Power-quality harmonic analyser
A signal-analysis system for measuring harmonics, total harmonic distortion, power factor, voltage events, and waveform quality from prepared electrical recordings.
Project definition
Problem statement
Nonlinear loads and supply disturbances can distort voltage and current waveforms, while sampling errors, frequency drift, window selection, and sensor scaling affect the calculated result.
The engineering problem is to implement traceable digital measurements for harmonics and common power-quality events and verify them against signals with known components.
Project objectives
- Validate sampled voltage and current data, units, sensor scaling, and timing.
- Estimate fundamental frequency, RMS values, phase, active power, reactive power, and power factor.
- Measure individual harmonics and total harmonic distortion under documented windowing rules.
- Detect prepared sag, swell, interruption, transient, and imbalance events where supported.
- Compare calculated values with analytical and generated reference waveforms.
System design
System modules
Waveform manager
Imports sampled channels and records sample rate, scaling, phase mapping, source, and calibration metadata.
Cycle processor
Estimates fundamental frequency, aligns analysis windows, and calculates cycle and interval summaries.
Harmonic analyser
Calculates spectra, harmonic magnitudes, phases, distortion, and selected interharmonic indicators.
Power and event module
Measures RMS and power quantities and detects configured voltage and current events.
Analysis dashboard
Shows waveforms, spectra, phasors, harmonic tables, trends, events, settings, and uncertainty notes.
Methodology
System workflow
- 01Load waveform
The student selects a prepared single-phase or three-phase recording with complete sampling metadata.
- 02Validate input
Channel length, scaling, clipping, missing samples, and frequency range are checked.
- 03Measure
The analyser estimates fundamental, RMS, power, harmonics, distortion, and configured events.
- 04Inspect result
Waveform regions link directly to spectrum bins, harmonic tables, and event markers.
- 05Verify
Measured values are compared with generated reference signals and tolerance limits.
Demonstration scenario
A prepared three-phase waveform contains a fifth harmonic and a short voltage sag. The analyser displays the waveform, phasors, spectrum, harmonic table, distortion value, and sag interval. The measured values are then compared with the known generated parameters and tolerance limits.
Engineering
Technical architecture
- Web application
- Nuxt and Vue for waveform navigation, spectra, phasors, event timelines, and result export.
- Analysis API
- FastAPI for waveform jobs, configurations, measurements, events, reference tests, and exports.
- Data layer
- PostgreSQL for file metadata, channel settings, measurement intervals, aggregate results, events, and tests.
- Signal engine
- Python, NumPy, and SciPy for frequency estimation, windowing, FFT analysis, RMS, power, and event logic.
- Verification set
- Analytically generated waveforms and prepared recordings with known harmonic and event parameters.
Testing
Evaluation
Evaluation measures
- Fundamental-frequency, RMS, power, and power-factor error
- Individual harmonic magnitude and phase error
- Total harmonic distortion error against generated reference signals
- Precision and recall for prepared sag, swell, interruption, and transient events
- Sensitivity to sampling rate, window length, noise, clipping, and frequency drift
- Processing time across channel counts, sample rates, and recording lengths
System boundaries
- The project analyses offline sampled data and does not connect directly to mains electricity.
- Measurement quality depends on sensor calibration, sampling hardware, scaling, and timing metadata.
- Configured limits and event definitions must be matched to the applicable standard and installation.
- The analyser supports education and testing and is not a certified power-quality instrument.
Included
- 01Waveform upload and measurement interface
- 02Frequency, harmonic, power, and event-analysis pipeline
- 03Spectrum, phasor, trend, and event visualisations
- 04Prepared synthetic and recorded waveforms with test results
- 05Complete source code in a private GitHub repository
- 06Complete project documentation with synopsis, abstract, methodology, signal diagrams, measurement results, screenshots, and conclusion
- 07Setup and usage guide
Project record
No buyer information is collected on this page.
- Permanent project ID
- GP-EE-1CKO99D
- Catalogued
- 21 Aug 2026
- Completed
- Pending
- Verified
- Pending
- Demonstration
- Added when ready
Handover
After purchase
- 01Payment is confirmed
The project is marked unavailable and cannot be purchased again.
- 02Repository access is granted
The buyer's submitted GitHub account receives access to the private repository.
- 03The purchase record is delivered
The certification sheet is prepared from the reviewed buyer details and sent privately by email.