Thursday, February 1, 2018

Tesla

Nicola Tesla
There is a section of land in Palo Alto which is encircled by Foothill Expressway, Arastradero, Deer Creek and Page Mill Road. In the past 40 years, there are many prominent companies reside here with their headquarters. The most prestigious one is PARC, or Palo Alto Research Center of Xerox. When time goes by, most people almost forget Xerox, but PARC, its name is still around. Perhaps it is because in mid-1970, Steve Jobs toured the center and put the PARC's graphic display and mouse into practice. It is the Macintosh personal computer. After a while, Microsoft lost little time to create Windows Operating System and it becomes the standard of the PC industry. Lately, a company called Tesla quietly moved into the Deer Creek area and set up its headquarter here.

Tesla has become a hot company these days and its name with CEO Elon Musk listed in parallel with Amazon, Google and Apple. The emergence of the industry is not just a battery car, but also a lot of communicating devices, wire or wireless which include some vehicles destine to Mars. Now the first thing we ask is why it is called Tesla. We are electrical engineers and know who Tesla is. He worked on induction motors and the alternating current (AC) transmission system. Is there any relation between Tesla & Elon Musk? It turns out very little here. The company was set up in the east coast with two founders, Martin Eberhard and Marc Tarpenning, who chose between Tesla & Faraday and finally picked Tesla. Elon Musk joined in the company later and said he preferred Edison. But Tesla was picked already, he is not going to change it easily. It is still not obvious why Tesla is chosen by the first two founders. The only thing we know is that is is just very cool to name it Tesla. Is Tesla cool? I am not sure. Tesla was a weird inventor most people knew at the time he lived. However, he was forgotten after he died. Edison seems a much more popular name to the public in the US and the world.

It is interesting to point out here that in 1891 Thomas Edison set up his lab at Menlo Park in New Jersey and now Elon Musk set up his company in Palo Alto, near Menlo Park in California. However, the name of the company is Tesla, the main rival of Edison. Here Chaos plays a big role. If Elon Musk is the first founder of the company, he would have picked up Edison as the name of the new company. The result will be great to Edison as his historical Menlo Park Laboratory in New Jersey is going to move to Menlo Park of California.

Tesla was a Serbian engineer who used to work for Edison in New York. At the time of 1890 to 1910, the need of electricity surged. The key decision at that time was to use DC or AC for long distance transmission and distribution. Edison was familiar with the DC method and thought it is much safer. Tesla thought it differently. He preferred AC technology to utilize high voltage with low current to reduce the power loss of transmission. The transformer is useful only when AC is used. Tesla left Edison to find other support and finance his endeavor. He found the Westinghouse. Eventually his AC technology was used to power the 1893 Exhibition in Chicago and proved to be successful. 

If we look at the electric car Tesla is producing now, it uses batteries, a complete DC device. However, it is inevitable, the voltage used in the car can not be a single voltage. In order to convert to other DC voltage, the AC technique must be used and rectified again to DC. No matter how we look at it, it is just not practical not to use AC technology in a DC electric car. Meanwhile it is much better to call it Electric Car instead of DC Electric Car. With this logic, we think Tesla may be cooler even Edison is a more popular name.

When we were in junior years of NTU, we studied the subject of Alternating Current. The professor was 楊進顺. He was a nice person but the way he lectured on the subject was poor at best. I am not sure he mentioned anything about Tesla at all in the class. Some of us mentioned that they don't know who Tesla is. I am not sure that is true, perhaps they just forgot what they learned before or just forgot it due to the memory loss. However, if you have chance to visit Niagara Fall in New York, you will not miss Tesla. The electric generators and the transmission system of the Niagara Fall Station uses the design of Tesla and Westinghouse. If we review the courses and subjects we studied in the first four years of EE, we will realize more than 85% of our time and effort are spent on the AC related phenomena. If everything is DC, there will be no Hertz, Induction, Laplace, Fourier, Maxwell, EM Wave, etc etc etc.

If you studied AC Circuitry and don't know Nicola Tesla, how about Steinmetz? In AC Circuitry, another prominent engineer must be mentioned along with Tesla. He is Charles Proteus Steinmetz (1865-1923), a German mathematician and electrical engineer. He came to America to avoid the prosecution at home. He went to work for a little company later purchased by GE. He showed his brilliance in the labs of GE and generated many papers on the AC circuitry. He actually worked out most of the mathematics related to AC with vector concept called Phasor. Using complex variable with rotational concept, he was able to put AC circuit on a much more rigorous basis on paper. Most of the equations and calculations in calculus becomes algebraic, a much easier to handle in the field and industry. He also made some discoveries in magnetic hysteresis that enabled engineers to design some motors for use in industry. I can't remember either 馬雲龍 or 楊進顺 have ever mentioned Steinmetz at all.

Since AC is so important in electrical engineering, we should spend some time looking into what Tesla was doing at that time. Nicola Tesla (1856-1943) was a Serbian inventor, migrated to America, served as electrical engineer, mechanical engineer, physicist and futurist. His most contribution is the design of the modern alternation current electricity supply system. He worked for a short time at Edison Machine Works in NY before moving on his own. His AC induction motor and poly-phase AC patents, licensed by Westinghouse Electric earned him some money. However, he never tried to setup his own company earnestly to make profit from what he had invented. Instead he tried to develop a series of inventions with varying degrees of success. Having spent most of his money, he lived in a series of New York hotels, leaving behind unpaid bills. The nature of his earlier work and some comments he made to the press later in life earned him the reputation of 'Mad Scientist' in American public society. Tesla died in New York City in January 1943. His work fell into relative obscurity following his death. However in 1960, the scientific circle named the SI unit of magnetic flux density the 'Tesla' in his honor. Since then, there has been a resurgence in popular interest in Tesla since early 1990.

PS: The Phasor concept is also used in the HP-35 scientific calculator in the functions of trigonometry---Sequential Table Lookup and Rotational Vector.