Kálmán Kandó
Kalman Kando | |
---|---|
Born | 10 July 1869 Pest, Kingdom of Hungary |
Died | 13 January 1931 Budapest, Hungary | (aged 61)
Occupation | engineer |
Kálmán Kandó de Egerfarmos et Sztregova (egerfarmosi és sztregovai Kandó Kálmán; 10 July 1869 – 13 January 1931) was a Hungarian engineer, the inventor of phase converter and a pioneer in the development of AC electric railway traction.[1][2][3][4]
Education and Family
Kálmán Kandó was born on July 8, 1869, in Pest into an ancient Hungarian noble family.
Work on railway electrification
France
After his military service, he traveled to France in the autumn of 1893, and worked for the
Ganz Company, Budapest
In 1894, Kálmán Kandó developed high-voltage
In 1907, he moved with his family to
Italy, Designing the World's first electrified main railway line
In 1897, Kandó designed an electric system and engines for the Italian railways, the electric traction system had great advantages and importance on the very steep railway tracks in the mountainous regions of Italy. Under his leadership, the Ganz factory began work on three-phase haulage for railways. Based on their design, the Italian Ferrovia della Valtellina was electrified in 1902 and became Europe's first electrified main line railway.
For the Valtellina line, three-phase power was supplied at 3,000 volts (later increased to 3,600 volts) through two overhead lines, while the running rails supplied the third phase. At junctions, the two overhead lines had to cross and this prevented the use of very high voltages.
The three-phase, two wire, system was used on several railways in Northern Italy and became known as "the Italian system". There are now few railways which use this system.
In 1907, the Italian government decided for the electrification of another 2000-km railway line with the restriction that the electrical equipment and rolling stock could only be manufactured in Italy. The Westinghouse Company bought up Kandó's patents and paid a license-fee for the electric motors of the Ganz factory. The Westinghouse Company also built a locomotive factory in Vado Ligure, and appointed Kandó to head the new factory. Kandó accepted the invitation and moved to Vado in Italy with his several Hungarian colleagues. Two types of locomotives were developed with his leadership in Italy: a 1500 kw cinquanta[clarification needed] and a 2100 kw trenta[clarification needed] electric locomotives, from which altogether some 700 units were produced. 540 of these were still in service in 1945, the last three-phase line worked until 1976. In honour of Kandó’s work, he was awarded with Commendatore dell'Ordine della Corona d'Italia (Commander of the Order of the Crown of Italy), but in 1915 he had to flee through Switzerland, since Italy entered World War I on the Entente side and declared war on the Austro-Hungarian Monarchy.
Electrification of the London underground lines, a moral victory
On the District and Metropolitan Railways, the use of steam locomotives led to smoke-filled stations and carriages that were unpopular with passengers and by the early twentieth century electrification was seen as the way forward.[14] A tender was announced for an electric system, and the largest European and American companies applied to win the tender. However, when the experts of the railways compared the designs from the Ganz Works to the offers of the other large European and American competitors, they concluded that Ganz Works' technology was cheaper and more reliable and described its technology as a "revolution in electric railway traction".[15] In 1901, a metropolitan and district joint committee recommended the
Vienna, invention of the phase converter
During World War I, between 1916 and 1917, Kandó was a lieutenant completing military service for the Ministry of Defence in Vienna. He worked out a revolutionary system of phase-changing electrical hauling, whereby locomotives were powered by the standard, 50-period, single-phase alternating current used in the national energy supply system. He was the first who recognised that an electric train system can only be successful if it can use the electricity from public networks. In 1918,[19] Kandó invented and developed the rotary phase converter, enabling electric locomotives to use three-phase motors whilst supplied via a single overhead wire, carrying the simple industrial frequency (50 Hz) single phase AC of the high voltage national networks.[20]
Hungary
To avoid the problems associated with the use of two overhead wires, Kandó developed a modified system for use in Hungary. Power semiconductors not having been invented yet in the 1930s, the Kandó V40 locomotives' systems relied on electromechanics and electrochemistry.
Kandó synchronous phase converter
Single-phase power was supplied at 16,000 volts and 50 Hz through a single overhead line and converted to three-phase on the locomotive by a rotary phase converter.[21] The drive motors, made by Metropolitan-Vickers, had a very large diameter of 3 meters and incorporated four sets of 24 magnetic poles each, which could be added to the traction effort at will, producing highly efficient constant speeds of 25, 50, 75 and 100 km/h over rail (or 17/34/51/68 km/h for the V60 heavy freight train engine variant, which had six pairs of smaller driving wheels).
He created an electric machine called a synchronous phase converter, which was a single-phase
It had two independent windings:
- The outer winding is a single-phase synchronous motor. The motor takes the power from the overhead line.
- The inner winding is a three-phase (or variable-phase) synchronous generator, which provides the power for the three- (or more) phase traction motors.
The
- V40 Engine details
The greatest challenge was the creation of a locomotive capable of operating on a 50-cycle power supply. The first prototype locomotive was built in 1913 and underwent modifications based on operational experience. Test runs were conducted on the Budapest-Alag trial line. These experiments led to the development of the V40 series phase-shifting locomotive, also known as the Kandó locomotive. It had a power output of 2500 horsepower. The 16 kV, single-phase current taken from the overhead line was directly supplied to the primary winding of the phase shifter through the pantograph and the main switch. The phase shifter was an innovative solution that was ahead of its time. This was an extremely complex electrical machine. Its primary winding was located in the stator. This winding, along with the rotor excited by direct current, functioned as a single-phase synchronous motor. The rotor, located in the slots of the stator cores, induced 3, 4, or 6-phase voltages according to the switching sequence. Therefore, the secondary winding forms a multi-phase generator with the rotor. Thus, the phase shifter combines a single-phase synchronous motor and a multi-phase generator in one machine. Noteworthy is the water cooling system integrated into the windings of the rotor. The locomotive's only motor, a multi-phase induction motor, received a voltage of around 1000 V from the phase shifter. The phase shifter provided a constant 50-cycle current, so changing the speed and rotation was achieved by switching the motor's pole number. The continuous transition between synchronous speeds resulting from pole switching was ensured by water resistance.
- Power factor
A major benefit of this arrangement was a power factor of nearly 1.00 in the catenary-attached equipment, which fulfilled the electric powerplants' strict load-distributing regulations. The unacceptably poor power factor of pre-World War II design electric motors (occasionally as low as 0.65) was not felt outside the Kando locomotives, as the phase changer machinery provided isolation.
- Speed control
Intermediate speeds were maintained by connecting a water and saltpeter based adjustable resistor to the line, which reduced the efficiency of the locomotive. Timetables for electrified lines were supposed to allow use of full efficiency constant speeds most of the time but, in practice, the need to share the track with trains hauled by MÁV Class 424 steam locomotives meant the water-hungry and wasteful "gearbox resistor" had to be used often.
- Kandó triangle drive
The propulsive force was transferred to the locomotive's wheels using a traditional pushrod system, designed to provide manufacturing and maintenance commodity to the predominantly steam-based Hungarian Railways (MÁV) of the time. The so-called
- Shaft drive
More than a decade after Kandó's death two new, shaft-driven prototypes of his design were built by the Ganz company, to allow for 125 km/h traction speeds. The V44 electric locomotives
- Bogie-mounted motors
After the second World War, a last series of electric phase-changer locomotives were built by the new
- Preservation
Currently one example of the V40,[26] the V55[27] and the V60 locomotive[28] each survives. They are preserved at the Budapest Railway History Park, but require restoration after decades of open air static display. If funding permits, the repaired V40 may return to the open track for "nostalgic service", with a semiconductor front-end added to its system for 25 to 16 kV AC down-step conversion.
France
Kandó designed in 1926 the 1.5 kV DC 2BB2 400 (fr:2BB2 400) for the Paris-Orleans line which were the strongest DC locomotives in Europe at that time. The Ganz Works of Budapest, Hungary supplied these two locomotives, to the design of Kálmán Kandó.[29]
United Kingdom
8 years after the death of Kandó, the engineering office of the Ganz Works won several British tenders, which were mostly based on Kandó's latest technology. British firms were entrusted with the implementation of these plans. There were plans to use the two-wire, three-phase, system on the Portmadoc, Beddgelert and South Snowdon Railway in Wales and the Metropolitan Railway in London but neither of these plans came to fruition due to the outbreak of WW II.
Death and legacy
Kálmán Kandó died of unexpected heart failure in Budapest on January 13, 1931. The ever-increasing strain of work, a series of family tragedies, the hassle of his life's work, and the foreign bank loan that influenced the implementation of the phase-change system, all combined to strain Kandó's sudden death.
He did not live to see the final commissioning of his system, the realisation of his masterpiece, the locomotive he had designed. On 17 August 1932, the first phase-changing locomotive, V40 001, was tested by the engineers. After his death, the development of the electric locomotive continued on the path he had set, under the direction of Ferenc Ratkovszky and Andor Mándi.
Many modern electric trains work on the same three-phase high tension AC principle introduced by the Kandó V40 locomotives, but the rotary converter is replaced by
The number of Kálmán Kandó's patents granted between 1895 and 1929 is 69. More than 50 patents were bought by locomotive and rolling stock manufacturing companies in foreign countries like the UK, US, Germany, France and Italy. The patents are grouped around the topics of electric railway motors, multi-phase AC motors, automatic railway switching devices, overhead lines, phase converters, railway safety techniques and power transmission stations.
In
See also
- List of railway electrification systems
- Railway electrification
- Three-phase AC railway electrification
References
- ^ "KÁLMÁN KANDÓ". Hungarian Intellectual Property Office. 2015-02-05. Retrieved 2024-02-06.
- ^ Foundation, Tempus Public. "Study In Hungary - Famous Hungarian inventions". studyinhungary.hu. Retrieved 2024-02-06.
- ^ "The brilliant Kálmán Kandó – One of Hungary's greatest design engineers". pestbuda.hu. 2021-01-16. Retrieved 2024-02-06.
- ^ "Hungary – Association of Hungarian Inventors - MAFE" (PDF). inventor.hu. p. 2.
- ^ "familysearch.org Kandó Géza gyászjelentése".
- ^ "familysearch.org Kandó Kálmánné Posch Ilona gyászjelentése".
- ^ Antal Ildikó (2014): A magyar villamosenergia-ipar 1896–1914
- ISBN 9780966573428.
Evian-les-Bains kando.
- ISBN 9780912404042.
- ^ C.W. Kreidel (1904). Organ für die fortschritte des eisenbahnwesens in technischer beziehung. p. 315.
- ^ Elektrotechnische Zeitschrift: Beihefte, Volumes 11-23. VDE Verlag. 1904. p. 163.
- ^ L'Eclairage électrique, Volume 48. 1906. p. 554.
- ^ "Kálmán Kandó | Óbudai Egyetem". uni-obuda.hu. October 8, 2015.
- ^ Horne 2003, p. 28.
- The Register (Adelaide). Vol. LXVI, no. 17, 061. South Australia. 1901-07-19. p. 6. Retrieved 2021-06-21 – via National Library of Australia.
- ^ Green 1987, p. 24.
- ^ Horne 2006, p. 37.
- ^ Green 1987, p. 25.
- ISBN 9780852968055.
- ^ Hungarian Patent Office. "Kálmán Kandó (1869–1931)". www.mszh.hu. Archived from the original on 2010-10-08. Retrieved 2008-08-10.
- ^ "Image: SPLIT33.JPG, (459 × 534 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ^ Frigyes Andor-Szita Iván-Tuschák Róbert-Schnell László: Elektrotechnika (Tankönyvkiadó, Budapest 1951) 758. oldal
- ^ "Image: ka_drv.jpg, (734 × 377 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ^ "Image: V44_1.JPG, (764 × 456 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ^ "Image: V55_1.JPG, (726 × 432 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ^ "Image: ka1.jpg, (645 × 363 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ^ "Image: V55.jpg, (1275 × 856 px)". upload.wikimedia.org. 2004-08-06. Retrieved 2015-10-09.
- ^ "Image: V60.jpg, (686 × 322 px)". erojr.home.cern.ch. Archived from the original on 2011-07-06. Retrieved 2015-10-09.
- ISBN 0-86288-351-2.
Works cited
- Green, Oliver (1987). The London Underground: An illustrated history. Ian Allan Publishing. ISBN 0-7110-1720-4.
- Horne, Mike (2003). The Metropolitan Line. Capital Transport. ISBN 1-85414-275-5.
- Horne, Mike (2006). The District Line. Capital Transport. ISBN 1-85414-292-5.