Leakage Reactance
Reactance from magnetic flux not linking both windings, a major component of transformer impedance.
Leakage reactance is the reactive component of impedance from flux linking only one winding without coupling to the other. Unlike mutual flux enabling energy transfer, leakage flux creates opposing self-inductance.
Determined by winding geometry: radial spacing, axial height, turns. Dominant impedance component in large transformers. Determines voltage regulation, fault current, parallel compatibility, and short-circuit forces.
Special applications may use deliberately high leakage: furnace transformers for current limiting.
QDTB controls leakage precisely through optimized geometry for specified impedance requirements.
Related Products
Related Terms
Impedance (%Z)
Total opposition to current flow in a transformer as a percentage, determining fault current and voltage regulation.
Short-Circuit Impedance (%Zsc)
Transformer impedance measured with one winding short-circuited, determining fault current and regulation.
Winding
Coils of insulated conductors in a transformer carrying current and linking magnetic flux for energy transfer.
Fault Current
The extremely high current during a short circuit that transformers must withstand mechanically.
More Terms Starting with “L”
Load Tap Changer (LTC)
A mechanism allowing transformer tap ratio changes while energized and under load for real-time voltage regulation.
Loss Evaluation
A financial methodology assigning monetary value to transformer losses for optimal lifetime economic selection.
Lightning Impulse Test
A high-voltage test simulating lightning surges to verify transformer insulation withstands transient overvoltages.
Lightning Arrester (Surge Arrester)
A protective device diverting high-voltage surges from lightning and switching to ground, safeguarding transformer insulation.
More in “Design & Engineering”
Altitude Derating
The reduction in transformer capacity and insulation performance required at high altitudes where air density is lower.
Cooling Class (ONAN/ONAF/ODAF)
Standardized codes describing transformer cooling methods: O=Oil, N=Natural, A=Air, F=Forced, D=Directed flow.
Faraday Shield
An electrostatic shield between transformer windings blocking capacitive coupling of high-frequency noise.
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