Improved saturable reactance transformer

Abstract

The invention discloses an improved saturable reactance transformer, which is provided with a main core and a pair of adjacent auxiliary cores. The auxiliary magnetic cores are provided with DC control windings which adjust the reactance of the main magnetic core bearing a secondary or output winding of the transformer. A primary winding is wound on the three magnetic cores to control the output of the voltage regulation secondary winding. In order to prevent high-voltage stress in the transformer, each control winding is divided into two or more windings, and the windings are concentrically wound on a common magnetic core so as to reduce the voltage caused by the alternating current in the primary winding. The windings on the two auxiliary cores are connected in pairs in a crossed mannerto balance the induced voltage. The transformer adopts a physical structure, and the primary winding and the control windings are started at the same position, so that the voltage difference between the end points of the control windings and the end point of the primary winding is reduced, and the voltage stress insulation applied to the transformer is reduced. Each control winding of the transformer is connected to a corresponding variable control source, so as to reduce the induction of the primary alternating current to the high stress voltages in the control windings.

Description

technical field [0001] The present invention relates generally to improved variable reactance transformers and, more particularly, to a variable reactance transformer construction which permits the use of transformers in three-phase delta configuration without stress faults. Background technique [0002] Controllable transformers which exploit the saturation effect of direct current to obtain controllable output voltage and current are known in the art, and one such transformer is disclosed in US Patent No. 5,199,072. U.S. Patent No. 3,343,074 issued September 19, 1967 to Elwood M. Brock. In this patent, a variable reactance transformer is shown with three toroidal, concentrically arranged cores carrying control, primary and secondary windings formed as toroids on the cores. Each of the two outer or auxiliary cores carries the DC winding, the center or main core carries the secondary winding, and the primary winding surrounds all three cores. The DC winding is connected in...

AI Technical Summary

Problems solved by technology

[0007] In view of the above, an object of the present invention is to devise a transformer structure capable of overcoming the difficulties encountered with existing transformer systems and allowing the use of variable reactance transformers at high loads, especially in three-phase connected the case

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