Winding structure for static electrical induction apparatus

Abstract

Winding structure for static electrical induction apparatus such as transformers, reactors, or the like. A winding assembly is disposed in a space formed between a pair of inner and outer insulation continuous walls which are disposed in a container so as to commonly include the vertical axis of the container thereby defining the space therebetween. An inner vertical coolant passage is formed between the winding assembly and the inner insulation wall and an outer vertical coolant passage is also formed between the winding assembly and the inner insulation wall. The winding assembly is composed of a plurality of coil units stacked on one another in the vertical direction with separation at predetermined intervals so as to form horizontal coolant passages between vertically adjacent ones of the coil units, the inner and outer vertical coolant passages communicating with each other through the horizontal coolant passages. A plurality of coolant flow control members are disposed in discrete relation from one another in at least selected one of the inner and outer vertical coolant passages in a manner so that a horizontal sectional area of the selected vertical coolant passage is decreased periodically at a pitch of nP along the vertical direction where n represents an integer which is not smaller than two (2) and P represents a pitch of the coil units along the vertical direction. Further, each of the coil units may be divided into at least two, inner and outer, coil sub-units disposed concentrically with each other in a common horizontal plane to thereby additionally form an intermediate vertical coolant passage between the vertically stacked inner coil sub-units and the vertically stacked outer coil sub-units. The coolant flow control members are disposed only in this intermediate vertical coolant passage to decrease periodically the horizontal sectional area thereof at the pitch of nP in the same manner as mentioned above.