In a core type power transformer, the most common types of windings are continuous disks for high voltage and helical for low voltage.
The windings of disc type coil is complex. The turns are wound in sections or discs – the first turn is wrapped around the cylinder and the number of turns will be wound over this first turn producing a disc section whose thickness is equal to turn width. The outside turn of this section is carried over to the next position. The turns now proceed from outside to inside, the turns are first wound from inside out and the section is then turned over by hand, without turning the coil lathe. The inside turn becomes the start of the next section, and the process is repeated until the coil is finished. The complete coil finally consists of many disc sections wound from a continuous copper conductor without brazed joint. Radial spacers and washers separate the discs. Extremely skilled and experienced winders are required for this process, but there are lots of room for errors.
At VTC-GTC, we have made significant investments in automating winding machines to eliminate human errors. For example: on-line computer, the picture in the center, keeps track of the number of turns. A Robotic arm ensures the turns are aligned and tight. Tensions on in-coming copper conductors are calibrated automatically.
All this and more ensures reliability, and requires fewer technicians at a given winding station.
VTC-GTC has multiple horizontal and vertical winding machines.
(The one on the left is a horizontal winding machine, one on the extreme right is a vertical one that’s used for larger sized units)