| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a variable transformer that simplifies a structure of magnetic circuit and a winding structure of a coil, approximates volume and weight to that of a transformer of an ordinary structure and does not require insulation film. SOLUTION: This variable transformer has a magnetic flux control circuit, where a primary coil 14 and a secondary coil 15 are wound on a magnetic circuit of a magnetic core 11, a window 16 is provided to a part of the magnetic core 11, and control coils 12m, 12n are wound around two sides of the window. An induced voltage is generated at the control coils 12m, 12n, but these are connected in series to cancel the induced voltage. As a result, an induced voltage will not be applied to a control circuit 13. The coil structure is similar to an ordinary single-phase transformer, except that a controllable magnetic flux control circuit consisting of the window 16 provided on the control coils 12m, 12n, control circuit 13 and magnetic core 11 is provided.</p> |
