Electrical Power Transformer we can see everywhere on our neighboring street. It has an important role in our daily life. Our home equipment can operate with the high voltage that we generate in the Power Station. This is the only piece of equipment in the substation that steps down the voltage level from high voltage. In this post, we will learn, “Transformer – How It’s Made?”
Transformer- How It’s Made?
Generally, transformer manufacturers start to make a transformer with two materials. The first one is paper and it is always coated with epoxy glue. The worker tapes this paper with a wooden block. The second material is a 3mm thickness aluminum strip. These metal strips withstand the heat and high voltage current produced. Then worker secured both materials with the same wooden block and rotated it. By this rotation paper and metal strips become together.
After that, an aluminum Bus Bar is called the low-voltage lead and it sends the low-voltage current out of the transformer. Then worker folds the leads and sends them to another rotating block for further wrapping. The insulation paper has epoxy glue on both sides and it is essential for the next wrapping. Because this epoxy glue will melt during the baking section and make a bond with several components.
On the new block a worker tapes on more epoxy glue insulating paper. Then they tape epoxy-coated copper wire. Workers roll on a layer of copper wire covering the insulating paper. They repeat the same process again to form a second layer of copper wire. After that worker joins the high-voltage leads with the copper wire by soldering. Then he rolls another layer of copper wire.
After that worker attached what’s called leads wire out. The wire that will protrude from the power transformer cylinder and the vinyl-coated wires will have two different voltages out of the transformer. Till now they have been making the coil for a transformer. It also has another important part called the core. Workers use electrical steel to make its core. After that, they secure the core and coil by metal strapping. This strapping will keep these two parts together in the transformer tank.
After strapping worker sends the complete assembly to the oven. Oven temperatures maintain 135-degree calculus. It will be baked for the next eight hours to remove any trace of humidity and improve the insulation. This baking also fused the epoxy glue with insulation paper, aluminum strips, and copper wire. Then complete assembly goes into the transformer tank. You can say it is the outer shell of a transformer.
Then worker attached the rubber gasket with the round edge of the tank with a hammer. Because this tank needs to be completely water resistant. Then the bolt the grounding wire with the tank. After that, they insert three thermoplastic bushings. Then they connect the low-voltage leads with the thermoplastic bushings. After that, they bolt the bushings to the tank. They also add a transformer oil-filled guide with the side of the tank. Then they position the automated transformer oil-filled machine at the top of the tank. This machine will create the vacuum pressure to remove air during oil filling.
This oil is used for transformer insulating and cooling purposes. They also attached an internal fault detector to alert the maintenance crews if there is any short circuit. The worker inserts a lead wire through the incoming thermoplastic bushings and secures it in place. Then they attached the high voltage cable connector with it. After that, they bolt the tank cover. Now before the transformer goes to service it needs to pass the testing department. They test each unit of transformer by simulation with actual power. When it passes then it’s ready to hang with your nearby utility pole.