Harmonic Mitigation Selector
Look up the IEEE 519 current distortion limit for your supply, and see which mitigation approaches are typically in range for a 6-pulse drive load. Guidance only.
Supply at the point of common coupling (PCC)
Load
Results
| Isc / IL ratio | – |
| IEEE 519-2022 TDD limit | – |
Typical options for this load
| Approach | Typical drive THDi | Est. TDD at PCC |
|---|
Estimate: TDD ≈ drive THDi × drive share of demand current, assuming drives at full load and negligible distortion from other loads. Typical THDi values are mid-range figures for 6-pulse drives at full load; published ranges vary widely.
How the limit is set
IEEE 519-2022 sets current distortion limits at the point of common coupling, normally the utility service, not at each drive. For systems from 120 V to 69 kV, the total demand distortion (TDD) limit depends on the ratio of the available short-circuit current (Isc) to the maximum demand load current (IL):
| Isc / IL | TDD limit |
|---|---|
| < 20 | 5.0% |
| 20 to < 50 | 8.0% |
| 50 to < 100 | 12.0% |
| 100 to < 1000 | 15.0% |
| > 1000 | 20.0% |
Individual harmonic limits also apply. Your utility or project specification may set different values. See harmonic filters and 18-pulse autotransformers for more detail.
This selector gives general guidance only and is not engineering advice or a harmonic analysis. Compliance should be confirmed by a qualified engineer using site measurements or a study, and filter performance by the manufacturer.