| 摘要 |
PURPOSE:To perform an SVC 3-phase 3-winding transformer which can be used so that the neutral point of a primary winding is directly grounded, its manufacturing cost is low and its loss is low by sequentially disposing a secondary winding, a tertiary winding and a primary winding from the main leg of a core, and specifying the axial disposition of the tertiary winding. CONSTITUTION:Line terminals U, V, W are led from the center of primary windings 7, neutral point terminals 0 are led from both ends of the windings, the axial winding height of tertiary windings 12 is formed lower or higher than those of the primary and secondary windings 7, 3, and the centers of the axial heights of the windings 7, 3, 12 are formed in the same height. Thus, zero-phase impedance distribution is altered between the winding groups, the zero-phase impedance of the winding 12 can be set substantially to zero. If the zero-phase impedance to the tertiary winding becomes zero, even if the primary neutral point O is grounded to form the zero-phase impedance circuit to the primary winding and a power system, third and ninth harmonic waves of the currents are circulated in the tertiary winding, but do not flow to the primary winding, and do not flow out to the power system. |
