an Entity references as follows:
The Parametric transformer (or paraformer) is a particular type of transformer. It transfers the power from primary to secondary windings not by mutual inductance coupling but by a variation of a parameter in its magnetic circuit. First described by Wanlass, et al., 1968. Assuming Faraday's law of induction, it is possible to obtain a voltage at the secondary winding terminals also thanks to a variation of the inductance, so that