Short-circuit inductance
Short-circuit inductance is the inductance when one of the primary winding or the secondary winding of the transformer is short-circuited and measured from the other winding. This value is often called informally as leakage inductance of the transformer. But the term leakage inductance which is in the electromagnetic literature is defined as an inductance caused by a magnetic flux (leakage flux) which is interlinked with one winding of a primary winding or a secondary winding and does not interlink with the other winding. So a confusion is caused by called short-circuit inductance as leakage inductance. This symbol is Lsc or Lk.
Assuming that the coupling coefficient is k, the self-inductance of the primary winding is L1, and the self-inductance of the secondary winding is L2, short-circuit inductances of the primary side and the secondary side are as follows
This short-circuit inductance value is an important parameter that determines the resonance frequency of the magnetic phase synchronous coupling in a Resonant transformer and wireless power transfer.
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