Inverter Fault Contribution Modeling Reference Database (v2.1)
The Inverter Fault Contribution Modeling Reference Database (v2.1) is a standardized, version-controlled repository of empirically validated and simulation-verified fault current injection characteristics for grid-forming (GFM) and grid-following (GFL) inverters under diverse fault conditions, network configurations, and control settings. It provides structured, interoperable data to support protection coordination, relay setting calculations, and short-circuit analysis in inverter-dominated microgrids and distribution systems. Designed as a template resource, it enables consistent modeling assumptions, traceable parameterization, and reproducible fault contribution quantification across engineering tools and stakeholders.
π Overview
π Key Components
π― Applications
- β Adaptive Overcurrent Relay Setting Optimization
- β Microgrid Protection Coordination Validation
- β Fault Ride-Through (FRT) Compliance Assessment
π Key Formulas
Peak Asymmetrical Fault Current (GFL)
I_{peak} = \sqrt{2} \cdot I_{rms} \cdot \left(1 + e^{-\frac{t}{\tau}}\right)
Estimates peak asymmetrical current for grid-following inverters, where Ο is the effective time constant derived from control bandwidth and filter dynamics
GFM Short-Circuit Ratio (SCR_sc)
SCR_{sc} = \frac{S_{base}}{|V_{pref}| \cdot |I_{fault,max}|}
Defines inverter short-circuit capability relative to its rated apparent power and prefault voltage; used to classify fault support level per IEEE 2800
Current Limiting Factor (CLF)
CLF = \frac{I_{fault,actual}}{I_{fault,ideal}} = \min\left(1, \frac{I_{lim}}{|I_{ref}|}\right)
Quantifies reduction in fault current due to inverter current limiting, where I_lim is the hardware/software current ceiling and I_ref is the commanded current magnitude