The Problem
Steel and metals operations create extreme power-quality challenges. Electric arc furnaces (EAFs) at 50–100 MW inject chaotic, broadband harmonic distortion into the plant’s electrical network. This distortion propagates downstream to every low-voltage load on site — rolling mill drives, crane VFDs, compressed air systems, cooling plants, furnace auxiliaries, and the LV distribution network that feeds them all.
What Causes It
Unlike VFDs with predictable harmonics, EAFs generate a continuously varying spectrum that changes from cycle to cycle. This distortion flows downstream through transformers to the LV distribution, where it overheats motor windings, de-rates transformers, trips sensitive automation, and inflates energy losses across every cable run. Traditional SVCs address voltage flicker at the MV bus but don’t eliminate the broadband harmonic distortion that reaches LV equipment.
Why tuned filters can’t solve this + Read more− Close
Tuned passive filters target specific harmonic orders. But the EAF spectrum is broadband and continuously varying — energy at every frequency, including interharmonics between standard orders. Passive filters also detune with temperature and ageing, and create resonance risk. Only active, software-controlled compensation can track and cancel a dynamic spectrum in real time. HarmoniQ responds in under 100 microseconds, continuously adapting.
The Solution
HarmoniQ deploys at the low-voltage (≤600V) distribution level — motor control centres, rolling mill auxiliaries, crane drives, and building services. Its narrowband tuning technology tracks and cancels the harmonic distortion that EAFs inject into the LV network, complementing existing SVC installations by addressing downstream distortion SVCs don’t reach.
A medium-voltage product (up to 14kV) is in development and will extend HarmoniQ’s reach to primary process loads including EAF supply.
Tracks and cancels the dynamic, non-characteristic harmonic spectrum of arc furnaces in real time. Reduces THD below 5% at the PCC.
Mitigates voltage flicker, reducing Pst values to within grid compliance limits. Protects rolling mill drives, caster controls, and quality instrumentation.
Dynamic PF correction tracking rapid power factor variations across the heat cycle, maintaining 0.98+ from bore-down through refining.
The Impact
| Metric | Before | After HarmoniQ | Improvement |
|---|---|---|---|
| Power factor | 0.73 | 0.98 | +34.2% |
| Voltage THD at PCC | 9.5% | 3.8% | −60% |
| Flicker Pst | 4.2 | 0.8 | −81% |
| Annual electricity cost | $44,450,000 | $37,850,000 | −$6,600,000 |
Every facility is different. Our engineers will model the exact savings, deployment costs, and timeline for your specific site — get in touch for a free, no-obligation assessment.
Beyond the Bill
Clean power extends furnace transformer life by 25–40% (replacement: $635,000+), reduces electrode consumption ($4–10/tonne), and eliminates drive trips and motor failures disrupting rolling mill production.
Annual reduction of 3,210 tonnes CO₂ supports EU CBAM competitiveness, ResponsibleSteel certification, and SBTi steel pathway targets.