Fault Location from COMTRADE Recordings
Upload a COMTRADE recording and get distance-to-fault estimates using three industry-standard methods — with confidence indicators and multi-loop validation.
Everything you need to locate a fault
Three Calculation Methods
Takagi, Modified Takagi, and Novosel iterative — run all three simultaneously and compare results. Each method has different strengths depending on fault type and line configuration.
Auto Fault Type Detection
Sequence component analysis automatically classifies SLG, LL, DLG, and three-phase faults, identifies the faulted phases, and selects the appropriate calculation loops.
Confidence Indicators
Each distance estimate comes with a high, medium, or low confidence rating based on method convergence, agreement between loops, and signal quality from the recording.
Multi-Loop Validation
Up to six fault loops are evaluated (AG, BG, CG, AB, BC, CA). Cross-loop agreement strengthens confidence in the final distance estimate.
Distance & Resistance Estimates
Get both the per-unit distance to fault and the estimated fault resistance. Fault resistance compensation is built into the Modified Takagi and Novosel algorithms.
Configurable Line Parameters
Enter positive-sequence (Z1) and zero-sequence (Z0) impedance in ohms or per-unit. Works for any voltage level — transmission, sub-transmission, or distribution.
The three methods
Detego implements the three most widely used impedance-based fault location algorithms. Running them in parallel lets you cross-check results and flag outliers.
Takagi method
The Takagi method is a reactance-based single-ended algorithm that uses the superimposed (delta) current to eliminate the fault resistance from the distance equation. It is well-suited for single-line-to-ground (SLG) faults and gives accurate results when fault resistance is moderate. Load current effects can introduce a small systematic error that Modified Takagi addresses.
Modified Takagi method
Modified Takagi improves on the original by compensating for pre-fault load current, which reduces the systematic error present in heavily loaded lines. It handles double-line-to-ground (DLG) and line-to-line (LL) faults more reliably and remains single-ended — no remote-end measurements required.
Novosel iterative method
Novosel uses an iterative approach that simultaneously solves for fault distance and fault resistance. By iterating until the solution converges, it achieves the highest accuracy across all fault types and is particularly robust for high fault-resistance conditions. Convergence is typically reached within a few iterations using the DFT-derived phasors from the COMTRADE recording.
Frequently asked questions
Locate your fault in seconds
Upload a COMTRADE recording, configure your line parameters, and get distance-to-fault estimates from three methods instantly.
Free to start — no account required