| 摘要 |
PURPOSE:To provide a transformer in which increase of current density at ends of windings is prevented and the temperature rise is suppressed without reducing the space factor of foil windings. CONSTITUTION:If load current flows in a low tension winding 4 and a high tension winding 5, eddy current to eliminate the horizontal component of the winding leakage flux scarcely flows at upper and lower ends of a thin metal sheet but it flows in concentration to respective upper and lower ends of an auxiliary winding 11 inside the low tension winding 4 and an auxiliary winding 11 outside the high tension winding 5. Since the upper and lower ends of the windings 4, 5, i.e. upper and lower ends of the metal sheet 7 becomes substantially flowing state of normal load current in the same manner as in the sheet intermediate portion without upper and lower ends, excessive rise of the current density at upper and lower ends of the windings 4, 5 is alleviated significantly. In this constitution, ends of the windings 4, 5 are not subjected to the abnormal temperature rise caused by increase of the current density and the winding leakage flux does not leak out of the shield installed outside the high tension winding 5, thereby overheating of a wall of the tank 1 is prevented and the tank shield becomes unnecessary. |
