Transformers

Since the birth of transformers, electricity has become a commodity in modern households. For electrical companies to be able to transmit enough power to supply the market's demand in all regions, they had to produce transformers to help convey the electricity over long distances. In the early developmental stages of the alternating current induction motor, Michael Faraday discovered properties of electromagnetic induction that changed the world of power transmission forever. When the "war of the currents" came around, it was the properties that Faraday came up with that really sold alternating current as the dominant current. Further along, George Westinghouse had a key role in the development of the transformer and its use in the field. He was a main financial backing instrument that allowed Nikola Tesla to continue his research and develop a transformer system that would allow power to be sent over long distances, revolutionizing the country.

The basic function of a transformer is to take electricity from one voltage, change the voltage, and then send it on its way. Once the electricity reaches its final destination, it is to be stepped back down, and finally used in its appliance. Transformers only work with AC electricity to change voltage while holding a constant frequency. Many early scientists, such as Faraday, realized that an electric current generates a magnetic field around itself. This property is extremely important to how a transformer works. The second main property surrounding a transformer is the fact that "a changing magnetic field within a coil of wire induces a voltage across the ends of the coil". This means that if you change the current in one wire, the strength of its magnetic field also will change. In a basic transformer design, there is one core that has two coils of wire wrapped around it. The primary coil is also known as the input coil, while the output coil is known as the secondary coil. Electricity is stepped up by sending it in with fewer coils around the base than the outgoing wire. So by using alternating current the current changes the magnetic field around the primary coil, and sends it through the sedimentary to the secondary coil, carrying the electric current out. If you have more coils on the primary side, there will be more current being sent out towards the secondary wire, increasing the total voltage. The opposite holds true for stepping voltage down. The input coil has an alternating magnetic field which induces the magnetic field in the second coil, increasing the voltage on the way out. The number of coils is a direct relationship to the amount of voltage stepped up or down. The magnetic field moves in a circular motion through the core that the primary and secondary wires are wrapped around, sending the current in waves. This is in part why this current is named alternating.

There is a direct relationship between incoming alternating current, and outgoing alternating current. There is a mathematical representation of how to calculate the total amount of voltage, either increased or decreased. This law is known as Faraday's law of induction. Simply put, The secondary voltage is equal the amount of voltage coming in the primary coil multiplied by the number of turns in the secondary coil divided by the number of turns in the primary coil. Even with this law holding true, the law of conservation of energy must also hold true. Energy can neither be destroyed nor created, but it can be transformed from one type to another. Keeping this in mind, there are losses of power inside the transformers themselves. There are losses in the coils that use copper wires because materials have resistance. Voltage is equal to the amount of resistance of a material multiplied by its current. This property is known as ohms law. Wires in the transformer are often copper and do have resistance, which is one source of loss of power. The second loss is due to hysteresis, which is "the reluctance of the materials magnetic domains to reverse during each electrical cycle".

Edison's direct current would not have been sufficient for this process to work because direct current did not have an alternating current with the same properties in the magnetic field allowing the transformer to perform its function. By sending the direct current over long distances there was huge amounts of power loss during the travel. With the transformers using alternating current, it was a bit more difficult to transmit, but it would last over long distances and allow for electric current to be sent at much higher voltages. With the amount of voltage being transmitted being higher, it was possible to send enough voltage that even if it were to travel a long distance, it would still need to be stepped down in order to reach a safer level for practical use.

The transformer was not a relatively cheap experiment, but a project with no surefire profit down the road. Entrepreneur George Westinghouse, who was already wealthy from his invention of the railway air break, was the financial backing of the research team that came up with a transformer for alternating current. Westinghouse was greatly compensated for this when his company won the bid for harnessing the power of Niagara Falls. The company, including lead electrical engineer Nikola Tesla, outbid all other direct current systems for this project, and proved once and for all that alternating current was a legitimate replacement for direct current. Unless the world wanted to have a direct current station located every mile or so in densely populated areas, with many overhead electrical power lines in every city, they would need alternating current to deliver their electricity. Through every step of research, experimentation, discovery, and production, Westinghouse was the financial backing and business leader of the project. He continually was parading his progress around the United States elite, getting business and further financial aid. He knew how to work the social side of business, yet he still understood the importance of the technical side, and used his skill in both of these fields to become successful, and in turn help the transformer become a commercial product. While men like Tesla used their technical abilities to assist in the transformer, men like George Westinghouse used their charisma and business skills to keep the project in the limelight.

The transformer was a breakthrough that pushed alternating current to the forefront of the technological market. Many appliances started being produced to run off of the new AC induction motors, introduced to the world by Westinghouse Electric. The transmission of power from rural areas became an economic reality. The increased voltage allowed the power to be transmitted without loss of power because even if a thousand volts was lost throughout the transmission, it would still have to be stepped back down to two hundred and twenty volts for homes and up to four hundred and forty for businesses. The impact of this technological breakthrough helped the American market grow, moving the country as a whole forward great steps at a time. A technological advancement doesn't just help a market economy become more efficient, it actually expands the market as a whole. This new technology didn't just improve the market; it created whole new sectors and made the overall market of the United States even larger and stronger. More amenities became available to the American middle class, including an increase in the overall standard of living due to electrical comforts becoming affordable.

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