Mikhail Osipovich Dolivo-Dobrovolsky ' onMouseout='HidePop("92461")' href="http://www.absoluteastronomy.com/topics/Gatchina">Gatchina
Gatchina is a city in Leningrad Oblast, Russia, located 45 km south of St. Petersburg by the road leading to Pskov. Population: It is part of the World Heritage Site Saint Petersburg and Related Groups of Monuments.-Early history:...
near
Saint PetersburgSaint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea. The city's other names were Petrograd and Leningrad...
— in
HeidelbergHeidelberg is a city in Baden-Württemberg, Germany. As of 2008, over 145,000 people live within the city's area. Heidelberg is a unitary authority...
,
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
), was a
RussiaRussia , officially known as both Russia and the Russian Federation , is a country in northern Eurasia . It is a semi-presidential republic, comprising 83 federal subjects...
n
engineerEngineers are concerned with developing economical and safe solutions to practical problems, by applying mathematics and scientific knowledge while considering technical constraints. The term is derived from the Latin root "ingenium," meaning "cleverness"...
,
electricianAn electrician is a tradesman specializing in electrical wiring of buildings, stationary machines and related equipment. Electricians may be employed in the installation of new electrical components or the maintenance and repair of existing electrical infrastructure...
, and
inventorAn inventor is a person who creates or discovers a new method, form, device or other useful means. The word inventor comes form the latin verb invenire, invent-, to find...
.
Mikhail Osipovich Dolivo-Dobrovolsky ' onMouseout='HidePop("92461")' href="http://www.absoluteastronomy.com/topics/Gatchina">Gatchina
Gatchina is a city in Leningrad Oblast, Russia, located 45 km south of St. Petersburg by the road leading to Pskov. Population: It is part of the World Heritage Site Saint Petersburg and Related Groups of Monuments.-Early history:...
near
Saint PetersburgSaint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea. The city's other names were Petrograd and Leningrad...
— in
HeidelbergHeidelberg is a city in Baden-Württemberg, Germany. As of 2008, over 145,000 people live within the city's area. Heidelberg is a unitary authority...
,
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
), was a
RussiaRussia , officially known as both Russia and the Russian Federation , is a country in northern Eurasia . It is a semi-presidential republic, comprising 83 federal subjects...
n
engineerEngineers are concerned with developing economical and safe solutions to practical problems, by applying mathematics and scientific knowledge while considering technical constraints. The term is derived from the Latin root "ingenium," meaning "cleverness"...
,
electricianAn electrician is a tradesman specializing in electrical wiring of buildings, stationary machines and related equipment. Electricians may be employed in the installation of new electrical components or the maintenance and repair of existing electrical infrastructure...
, and
inventorAn inventor is a person who creates or discovers a new method, form, device or other useful means. The word inventor comes form the latin verb invenire, invent-, to find...
. Born in a mixed family between a
PolishPoland , officially the Republic of Poland , is a country in Central Europe . Poland is bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
nobleSzlachta is the noble class in the Kingdom of Poland, the Grand Duchy of Lithuania and the increasingly polonized territories under their control . The nobility arose in the late Middle Ages and existed through the 18th century and into the 20th century...
family originating from Mazowsze, and a
RussianThe Russian people are an ethnic group of the East Slavic peoples, primarily living in Russia and neighboring countries....
noble family. Emigrated to
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
due to political
persecutionPersecution is the systematic mistreatment of an individual or group by another group. The most common forms are sexual persecution i.e.; persecution of women, religious persecution, ethnic persecution, and political persecution, though there is naturally some overlap between these...
after the assassination of
Alexander II of RussiaAlexander II Nikolaevich , also known as Alexander the Liberator was the Emperor, or Czar, of the Russian Empire from 3 March 1855 until his assassination in 1881...
(1881). He studied at the
Darmstadt University of TechnologyThe Darmstadt University of Technology, whose official name is "Technische Universität Darmstadt", in Darmstadt, Germany plays a significant role among German universities...
(TH Darmstadt) in
GermanyGermany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium,...
. From 1887 he worked for
AEGAllgemeine Elektrizitäts-Gesellschaft is a German producer of electrical equipment founded in 1883 by Emil Rathenau....
.
One of the founders (the second one was Tesla) of
three-phaseIn electrical engineering, three-phase electric power systems have at least three conductors carrying voltage waveforms that are 2π/3 radians offset in time...
systems. He developed the
three-phasePolyphase may refer to:* Polyphase matrix, in signal processing* Polyphase system, in electrical engineering* Polyphasic sleep...
electrical generatorIn electricity generation, an electrical generator is a device that converts mechanical energy to electrical energy. The reverse conversion of electrical energy into mechanical energy is done by a motor; motors and generators have many similarities...
and a
three-phaseIn electrical engineering, three-phase electric power systems have at least three conductors carrying voltage waveforms that are 2π/3 radians offset in time...
electrical motor (1888) and studied star and delta connections. The triumph of the three-phase system was displayed in Europe at the
International Electro-Technical ExhibitionThe 1891 International Electro-Technical Exhibition was held between 16 May and 19 October on the disused site of the three former “Westbahnhöfe” in Frankfurt am Main. The exhibition featured the first long distance transmission of high-power, three-phase electrical current, which was generated...
of 1891, where Dolivo-Dobrovolsky used this system to transmit electric power at the distance of 176 km with 75%
efficiency- In science and technology :* Efficiency , a count of desirability of an estimator* Algorithmic efficiency, optimizing the speed and memory requirements of a computer program* Efficiency factor, in data communications- In economics :...
. In 1891 he also created a
three-phaseIn electrical engineering, three-phase electric power systems have at least three conductors carrying voltage waveforms that are 2π/3 radians offset in time...
transformerA transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core, and thus a varying magnetic field...
and short-circuited (squirrel-cage)
induction motorAn induction motor is a type of alternating current motor where power is supplied to the rotating device by means of electromagnetic induction. It is also called asynchronous motor....
. He designed the world's first
three-phaseIn electrical engineering, three-phase electric power systems have at least three conductors carrying voltage waveforms that are 2π/3 radians offset in time...
hydroelectric power plant in 1891. During his life he obtained over 60
patentA patent is a set of exclusive rights granted by a state to an inventor or their assignee for a limited period of time in exchange for a public disclosure of an invention....
s.
In 1911 he received the
honorary doctorateAn honorary degree or a degree honoris causa is an academic degree for which a university has waived the usual requirements...
from the
TH DarmstadtThe Darmstadt University of Technology, whose official name is "Technische Universität Darmstadt", in Darmstadt, Germany plays a significant role among German universities...
.