محولات العمليات الصناعية الثقيلة: أفران القوس الكهربائي (EAF) ومقومات الهيدروجين الأخضر

قوى القصر الكهروديناميكية الناتجة عن تيارات أفران القوس 100 kA، والإجهاد الحراري الدوري، والتبريد المائي OFWF، وجسور تقويم ذات إزاحة طور و24 نبضة للمحللات الكهر

1. Extreme Process Duty in Steelmaking & Hydrogen Production

Process transformers endure severe mechanical and electrical stresses far exceeding standard distribution equipment:

  • EAF Transformers: Low secondary voltage (400 - 1200 V) with massive currents up to 120 kA.
  • Green Hydrogen Electrolysers: Continuous high-current DC supplies via multi-pulse rectifiers.

2. Technical Comparison: EAF vs Hydrogen Electrolyser Transformers

ParameterElectric Arc Furnace (EAF) UnitGreen Hydrogen Rectifier Unit (PEM / Alkaline)
Secondary Current60 kA - 120 kA AC10 kA - 40 kA DC per bridge
Short-Circuit Frequency10 to 20 dead short-circuits per heatSmooth continuous DC load
Cooling MethodForced Oil-Water Heat Exchangers (OFWF)Forced Oil-Air (ONAF / OFAF)
Pulse ConfigurationDirect furnace electrodes24-Pulse (± 7.5° phase-shifted)

3. Electrodynamic Short-Circuit Force Formulation

Electrodynamic radial and axial forces on transformer windings scale with current squared (I2):

Fradial = (μ0) / (2) · ((N · Isc) / (hw))2 · 2π Rw

To withstand 120 kA short-circuit forces, EAF coils use hardened copper conductors clamped under 10 MPa hydraulic pressure.

4. 24-Pulse Harmonic Cancellation in Electrolysers

Electrolyser transformers split secondaries into four phase-shifted systems (+22.5°, +7.5°, -7.5°, -22.5°), canceling all harmonic currents up to the 23rd harmonic and achieving THD-I < 4.0%.

*Reference: IEEE Std C57.18.10-2021; IEC 61378-1:2011.*