Seite - 32 - in Nikola Tesla and the Graz Tech

32 ‘Tesla’s later struggle with the three-phase system is generally well known today. Along with his revolutionary discoveries, Tesla left Budapest for Paris in 1882, and from there he went to Strasbourg the next year and in 1884 to America, where he registered the basic three-phase current patents in 1887 and ushered in a new epoch in electrical engineering. So great was the aver- sion of the engineers and scientists of that time to alternating current and so great was the preference and the bias in favour of direct current that Tesla had to fight for more than five years to get funds to ensure victory for his new system. It is also no wonder, for Marcel Deprez carried out big experiments in 1886 to show that the problem of power transmission could only be solved using direct current. And what was the result? Five direct-current 1000-volt dynamos connected in series and a total of 200kW had to be used to transmit barely half of this energy over a distance of 15 km. ‘This appears almost improbable today because now we transmit millions of kilowatts across hundreds and even thousands of kilometres – but using Te- sla’s alternating current, which allows bigger machine units to be built and higher voltages to be run. Today, large electrical factories have no problems building enormous generators for 100,000 or more kilowatts and huge trans- formers for 220,000 volts or even 400,000 volts. Whereas at the end of the last century, according to the well- known engineer E. Egger in the E. u. M. of 1893, New York was supplied with electrical energy in 1950 by small electrical centres distributed in various parts of the city, today it is possible to cover an incomparably greater demand with a single centre. ‘Bearing these figures in mind, the importance of the three-phase system and the achievements of Tesla become clear. Equally important are the results which have been achieved in the field of high frequency and radio technology over the decades, whose foundations were laid by Tesla’s research and dis- coveries. ‘The Graz-Leoben College of Technology and Mining played a decisive role in all these results because its former student made them possible.