| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To constitute a transformer, whose leakage impedance of a transformer used for an electric power system is small, in steady operation and large at short circuit troubles. <P>SOLUTION: A magnetic body 11, formed by winding excitation windings is disposed between a primary winding 2 and secondary windings 3a, 3b, and in steady operation of a transformer, a magnetic body is excited in a direction, wherein the leakage magnetic flux is demagnetized, and an excitation circuit is opened in short circuit troubles. According to this constitution, in steady operation in the transformer, leakage impedance is small, thus reducing voltage fluctuation. In short circuit troubles, leakage impedance is large, thus restraining short circuit current, and voltage fluctuation in steady operation is made small and short-circuit current in short circuit troubles is small. <P>COPYRIGHT: (C)2003,JPO</p> |
