationship to evaluate the fault recovery of a droop-controlled GFM inverter under a three-phase bolted fault scenario, considering both the circular current limiter and the virtual impedance method. High-fidelity simulations validate the accuracy of the proposed formulas in estimating the critical clearing time of the GFM inverter
Topics & Concepts
Voltage droopInverterControl theory (sociology)Electrical impedanceCurrent limitingLimiterOutput impedanceGridTransient (computer programming)Computer sciencePower (physics)Fault (geology)Fault current limiterEngineeringElectronic engineeringVoltageElectric power systemElectrical engineeringVoltage sourceMathematicsPhysicsOperating systemArtificial intelligenceSeismologyGeologyQuantum mechanicsControl (management)GeometryMicrogrid Control and OptimizationIslanding Detection in Power SystemsHVDC Systems and Fault Protection