“The genius who lit the world”, “the man who invented the twentieth century”, “the patron saint of modern electricity” – all these metaphors apply to one man in the history of electrical engineering. And this man is Nikola Tesla. Nikola Tesla (1856-1943) laid foundations of modern electrical engineering by his contribution into its theory and practice. My goal in this paper is to explore the theoretical significance of Tesla’s work as the basis for modern AC engineering and discuss things that contributed to his recognition as one of the most prominent scientists in the U.S. history. I will also focus on the question of why many people would say Tesla was a mad scientist later in his life.
Nikola Tesla: Biography in Brief
Nikola Tesla was born 10 July 1856 in a Serbian family. The place of his birth was the village of Smiljan situated near Gospic – a town in Croatia that was a part of Austria-Hungary at that time. Tesla’s father was known to be a clergyman, and his mother is described as “exceptionally bright and an inventor of household and farm implements” despite being illiterate (Klooster 302). Tesla might have got his knack for prolific inventing from his ingenious mother.
Tesla, who is believed to be America’s most prominent electric engineer, studied engineering at the famous University of Graz (Austria) (Spencer 301). He is thought to have started his inventing career there. In 1882, Tesla came to Paris and was hired by Continental Edison Company. Two years later Tesla immigrated to the U.S. and got his citizenship in 1891 at the age of 35 (Klooster 302).
Picture 1. Nikola Tesla at the age of 37. Photo taken in 1893. Author: Sarony of New York
It was in 1882 that Tesla conceived of the famous induction motor that has a rotating magnetic field. From that time on, Tesla invented various devices that utilize the rotating magnetic field. In 1888, Tesla received patents for his inventions. Here it is worth mentioning that the outstanding engineer and physicist was able to completely visualize his next invention before he started working on it. All in all, Tesla is believed to have patented over 700 inventions during his lifetime (World of Invention, “Nikola Tesla”).
Tesla’s Theoretical Work and Patents
Tesla’s numerous patents and his groundbreaking theoretical work are believed to have created the basis of modern AC systems, which includes the polyphase power distribution systems, as well as the AC motor. Let us explore Tesla’s contribution to modern electrical engineering in detail.
It was not until Tesla could establish his own company named Tesla Electric Company (1887) that the outstanding inventor had been able to create what he actually wanted. Specifically, working for Tesla Electric Company he invented the first successful polyphase motor (Notable Scientists from 1900 to the Present,“Nikola Tesla”). Tesla achieved this by creating a motor that had a few wire-taped blocks surrounding the rotor. At the moment alternating current is being supplied to the incorporated wires, a rotating magnetic field is produced, and besides current to every block was a bit out of phase with the rest. The rotor’s movement is achieved as the revolving field is being followed (Klooster 305).
Practically, the significance of Tesla’s invention was that it enabled transmitting strong electrical currents over long distances. Theoretically, Tesla’s work undermined the view of Edison that there was no practical benefit from alternating current. It proved to leave behind the invention by Edison – direct current – that was restricted by local use and needed lots of electrical relay stations in order to have the current distributed throughout a large area, a city for example (Notable Scientists from 1900 to the Present,“Nikola Tesla”). Reportedly, not long before his death Edison admitted to making the biggest mistake in his lifetime in attempting to develop direct current ignoring the benefits of AC system invented by Nikola Tesla ().
The invention described above was one of key concepts of the AC power system designed by Tesla and used in modern electrical engineering. Yet, Tesla, who won the War of Currents, sold one of his polyphase motor patents to an inventor and manufacturer Westinghouse so that it became known as Westinghouse AC system (See Picture 2). It is worth mentioning that unlike his previous financiers, Westinghouse “offered Tesla a large sum for his patent rights to the polyphase induction motor as well as a royalty on power generated”. (World of Invention) All in all, Tesla had been given around 40 patents on the basis of this technology by 1891 (Notable Scientists from 1900 to the Present).
Picture 2. Westingehouse Early AC System (1887). US Patent 373035
The support by Westinghouse gave Tesla the opportunity to develop an invention that is often called his greatest achievement. It was the hydroelectric generating plant – the first in the world’s history. This invention enabled establishing the type of power system that has been used in the States and throughout the world. Actually, it was the Niagara power plant finished in 1895 that the workability of Tesla’s alternating current was successfully proved. This plant is known to distribute current to the whole of Niagara Falls, as well as Buffalo, NY (Scientists: Their Lives and Works, “Nikola Tesla”).
Tesla’s recognition as the America greatest electrical engineer was also a result of his highly successful inventions that came one after another (See Picture 3 and Table 1). Specifically, the scientist invented the induction motor by taking advantage of his rotating magnetic field concept, as well as other electrical motors; he produced new forms of transformers and generators, as well as the system for transmission of alternating current power. Then he created the Tesla coil, as well as discovered new things about wireless communication. In addition, Tesla is known to have created fluorescent lights, as well as a new kind of steam turbine. Finally, his scientific interest rested on the wireless power transmission (Encyclopedia of World Biography, “Nikola Tesla”).
Picture 3. AC dynamo invented by Nikola Tesla, used for generation of AC effectively used for transportation of electricity throughout long distances. It may be found in U.S. Patent 390
Tesla’s interest in high-frequency currents generation proved to be useful for next generations of scientists who perfected his inventions or used them as models for their own creative work. For instance, Tesla was able to build such a machine that could produce frequencies that reached 25, 000 cycles per one second. Importantly, machines of this kind would become an inseparable part in radio development. It is also believed that Tesla discovered the wireless transmission principles back in 1893. His inventions contributed to the field of robotics as well. For instance, in 1898 Tesla demonstrated a model boat that was radio-controlled. It can be considered a forerunner of robots and it was undoubtedly ahead of time (World of Invention, “Nikola Tesla”).
Tesla’s induction motor was a type of motor based on AC where power is delivered to rotor through electromagnetic induction. The motors of this kind came to be widely used to build industrial drives and polyphase induction motors in particular. They are known to be robust and function without brushes (“Two-Phase Induction Motor”).
Tesla’s coil was conceived as a kind of resonant transformer circuit. It was produced near 1891 and has been used to high current, as well as low current, and electricity of high frequency alternating current. Interestingly, Tesla developed a device that was able to produce current that as higher than some other sources of discharges of high voltage – electrostatic machines. Since Tesla conducted experiments on his coil, there are various configurations of the latter: they may be formed by two (or three) coupled electric circuits – resonant ones. While today Tesla’s coil is displayed at the exhibitions for educational purposes or just for fun, it was used for medical, telegraphy and radio transmission purposes in the 1920s (Uth, “Tesla Coil”).
Table 1. Devices created by Nikola Tesla
Arc light systems
Various electromechanical devices that employ rotating magnetic fields
The Tesla coil
The induction motor
Tesla’s magnifying transmitter
Wireless electricity transfer
Devices for ionized gases
Devices for discharges of high voltage
Electronic logic gate
Predecessors of superconductivity
Hot Saint Elmo’s Fire
Various devices used for power transmission including alternating current long-distance
Electric vehicle concepts
Voltage multiplication circuitry
Electrotherapy plus Tesla currents
Phantom streaming devices
X-rays Tubes which use the Bremsstrahlung process
Devices for high voltage discharges
Tesla electrostatic field
Tesla turbines and Tesla pumps
Tesla impedance phenomena
Devices for charged particle beams
Devices for high field emission
Tesla’s dynamic theory of gravity
However, not all inventions and suggestions by Tesla were appreciated. Some were deemed so weird that Tesla was sometimes even called a mad scientist. In his book “Alien Intrview” Spencer writes about the following inventions suggested by Tesla:
Tesla offered to create a “wall of light” by doing manipulations with electromagnetic fields. It would make possible for gravity, time, matter, and travel to be altered at one’s will
Tesla wanted to create a cigar- or saucer-shaped aircraft that would be able to run without any source of fuel onboard, without engine, wings, propellers, etc.
Tesla wanted to use his inventions to talk to the representatives of other civilizations since he noticed some signals of extraterrestrial origin. Some even claim that he created a Teslascope for that very purpose (Spencer 303).
These are few weird inventions that Tesla believed could be created. However, these ideas, as well as Tesla’s unusual perceptions of reality, and his gift of producing prophecies led some of his contemporaries to think of him as a mad scientist.