Taming Flicker & Heavy Reactive Loads
Arc and induction furnaces, rolling mills and crushers create severe flicker, huge reactive demand and three-phase imbalance - while oilfield pump-jack drives inject heavy harmonics. GEYA fast SVG / ASVG / AHF stabilize voltage, filter distortion and balance the load. Device ratings cover 220V to 800V; on 10kV and 35kV systems, high-side measurements coordinate compensation equipment installed on the low-voltage side.
Power Quality in Heavy Industry
From the blast furnace and EAF to rolling mills and cranes - and across oilfields and petrochemical plants, from pump-jack VFDs to soft starters and UPS systems - almost every major load in heavy industry is a harmonic source. Three problems dominate - we measure each before recommending hardware.
Severe Flicker from Furnaces
Arc and induction furnaces - most violently during the EAF melting period - swing current and reactive power wildly, causing visible flicker, voltage instability and stress on every load on the same bus.
Fix · Fast-Response SVGLarge Reactive Demand on Mills
Rolling mills and crushers draw heavy reactive power, wasting transformer capacity and triggering utility power-factor penalties.
Fix · SVGThree-Phase Imbalance & Harmonics
Uneven heavy loads and drive harmonics overload the neutral, heat equipment, distort the waveform and interfere with the automation and communication systems that run the plant.
Fix · ASVG
High-Speed Reactive Power, Flicker Under Control
Arc furnaces swing reactive power violently. A fast GY-SVG-PLUS responds in under 10 ms to suppress flicker and hold voltage, while a GY-ASVG adds harmonic and imbalance compensation for mixed mill loads. On 10kV / 35kV systems, high-side sampling with low-side compensation corrects the high side without a medium-voltage cabinet.
- GY-SVG-PLUS: <10 ms, continuous bidirectional reactive, no resonance
- High-side sampling / low-side compensation for 10kV / 35kV
- GY-ASVG: reactive + 2nd-50th harmonic + imbalance in one cabinet
- Unbalance after compensation ≤5%
- Meets grid power-factor assessment thresholds (typically ≥0.95) - adjustment charges end
Oil, Gas & Chemical Plants
The same measure-first method, applied to oil extraction, refining and coal-chemical processing: ride through voltage sags, filter drive harmonics and regulate lighting voltage - proven at scale across major oilfield operations.
Voltage Sags, Ridden Through in Under 3 ms
In a petrochemical plant a momentary dip on the incoming supply is all it takes: the VFDs driving lubricating-oil pumps, liquid-oxygen pumps and circulating pumps slow down, and the unit trips offline. A GEYA low-voltage ride-through (LVRT) system feeds the drive's DC bus straight through the disturbance, then hands back to the grid automatically once the supply recovers - a changeover of no more than 3 ms, so the process never notices.
- Response under 3 ms - from the sag starting to rated voltage restored at the drive
- 10 s of continuous compensation with all three phases collapsed to 0 V
- Maintenance-free high-discharge-rate lead-acid storage: 5+ year design life, 30 s stored energy
- Isolated input; output loop carries a maintenance DC breaker, isolation diode and fuse
- Overload 1.2x for 30 s or more; efficiency above 98% on standby, under 2% loss while compensating
Stable Voltage & 15% Lighting Savings
A GY-AVC sits between the grid and the load with a series compensation transformer: it monitors the incoming voltage continuously and injects a correction the moment it drifts - stepless, with no flicker and no lights-out. At a refining-petrochemical complex, an intelligent lighting stabilizer installed ahead of the lighting feeders cut lighting energy use by more than 15% while extending lamp life.
- Stepless regulation with LCL filtering - injects no harmonics into the load
- Per-phase independent control handles severely unbalanced lighting circuits
- Soft-start, scheduled dimming by astronomical calendar, settings survive outages
- Modular design with touchscreen monitoring; RS-485 plus WiFi / GPRS options
Heavy Industry - Common Questions
Engineer-to-engineer answers to help you spec the right device for furnaces and mills.
What suppresses arc-furnace flicker?
Flicker comes from violent, fast swings in reactive power. A fast GY-SVG-PLUS tracks and counteracts those swings in under 10 ms, holding voltage steady - far quicker than step-switched capacitor banks, which cannot follow furnace dynamics.
How does an SVG compare with an SVC for a mill?
A conventional SVC may use thyristor-controlled reactors and switched capacitor banks, so its output can be continuous or stepped depending on topology. Its available reactive output falls with grid voltage, and the capacitor-reactor network requires harmonic and resonance studies. A voltage-source SVG provides symmetrical inductive and capacitive current, maintains stronger compensation during voltage dips and, in GEYA configurations, responds in under 10 ms — an advantage for rapidly fluctuating furnace and rolling-mill loads.
Can I compensate on the 10kV / 35kV side?
Yes - GEYA SVG and ASVG support high-side sampling with low-side compensation: a CT samples the 10kV / 35kV side while a low-voltage unit installs on the 400V / 800V side and indirectly corrects the high-side power factor, avoiding a medium-voltage cabinet.
My oilfield pump-jack drives keep mis-tripping - what fixes it?
Harmonic distortion from the drives is the usual cause. A 690 V GY-AHF in the low-voltage distribution room filters the 2nd-50th orders in real time. Across a fleet-scale deployment at an oilfield operation in East China, GEYA equipment brought current THD from 33.69% to 11.92% - within GB/T 14549 - and the mis-trips and shutdowns stopped.
Explore Other Industries
Different load, different fix. See how GEYA solves power quality across sectors.
Running Furnaces or Rolling Mills?
Send us your single-line diagram and load profile - our engineers will model your plant and recommend the right fast SVG, ASVG or hybrid solution.
