• Source: Short-circuit inductance

Short-circuit inductance of a real linear two-winding transformer is inductance measured across the primary or secondary winding when the other winding is short-circuited.　
The method of measuring the short circuit inductance is described in industrial standard. The industrial standard also stipulates a method for obtaining the coupling factor by combining it with the open circuit inductance value.

Measured primary and secondary short-circuit inductances may be considered as constituent parts of primary and secondary self-inductances. They are derived by using Ho-Thevenin's theorem from the equivalent inductance of the three-terminal equivalent circuit as follows. Then they are related according to the coupling factor as,





L


s
c
1



=
(
1
−

k

2


)
⋅

L


1






{\displaystyle L_{\mathrm {sc1} }=(1-k^{2})\cdot L_{\mathrm {1} }\,}






L


s
c
2



=
(
1
−

k

2


)
⋅

L


2






{\displaystyle L_{\mathrm {sc2} }=(1-k^{2})\cdot L_{\mathrm {2} }\,}


Where

k is coupling coefficient
L1 is primary self-inductance
L2 is secondary self-inductance
Short-circuit inductance measurement is used in conjunction with open-circuit inductance measurements to obtain various derived quantities like



k


{\displaystyle k}

, the inductive coupling factor and



σ


{\displaystyle \sigma }

, the inductive leakage factor.



k


{\displaystyle k}

is derived according to:




k
=


1
−



L

sc



L

oc








{\displaystyle k={\sqrt {1-{\frac {L_{\text{sc}}}{L_{\text{oc}}}}}}}


where





L

sc




{\displaystyle L_{\text{sc}}}

is the short-circuit measurement of primary or secondary inductance





L

oc




{\displaystyle L_{\text{oc}}}

is the corresponding open-circuit measurement of primary or secondary inductance
Other transformer parameters like leakage inductance and mutual inductance which cannot be directly measured may be defined in terms of k.
Short-circuit inductance is one of the parameters that determines the resonance frequency of the magnetic phase synchronous coupling in a resonant transformer and wireless power transfer. Short-circuit inductance is the main component of the current-limiting parameter in leakage transformer applications.




See also


Resonant inductive coupling




References






Notes

Kata Kunci Pencarian:

• Short-circuit inductance
• Leakage inductance
• Inductor
• Inductance
• Series and parallel circuits
• Transformer
• Henry (unit)
• Tesla coil
• Resonant inductive coupling
• Transformer types