History of 3-phase Electricity & Distribution

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  • čas přidán 25. 12. 2021
  • Who invented 3-phase electrical distribution? Nikola Tesla? Mikhail Dolivo-Dobrovolsky? In this video I go through the detailed history from primary sources of this important EE discovery, how it works, and why it is important.
    Links:
    My mailing list (with a link for a video on the history of 2 phase)
    kathylovesphysics.ck.page/wel...
    My Patreon Page:
    www.patreon.com/user?u=15291200
    As usual, a big thank you to the fabulous Kim Nalley for singing "electricity" and some background music. www.kimnalley.com
    Citations:
    Alfred, R “Aug 14, 1888: I Sing the Meter Electric” Wired Magazine (Aug 14, 2008)
    Thompson, S Polyphase Electric Currents and Alternate-current Motors (1900) p. 444
    “Mr. Nikola Tesla on Alternating Current Motors” The Telegraphic Journal and Electrical Review vol. xxiv (June 7, 1889) p. 648
    Carlson, W Tesla: Inventor of the Electrical Age (2013) p.113
    Tesla, N “Tesla’s Tribute to Westinghouse,” The Age of Steel LXXXVIII, no. 10 (September 1900), 9.
    William Stanley “The Induction Motor” Engineering News (Oct 2, 1902) vol. XLVIII No. 14 p. 279
    Frank Sprague to Sprague Executive Board (leaked to Edison) (April 29, 1890) Edison Papers Digital Edition [X120CBN]
    Jonnes, J Empires of Light (2003) p. 223
    Leupp, F George Westinghouse: His Life and Achievements (1919) p. 159
    Skrabec, Q George Westinghouse: Gentle Genius (2007) p. 130
    “Mikhail Dolivo-Dobrowolsky (1862-1919)” [in Russian] Vavilov, S People of Russian Science: Essays on Outstanding Figures of Natural Science [Люди русской науки: Очерки о выдающихся деятелях есте- ствознания и техники] (1948)
    Dolivo-Dobrowosky, M "Transmission of power by rotary-phase alternate currents", Electrical Engineer (London), vol. 7, p 369, (April 10, 1891)
    “The invention of the electric motor 1856-1893” Elektrotechnisches Institut (ETI) www.eti.kit.edu/english/1390.php
    Thompson, S Polyphase Electric Currents (1900) p. 173
    Thompson, S Elementary Lessons in Electricity and Magnetism, (1894) p. 507
    Ushakov, V “Electrical Power Engineering” (2017) p. 16
    Allerhand, A “The Earliest Years of Three-Phase Power” Proceedings of the IEEE vol. 108 (Jan, 2020) p. 215-6
    Herausgegben vom Vorstand der Ausstellung Offizieller Bericht über die Internationale elektrotechnische Ausstellung in Frankfurt am Main, 1891 (1894) p. 324
    Lightning: Volume 1 (April 28, 1892) p. 509
    “The Transmission of Power at Frankfort” The Electrical Engineer (Sept 18, 1891) p. 286
    Brown, C “Reasons for the Use of the Three-Phase Current in the Lauffen-Frankfort Transmission” The Electrical World (Nov 7, 1891) vol. XVIII No. 19 p. 345
    Nikola Tesla patent US 382,280 “Electrical Transmission of Power” (May 1, 1888)
    “Mr. Tesla’s Experiments” (April 6, 1892) Electrical Engineer vol 13-14, p. 350
    Lamme, B “The Story of the Induction Motor” (March 1921) Electrical Engineering (New York) vol. XL p. 205
    Tesla’s patent was co-owned by supporters Alfred Brown and Charles Peck, according to Carlson, B Tesla: Inventor of the Electric Age p. 130 “Since they had shrewdly handled the business negotiations and assumed all of the financial risk in developing the motors, Tesla gave Peck and Brown five-ninths of the proceeds from the deal while retaining four-ninths for himself”
    Lamme, B Benjamin Garver Lamme, Electrical Engineer, An Autobiography (1926) p. 61
    Lamme, B “The Story of the Induction Motor” (March 1921) Electrical Engineering (New York) vol. XL p. 212
    Davis, L Fleet Fire: Thomas Edison and the Pioneers of the Electrical Revolution (2012)
    “Westinghouse paid Tesla $216,600” “Annual Report of the Board of Directors of the Westinghouse Electric” Electricity (June 30, 1897) p. 387
    Gordenker, A “Japan’s incompatible power grids” Japan Times vol. 19 (July, 2011) p. 9
    Dolivo-Dobrowolsky “Transmission of Power by Rotary-Phase Alternative Currents” The Electrical Engineer (April 3, 1891) p. 336

Komentáře • 2,3K

  • @deaniegarcia5694
    @deaniegarcia5694 Před 10 měsíci +64

    I am a retired EE, and never paid much attention to power systems, preferring information and computation,but you make this stuff compelling! I watch your videos often, and it, almost makes me want to go back to work! Keep up the great work!

  • @andyo1872
    @andyo1872 Před 2 lety +94

    I didn't know about Dolivo-Dobrovolsky's greatest inventions until today( I never heard about him either). Thanks to you Kathy now I know who really invented the most practical and efficient 3-phase AC. Dolivo-Dobrovolsky is so under rated ! 3-Wire 3-Phase !! What a genius !

    • @LucIan-er2ir
      @LucIan-er2ir Před rokem +3

      it depends of which sponsorig have 🙂

    • @raymondgarafano8604
      @raymondgarafano8604 Před rokem +1

      YUP, but is it a Y or Delta (meaning a triangle) which came first? Is the Y better for
      lighting or motors? A Delta can have a center tap in the midst of a winding to give
      120 volts while a Y will give 1.732 X the voltage from phase to phase as compared to
      the voltage from the neutral or one side of the three windings to a phase conductor.

    • @BPo75
      @BPo75 Před 8 měsíci +2

      @@raymondgarafano8604 With the D-configuration you will have the main voltage across the windings at all times (centre tap to 120V is an abomination that offers no real advantage except an insignificant reduction of insulation needed), but you won't have a neutral point.

  • @KeritechElectronics
    @KeritechElectronics Před rokem +8

    As a Polish electrician and electronics hacker, I'm proud of Dolivo-Dobrovolsky and absolutely delighted with this episode :)
    Oh, and there are a few other important Polish inventions in electrical engineering: a FW bridge rectifier (or, as Electroboom would call it, FULL BRIDGE RECTIFIER!) and an electrolytic capacitor - both invented by Karol Pollak. How would electronics look now if not for him? I guess we'd still go with the centertapped windings.
    To think that most of the principles and inventions lied out by him are the mainstay of modern electrical distribution systems, though now that we've got highly efficient DC/AC converters, we may be seeing some DC power system resurgence especially in the international ultra high voltage networks, not to mention the solar installations. DC switching on the other hand, arc quenching in particular... makes me wonder if it can be easily solved using IGBTs or FETs (thyristors won't do, they stay latched until power is cut off, making them useless for this purpose).

  • @krivokucavladimir
    @krivokucavladimir Před rokem +3

    Long live Dolivo Dobrowolski, Forget Nikola Tesla. This great discovery. Even greater than all the discoveries of Nikola Tesla. Well done, dear lady, for opening our eyes.

  • @seeratlasdtyria4584
    @seeratlasdtyria4584 Před 2 lety +428

    Simply put, this is a better explanation of these events, than I heard in my EE Engineering classes at UCLA, LOL. Kathy, I do not know your history, but you were, imho, born to teach:) Thumbs up across the board.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +32

      Thanks so much

    • @Dennisaj
      @Dennisaj Před 2 lety +47

      If a CZcams content creator Does a better job at explaining electrical engineering, Then a professor at UCLA… Than why the heck is college so expensive???

    • @seeratlasdtyria4584
      @seeratlasdtyria4584 Před 2 lety +24

      @@Dennisaj excellent question, the answer is something called 'tenure' :)

    • @HyperactiveNeuron
      @HyperactiveNeuron Před 2 lety +19

      I 100% agree. This is like 4 or 5 different lectures and probably more than 2 or 3 classEs. Power systems and electromechanics was my favorite subject and I never heard all of this together or this organized.

    • @ohboy4784
      @ohboy4784 Před 2 lety +15

      Well,
      There is a huge difference between teaching "History of science " and actually doing or teaching science ...huge difference.

  • @rogerw9840
    @rogerw9840 Před rokem +34

    Fun fact:
    The 18th of December 1893 the worlds first commercial 3-phase power transfer was inaugurated. The transfer line ran between Hällsjön (the source, water turbine IIRC) and Grängesberg (at the time one of the largest iron ore mines in Europe) in southern Dalarna, Sweden. The distance of the transfer was 13 kilometers and transferred up to 9300 Volt. Remains of the facilities can be seen to this day.
    A testing and demonstration facility connecting Lauffen and Frankfurt in Germany had been in operation for a few years before.

    • @BPo75
      @BPo75 Před 8 měsíci +1

      Jonas Wenström is sadly unknown outside Sweden.

  • @ai4px
    @ai4px Před 2 lety +7

    You should do a video about the frequency of the line. Motor users wanted lower frequencies, and lighting wanted higher frequencies. Various grids were from 16hz to 100hz over the years and finally settled on 60hz after WW2. Also there' a national time keeper to keep track of the number of 60hz transitions per day and run the grid a little faster or slower at night to "catch up" so our bedside clocks stay accurate. Lots of stuff about this that would be right up your alley!!

  • @jimkillen1065
    @jimkillen1065 Před 8 měsíci +4

    I worked at a power plant for 35 years and studied the basics classes back then. At the first power plant i worked at it was very old unit . The equipment worked well but has long since been removed. Glad i ran onto this channel. I certainly watch more of your videos . I remember i think that air craft were a lot higher frequency . Thanks for the history lesson..

  • @krishnaprasadlama9432
    @krishnaprasadlama9432 Před 2 lety +127

    Dobrovolsky's contribution in the development of 3-wire 3-phase electricity was really an eye opener for me as I had all along thought that Tesla was the sole inventor.I had known of the contribution of Steinmetz however.

    • @europoamerico7605
      @europoamerico7605 Před 2 lety +3

      This is all bull. Specially coming from a woman. Tesla invented ac period

    • @angrydoggy9170
      @angrydoggy9170 Před 2 lety +19

      @@europoamerico7605 Nope he didn’t. It was invented years before he was born.

    • @bwfvc7770
      @bwfvc7770 Před 2 lety +2

      @@europoamerico7605 from memory the first ac was generated by a French woman using a Faraday designed machine. The commutator was introduced to this machine by Andre-Marie Ampere, thus producing the first generated, rudimentary dc.

    • @scamper_van8470
      @scamper_van8470 Před 2 lety +7

      It doesn't change much whom invented what.
      Tech should be available to everybody,but now days Tech has become only profits and no benefits for everyone, but the end results its the same.
      Tech make rich some and screw over the rest,a truly excellent tech is the one that once built last over time and not break after 1 2 years due to the fact that Markets need something new every few months to make more profits...
      In the facts is the human kind greed that is driving today's world,along with non stop pollution of the planet.
      On which we all live and when the planet dies we all will die with the planet..
      Capitalism and Political Corruption...
      🤣🤣🤣🤣🤣🤣🤣🤣🤣

    • @jourwalis-8875
      @jourwalis-8875 Před 2 lety +1

      @@europoamerico7605 This is sex discrimination!

  • @marcosfingerhut3011
    @marcosfingerhut3011 Před 2 lety +223

    Kathy, the difference you're pointing that Tesla's three phase motor needed 6 connecting wires and Dolivo´s had only 3 makes a world of difference and thanks to you I can see where these two
    inventors differ and the huge Dolivo-Dobrovolsky´s breakthrough. How elegant is Dolivo´s 3 wires solution; I'm in awe !. Thank you for helping me see it so clearly !

    • @mikelang4853
      @mikelang4853 Před 2 lety +13

      Invention is needed in order for refinement to occur.

    • @Bialy_1
      @Bialy_1 Před 2 lety +14

      "Doliwa - is a Polish coat of arms. It was used by several szlachta families in the times of the Polish-Lithuanian Commonwealth."
      Dobrowolski is the family name and you can translate it as "Goodwill".
      But i agree that is very well made video and amazing work made by Kathy.

    • @gordongecko9405
      @gordongecko9405 Před 2 lety +1

      @@Bialy_1 O tym że system 3-fazowy to wynalazek Polaka to wiedziałem, i tą wiedzę propagowałem. Ale co to jest 'doliwa' to już nie. Dzięki.

    • @costiqueR
      @costiqueR Před 2 lety +10

      In fact, this is a key observation, I just saw the full episode and I was angry on so many years of misinformation. Tesla added his 3 coils variant as a variant of the 2 phases device, no study really in the background. As a filling of possibilities in the patent. He did not know the huge difference between 2 and 3 phases. In fact, all that we use today is the AEG system, so is clear for me in one moment the Americans understood but was no way for them to recognize it... Tesla himself probably knew it best.

    • @marcosfingerhut3011
      @marcosfingerhut3011 Před 2 lety +10

      @@costiqueR Exactly. Tesla did not know the HUGE difference between 2 phases and the REAL (Dovrowolsky´s) three phase with only three wires.

  • @georgewhitehead8185
    @georgewhitehead8185 Před 2 lety +1

    As always, a fantastic video. Just a comment at 23:30-31she incorrectly reads the word "Indubitably" as undoubtably, and pronounces it that way. But the word is "indubitably" and should be pronounced as "in-doo-bi-tuh-blee." Now don't any of you send me "hate mail" as I love her work, her genius, and her clear headed presentations. But equally, as I love her presentations, I also love words, and must point out that the word is Indubitably and is pronounced as "in-doo-bi-tuh-blee." Thanks to you Dr. Kathy, and thanks to all of your fans who are reading this. Dr. George Whitehead

  • @AnbroBR
    @AnbroBR Před 9 měsíci +8

    As an industrial electrician for over 40 years, I routinely worked with 240 volt and 480 volt 3-phase systems. The 3-phase systems were not all the same. Some were configured as "wye" and the others were configured as "delta." To top that off, in one factory in which I worked, they used a 240 volt 3-phase system with one of the "phases" (conductors) grounded. This was called a "grounded B-phase system." Most factories do not use this system.
    Excellent videos, Kathy!

    • @RecordProduction
      @RecordProduction Před 9 měsíci

      480v ?

    • @TantalumPolytope
      @TantalumPolytope Před 8 měsíci

      @@RecordProduction American 3 phase system

    • @AnbroBR
      @AnbroBR Před 8 měsíci

      No, the grounded B-phase system was 240 volts. The factory also had 480 volt, 3-phase systems that had the normal ungrounded conductors. Thank you.@@RecordProduction

    • @AnbroBR
      @AnbroBR Před 8 měsíci

      Yes, 480 volts. Some of their 480-volt, 3-phase systems were 480 volt / 277 volt, wye connected systems.@@RecordProduction

  • @chrisnurczyk8239
    @chrisnurczyk8239 Před 2 lety +94

    Not only do I now understand the history of this form of energy distribution, I finally have a better working understanding of the manner in which AC works in modern systems. Great job, Kathy. As a retired middle-school Natural Sciences teacher and junior college Horticultural Adjunct, it's wonderful to see someone explaining science in such a meaningful manner, using original sources. Pray, continue!

  • @alfabsc
    @alfabsc Před 2 lety +212

    I thought I knew this history. The Westinghouse+Tesla vs Edison story is very familiar to me. I had never heard of Dolivo-Dobrovolsky. Thanks for clearing up the details of how 3-phase became dominant electrical distribution system.

    • @kevinmithnick9993
      @kevinmithnick9993 Před 2 lety +12

      X2. I thought Tesla was the only one and the creator of virtually everything

    • @ktaragorn
      @ktaragorn Před 2 lety +12

      Same! Feels like his innovation was more impactful than either of edisons or teslas.. and impressive that it has stood the test of time as well!

    • @clivebaxter6354
      @clivebaxter6354 Před 2 lety +1

      There was no Tesla V Edison

    • @wiadroman
      @wiadroman Před 2 lety +7

      @@kevinmithnick9993 Well, you were wrong. Tesla invented only 50% of everything, the other 50% was invented by Da Vinci.

    • @kevinmithnick9993
      @kevinmithnick9993 Před 2 lety +12

      @@wiadroman Well, 50% of everything is still a lot. Is sad nowadays we are more worried who is taking more attention than who is doing more. Yes, there is a difference. Good to see at least 0.000001% of world population devotes their lives to human adavancing as civilization. Unfortunatelly that number is in decline

  • @andys9678
    @andys9678 Před rokem +8

    Thanks!!! If young students were tought all these stories we would have more engineers... and we need them

  • @robs2203
    @robs2203 Před 2 lety +42

    Thanks to your presentations Kathy, as a retired electrical engineer, I am still exited about the beginnings of the sciences and their industrial implementation.

  • @parameciumbrains
    @parameciumbrains Před 2 lety +5

    A little bit of Clarification at 15:29
    The picture of Tessa's 3 phase six wire transmission, is a standard motor found in the market today. The wires ends are labeled U1, V1, W1; U2, V2, W2. Because of this you can make this motor a Delta or Star or other motor, At the time of installation depending how you jump the connections. Some systems change these jumpers while running but it's rare nowadays. When you see one it's a real delight, especially when you see a person see it for the first time.
    The picture of M. Von Dolivo is not showing that he made 3phase but that he was working on an Improvement on his Transformer, on the right half of that picture. On the left half of his picture is a 3-phase Delta Dyno that uses slip rings. Motor with slip rings are not used very often anymore but were in the early days to help adjust the resistance of a motor dynamically. This was to help produce better running torque. In the illustration he is not dynamically changing the resistance of the slip rings. But this is something he is given credit for. Vons motor is set up as a delta.

  • @ephemeralvapor8064
    @ephemeralvapor8064 Před 2 lety +101

    This is the best video per minute of time I've seen on the history of this subject by far - good job and thank you.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +7

      Thank you for the lovely comment. Made my day. 😊

    • @chuckthebull
      @chuckthebull Před 2 lety +3

      @@Kathy_Loves_PhysicsIll have to agree with mr or mrs Vapors,,, I have been an electronics engineer repair guy tinkerer and instrument maker and now in my 60s still doing work in film and i have to say your videos are really enjoyably to watch and this old dog has even leaned a few new tricks ( or at least history) of a few things even i did not know.. Thanks for taking the time and effort to do these vids and research all this wonderful history. I love your style and enthusiasm telling these stories. keep it up!

    • @Matlockization
      @Matlockization Před 2 lety +2

      @@Kathy_Loves_Physics Nicola Tesla is not serbian. When asked by a reporter where he was from, he said Austro-Hungarian which the area is current day Croatia.

    • @dennishillman3502
      @dennishillman3502 Před 2 lety +5

      I have worked on and designed 3 phase systems for 30 years. I cant count how many books and papers I have read on the subject and this video had me rethinking a lot of what I have learned. Thanks for all the hard work researching this.

    • @mobilemcsmarty1466
      @mobilemcsmarty1466 Před 2 lety +1

      I will second that opinion. thanks Kathy! I just found your channel and will go to watch the rest of your vids. may I humbly suggest to wear a microphone I can better hear your lovely voice and content 🙂

  • @keithdaniel6028
    @keithdaniel6028 Před 2 lety +23

    I'm surprised I wasn't taught this in grade school, but I learn it 50 years later from this wonderful lady who loves physics & history.

    • @Trucmuch
      @Trucmuch Před 2 lety +2

      I'm not. As interesting as it is, it's not really something you learn in school. I do not know what you studied. But if you studied history, that's a bit too electricity-specific to be learned. If you study physics, it's more a historical thing than an electric thing.
      Now, if you study the history of electricity, I'm with you, you should have learned that!

  • @gregr1672
    @gregr1672 Před 6 měsíci +2

    I was lucky enough to make deliveries at the huge Westinghouse Electric Plantnin East Put ,Pa . In 1982 they still were the go to for the worlds largest best generators,transformers . I delivered to all the Depts ,the most impressive was the High Energy Lab. They would do blasts of currents that would make the hair stand up on your neck. Red lights and alarms would sound when testing . They had some of the biggest lathes and machinery in the world.With deep pierings needed to support them .I also like the LRA large rotating apparatus plant .Those guys wound the transformer so large they stood inside them on platforms .Place should have become museum of Industry .

  • @ryanroberts1104
    @ryanroberts1104 Před 2 lety +7

    Very well done. People usually think I'm a weirdo when I start talking about 3 phase power...I think "most" people literally don't even know it's a thing. I used to have a big old warehouse building that was fully electric in 1910, it had modern power service but all of the original 1910 3 phase knob and tube stuff was in place and disconnected. Incredible to look at and see how advanced it was for the time. The distribution board with the slate back and live knife switches looked like something from a movie set. At over 100 years old, add some plastic insulation and change fuses for breakers and it's an almost identical system to what we are still using today.
    The original light switches were all rotary - this is why we say *turn* on the lights when we mean flip a switch. They have a neat little window with the word on or off when you turn it.

  • @RANDALLOLOGY
    @RANDALLOLOGY Před 2 lety +6

    In all my 50 years being in electronics with a bachelor's degree in electronic engineering, I never knew the information you just presented.
    I'm impressed ,and decided to subscribe.

  • @macalmy6750
    @macalmy6750 Před 2 lety +84

    I don't know why the CZcams algorithm sent you my way last week, but I'm glad it did. The level of detail and citation you go into is wonderful, and you're a great story teller. Too much of what gets taught in science classes about the history of science seems to be more like folklore, so it's wonderful to find someone who digs in to get the details right.

  • @yosuto5810
    @yosuto5810 Před rokem +3

    Great video! I'm electrical engineering student and there is a lot of talk about Michał Doliwo-Dobrowolski at my university. There is even a statue of him near the building. I wonder how many underrated scientists there are, who didn't have the political circumstances to become globally known.

  • @sammyk7024
    @sammyk7024 Před 2 lety +3

    This has to be one of the best science channels on YT, and probably the most underrated.
    Informative, accurate, educational, and brilliantly entertaining. Kathy, you are such a wonderful story teller! It is nothing but a privilege to have free access to the contents you make. Thank you so much!

  • @goranljungek2790
    @goranljungek2790 Před 2 lety +6

    The first transmission of threephase was made in Sweden with Wenstrom system. That was the beginning of ASEA, today know as ABB.

  • @steveremington
    @steveremington Před 2 lety +9

    Hi Kathy, As a former electrician who worked in the electricity distribution sector and a person who has an interest in the history of science and engineering, your channel is my new CZcams happy place.
    Thanks for the putting in the effort to create interesting and informative videos. No it's back to binge watching the rest of your videos.
    I look forward to buying and reading your books when they are published.

  • @alanparkinson549
    @alanparkinson549 Před 2 lety +4

    Fascinating stuff, especially as I worked as a design and test engineer for a transformer manufacturing company way back in the 1970s.
    I couldn't do history to save my life at school, but I love the history of science and technology.

  • @xtalvt
    @xtalvt Před 2 lety +16

    Awesome job !!!!!! I build electrical control panels for several clients including Westinghouse Nuclear (worked as an engineer for them a decade ago). Your timeline is sooooo much clearer than any I had read. I also did not know where the 50 vs 60 Hz came from ... loved that part of the story! Thanks so very much !!!!!!

  • @mrgcav
    @mrgcav Před 2 lety +67

    I just discovered you channel. It is great.
    As an American, I thought I was taught the whole story of electricity. But came to realize I only knew the American version and much was deleted or skipped entirely. American versions of history tend to exclude all others. People like Dolivo Dobrovolshy are completely overlooked. Maxwell is said to have moved to America in some books I read. Untrue Thank you for filling in all the true details.

    • @millomweb
      @millomweb Před 2 lety +1

      The English do that too. Americans only copied the idea from the English ;)

    • @Mr.Swann.
      @Mr.Swann. Před 2 lety +3

      @@millomweb No, you're wrong. We give credit where, (and to whom), it's due - Xenophobic tunnel vision, (and selective recall), tends to be a largely American, (and to a lesser extent, Russian), phenomenon, (although I concede that Russian originality of thought and technical prowess puts that of Americans to shame .. you really didn't do very well with rocketry, for instance, before Von Braun launched 'Explorer' for you, (all credit to you Yanks for that, of course; good 'American' name .. 'Von Braun' ..), on top of a Redstone rocket, (essentially, his A4/V2 on steroids, just AFTER the launch of Sputnik 1). The English, (and in case you hadn't guessed, I am a 'Brit'), are usually a bit strapped for cash & are thus driven to create, (we don't usually copy), extremely elegant, simple, (cheap), and original solutions to technical problems, (for instance, using a silver mesh to safely catalyse conc.H2O2 in monopropellant rocket engines thus removing the need for a liquid catalyst & doubling the amount of H2O2 carried for the same weight.) Secondly, if, hypothetically speaking, we 'Brits' HAD been guilty of such execrable behaviour, surely the Americans would not be so weak-minded as to merely 'ape' that behaviour ? .. As your parents might have taught you .. "Would you also put your hand in the fire if someone else did it first?" .. Oh well ..

    • @millomweb
      @millomweb Před 2 lety +2

      @@Mr.Swann. Having worked with someone who worked in France for a number of years, he was surprised to learn of all the nasty stuff the brits have done in the past that the brits don't generally get to hear about.

    • @Mr.Swann.
      @Mr.Swann. Před 2 lety +3

      @@millomweb Ah, yes, indeed. Our gallic 'sparring partners' over the centuries have an expression for that; in English, it is .. "PERFIDEOUS ALBION", (contemporary rendition would, perhaps, read .. "SNEAKY BRITISHNESS"). We've been hurling calumnies at one another for centuries to the point where it has become almost a National Sport. We have both competed for and had 'Empires' .. (to an extent, the French still do, and tend to treat those native to their remaining 'possessions' & 'protectorates' , it must be said, rather poorly.) The relevance of that statement is that most countries who secure independence from a 'Great Power', (not many of those remain, thankfully), run away, cheering, shouting, (bellowing whatever their National Equivalent is of the Confederate 'Rebel Yell' .. which I rather like, by the way), , & firing guns into the air ! .. HOWEVER , there is an 'agreement', 'confederacy', ''trading group of nations', (indeed, rather a mix of all of these), known as the BRITISH COMMONWEALTH. Countries which USED to be part of our 'Empire', but which are now independent, have tended to ASK to be PART of this, and remain so TO THIS DAY !! .. Canada, New Zealand, Kenya, Jamaica, India, (and quite a few others .. gosh, we DID get about a bit in the past, didn't we ?), are all members, and Australia, (who have had a couple of [referenda / referendae / referendums], am unsure of the plural form for 'referendum'), to see if they wish to forget their historical ties with us, but who's population stubbornly keep voting to stay IN this Commonwealth ! To conclude, for them to not actually detest those 'rotten chaps' who USED to 'exploit' their countries, one may, perhaps, wish to conclude that we weren't actually that bad ! .. We're still not ! There is a pragmatic reason for this; England is just one of a group of four countries forming the United Kingdom; three of these countries are on one, fairly small & crowded island. We must trade to survive, (and this has always been the case). To do this we HAVE to be fair and to 'get along' with, well, everyone ! .. (would you buy a car from someone who everyone told you was a crook, or from someone with a reputation for fairness & honesty ?) Hence, finally, you may perhaps, wish to ask your acquaintance who worked in France for verified DETAILS of .. (and I quote .. ), "all the nasty stuff the brits have done in the past that the brits don't generally get to hear about." We can then discuss this further. I enjoy a good debate, and have even been known to concede that I'm absolutely wrong, and to publically apologise .. IF it can be proven to me that I am ! .. (and most 'Brits' are fair, and open to reasoned debate in this way.) Regards, 'Swanny'; (feel free to call me that, if preferred; most of my friends do.)

    • @millomweb
      @millomweb Před 2 lety

      @@Mr.Swann. Plural referendums, referenda #OED
      I guess referendae would be the plural of referenda.
      Regarding devolution, why is it that no one discusses where borders should be ? What if Cumbria and Northumbria wanted to be Scottish ? If Cumbria wanted to be - then what about Lancashire ?
      What if the only place that didn't want to be Scottish was Westminster ?
      Och aye the noo !

  • @maxironpaw
    @maxironpaw Před 2 lety +41

    I am so glad that I happened upon your channel. Back in the 70s, my uncle, who had been a printer since the 1920s, called me for help. He had an ancient printing press that was needed for an important production run. There was something wrong with its motor and control system - its two-phase motor and control system! This was the first I had heard about two-phase as I only knew about single-phase and three-phase. This ancient machinery looked like you would expect early 1900s devices and controls to look like. Somehow I figured out what was wrong and got it all working. That was my first and only exposure to two-phase power. Thank you so much for this terrific history lesson. You have a new subscriber!

    • @rayoflight6220
      @rayoflight6220 Před 2 lety +3

      You can create the second phase - which has a 90 degree phase shift - with a capacitor.

    • @Farm_fab
      @Farm_fab Před rokem

      I was surprised a number of years ago that I noticed a 2 phase motor at the scrap yard. It was for sale, but I obviously had no use for it.
      Two phase can be made from single phase, but I'm not an engineer to discuss this. Lancaster Pennsylvania had been wired for 2 phase many years ago, and this motor was evidently from that era.

    • @davidberry8431
      @davidberry8431 Před rokem

      @@Farm_fab interesting
      . So there's a scrap yard where one can browse in Lancaster? I'm in nearby Palmyra, could tell me where this is? Thankee

    • @markhook499
      @markhook499 Před rokem

      7

  • @rgmoses2189
    @rgmoses2189 Před rokem +20

    I have never said this lightly but I love you! Your channel lit a fire in my heart over a year ago by showing me that electricity isn't as complicated as it looks on the outside while still having a close to limitless amount of uses that people would believe was just a load of fiction if they didn't see it with their own eyes. Because of you I am currently halfway through my freshman year in college majoring in electrical engineering followed by big plans based on the future uses and generation of electricity

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před rokem +6

      That makes me so happy. I’m sure you are going to do amazing things and I am honored to be a part of your story.
      Cheers,
      Kathy

  • @michaelschalck
    @michaelschalck Před 2 lety +12

    Great video :) Just a shame that Jonas Wenström was not mentioned, since he created a 3 phase transmission system on 9,5 kV in 1893 for the Swedish mining industry. And this was the initiator for placing the small town of Ludvika in Sweden on the map as a world leading center for power transmission.

  • @juliofoolio2982
    @juliofoolio2982 Před 2 lety +17

    Thank you Kathy. I am so grateful for your work. There are many excellent science educators on CZcams but your thoroughness and uninhibited passion set you apart. Your videos will play a part in my child’s education.

  • @jimdecamp7204
    @jimdecamp7204 Před 2 lety +25

    Great video! I am an EE and took a power systems course as an undergraduate, but I never appreciated this history. Thank you so much!

  • @l00k4tstuff
    @l00k4tstuff Před 2 lety +6

    Thank you for the full history. In the US, so much is US-centric, other contributions being brushed off as inconsequential. It's good to know the full history of technological development when trying to understand the technology.

  • @jimprice1959
    @jimprice1959 Před 2 lety +50

    Kathy - A very informative video. I love the history and reasons behind what we use today. I used to be a volunteer at the Folsom Historic Powerhouse in Folsom, CA. It was built in 1995 and we told our visitors that it was the first long distance 3-phase powerhouse in the US. It was built just a bit before the Niagara Fall powerhouse was put online. Niagara used Westinghouse 2-phase generators. I believe that GE got the power transmission contract to Buffalo and used Scott-Tee connected transformers to convert to 3-phase. It's interesting that the Folsom powerhouse has four 3-phase generators and used 12 wires to send the power 26 miles down to Sacramento. This was because the original governors were not stable enough to allowed the generators to be synchronized. The AC was converted to DC in Sacramento with M-G sets and then paralleled in order to power streetcars. The change to Lombard governors in around 1906 allowed the paralleling of the generators. Folsom used GE generators. I believe this was because the Livermore Brothers used financing by GE in order to build the powerhouse.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +15

      That is fascinating! I read somewhere, I think Allerhand, A “The Earliest Years of Three-Phase Power” Proceedings of the IEEE vol. 108 (Jan, 2020), that Westinghouse lost out on the Folsom gig because he refused to use 3-phase! It is fascinating to me that Westinghouse was so advanced and adventurous with AC versus DC and then so resistant to 3-phase.

    • @jimprice1959
      @jimprice1959 Před 2 lety +10

      @@Kathy_Loves_Physics As a Professional Control Systems Engineer, and powerhouse docent, I'm familiar with some of the older technology but never learned much of the history. Thanks for combining the two in an interesting way.

    • @triggerfish6619
      @triggerfish6619 Před 2 lety

      Hi Jim,
      Well now I'll have to visit, if still open, I'm in Citrus Heights and driven by often. Thank you for reminding me of fascinating things right near me.

    • @angelstevens2782
      @angelstevens2782 Před 2 lety +1

      @@Kathy_Loves_Physics Follow the money trail where a reason might be for this (his) reluctance.

    • @pliedtka
      @pliedtka Před 2 lety +2

      My sis lives in Orangevale. The first time I was visiting years ago and biked on the bike trail along the American River I noticed the 'strange' building. Then I found the web site about Folsom Power Station. Now I recognize the face of the man who runs the site - very informative, and big thank you. I had no clue it's one of oldest hydro power houses in North America.
      As for the 3 phase system the one used in Europe (at least in Poland and German speaking countries) is a bit different from North American, that most of the buildings like farms, small shops, receive 3 phases 380V, in order to run 3 phase motors equipment. Most new houses are also 3 phase ready. No need for strange rotary phase converters or transformers in order to run lathe or milling machine in garage ;) - thanks to Dobrovolski and AEG. I guess two phase residential system is cheaper to build and that is main reason it remains in use until today. BTW, in Canada from time to time I see 230-240V European single phase devices run from 2 phase system: other than speed in case of motors, no real issues such as overheating.

  • @TCPUDPATM
    @TCPUDPATM Před 2 lety +4

    Kathy, I’m brand new here, but the research and delivery of information is nothing short of AMAZING! I love that you don’t waste our time with wasted B-roll videos and other stuff. Your information and expertise is why we are here.
    Thank you, Thank you, Thank you!
    (One for each phase :P)

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +2

      You’re welcome you’re welcome you’re welcome… and thank you for the nice comment

  • @petereriksson4405
    @petereriksson4405 Před rokem +21

    No mention of Jonas Wennström who had a patented 3-phase motor in 1890. He also helped to create the worlds first commercial three phase transmission line in december of 1893 (Hällsjön - Grängesberg line). His inventions helped found Swedish ASEA, that later became ABB

    • @LucIan-er2ir
      @LucIan-er2ir Před rokem

      it depends of which sponsorig have 🙂

    • @mikerosoft1009
      @mikerosoft1009 Před rokem

      So who original invented 3 phase? Dolivo Dobrowolski or Jonas Wennstrom?

    • @suryahitam3588
      @suryahitam3588 Před rokem +3

      To my shame I had never heard of either Jonas Wennström or Mikhail Dobrovolsky. Both of their names should be up there at least with Edison or Tesla.

  • @coolcat23
    @coolcat23 Před rokem +9

    You always create exactly the right mix between illuminating personal motivations and technical background that makes following the subject not only a breeze but very enjoyable.

  • @edshave
    @edshave Před 2 lety +4

    Haven't watched this video yet as I've just discovered your channel and am slowly working my way through from the beginning. But I couldn't wait to let you know, I absolutely love both your content and style. You make it look easy but I know an awful lot of work goes into each one. Thank you so much for taking the time.

  • @itsevilbert
    @itsevilbert Před 2 lety +21

    8:57 Thank you, great video as always. I can remember long ago asking (pre-internet) who created this crazy star delta stuff (which is brilliant) - now I know Mikhail Dolivo-Dobrovolsky.

  • @petermacinnes5313
    @petermacinnes5313 Před 2 lety +7

    I like two things about this channel.
    1) The willingness to have a balanced view about history,
    eschewing the common practise of fixating on just
    the well known players (ie Tesla/Edison etc) whilst
    ignoring the contributions of others who were pivotal
    especially from a practical perspective.
    2) The presenter - Kathy, you are just so damn watchable !

  • @eepower
    @eepower Před 9 měsíci +3

    Your contribution and work to link history to science certainly make us well informed. Thank you for making these videos.

  • @buenosairesam
    @buenosairesam Před 2 lety +8

    I've been binge watching your videos the whole week. They are entertaining and the knowledge sticks, is so much easy to remember who did or discover what, when put in context. Plus your love for the subject shows at every second. So glad I found your channel

  • @edcooper5841
    @edcooper5841 Před 2 lety +10

    Wow! What a brilliant person and a great speaker. Looking forward to your book. I have been an electrical engineer for 45 years and didn't know the connections Kathy made with the history. How could you not love math, science, and engineering?

  • @SH-th4wy
    @SH-th4wy Před rokem +1

    I really like listening to someone who is so comfortably versed explain a topic. Thank you.

  • @straighttalking2090
    @straighttalking2090 Před rokem

    Love Kathy's enthusiasm. Didn't think I would watch a video on this subject to the end but she carried me to it. Well done.

  • @walteralter9061
    @walteralter9061 Před 2 lety +7

    As a Tesla fan for a lot of years, this was a real eye opener. Great research, great deliver and graphics. Beers on me.

  • @OneShotOT
    @OneShotOT Před 2 lety +16

    Just stumbled across your channel, the algorithm picked a good one for me! You do such a great job laying out the step by step defining events that lead to great breakthroughs. Loved your demonstration setting fire to alcohol by pointing to it! Keep up the good work. I'm sure you'll keep growing your channel.

  • @dougdoug2165
    @dougdoug2165 Před 2 lety

    Thank you for your video. You do an amazing job of tying loose ends together. When one gets more pieces of the puzzle fitted it make it much easier to comprehend the subject.

  • @georgestyer2153
    @georgestyer2153 Před rokem +1

    Thanks Kathy...great reserch..loved every minute

  • @richardsleep2045
    @richardsleep2045 Před 2 lety +6

    Wow these stories are always more complicated than one hears. Thanks for telling me about the amazing contributions of Dobrovolsky et al. There's such a lot of Tesla hype ;) Great stuff, subscribed, thanks.

  • @rdkeyser
    @rdkeyser Před rokem +4

    Great video, Kathy! I, too, stumbled upon this video while browsing something unrelated. (Thank you Google!) Previously I had a vague understanding of the 3-wire, 3-phase system, but now I see it clearly. The history is fascinating, as well. Thank you for presenting such an interesting lesson.

  • @mikelevero
    @mikelevero Před 2 lety +1

    That was so well explained. Congratulations on your exactness and concise message

  • @RCRadioShow
    @RCRadioShow Před 6 měsíci +2

    Like most American electrical engineers I learned that Tesla invented 3-phase motors and generators and never heard of Mikhail Dolivo-Dobrovolsky. Nice to hear the real story. It is interesting that it never occurred to the great Tesla that he could eliminate three of the six wires since the phase currents vectorially added to zero. Of course Tesla probably never had the advantage of mathematical tools like phasors. Also interesting that the great AC-DC wars fought between Westinghouse and Edison were fought with the wrong polyphase system (2 phase) and the wrong frequency (133 Hz). The better AC system eventually won out of course.

  • @garryclelland4481
    @garryclelland4481 Před rokem +10

    Kathy thanks so much for putting this up , ive been in electrical / mechanical engineering for 40 + years and you've taught me stuff i did not know ( i double checked ) , thanks for putting me right , liked and subbed , thanks again .

  • @mikesellers1879
    @mikesellers1879 Před rokem

    Excellent information !
    Many thanks Kathy !

  • @TimothyWorel-xj9he
    @TimothyWorel-xj9he Před 4 měsíci

    Very interesting video. Thank you for explaining the concept so simply.

  • @gullenator1
    @gullenator1 Před 2 lety +34

    Great stuff! There’s a lot of misinformation overhyping the achievements of Nikola Tesla recently. It’s nice to see somebody examine his contributions more objectively. He was certainly a great visionary, but the fact that he has a unit in the SI system, while Maxwell does not, is absurd.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +9

      I agree. Did you ever hear a quote about Maxwells laws from Richard Feynman where he said that it was the most important thing to happen in the 1800s and the Civil War pales in comparison? It’s a good quote

    • @lawrencedoliveiro9104
      @lawrencedoliveiro9104 Před 2 lety +5

      Worth pointing out, the Maxwell unit came first. The one named for Tesla came later.

    • @andrew_koala2974
      @andrew_koala2974 Před 2 lety

      gullenator1
      'Some one' - NOT somebody
      You will find every'body' in the cemetery
      A BODY is a DEAD entity - {Latin} CORPUS - from which derives the word CORPORATION
      - which is a DEAD entity and should always be written in ALL CAPS
      a BODY is a DEAD entity - {Latin} CORPUS - from which derives the word CORPORATION
      - which is a DEAD entity and should always be written in ALL CAPS
      'One' is unique
      'One is alive'
      understand that there has never been 'one' like you before you were born
      and there will never be another 'one' like you after you are DEAD.
      You are 'one' of a kind ---- but.. Every'body' is the same.
      Rotten and stinking after four days
      -- Your third-world education system failed you - (By deliberate action)
      And you failed to educate yourself.
      Learn the subtle differences.
      Also learn the difference between
      APPLE and Apple
      TESLA and Tesla
      ON and on
      TOYOTA and Toyota
      ARMY and Army
      NAVY and Navy
      And many others that sound the same but they are NOT THE SAME
      The problem here is that you and the majority were programmed to be ZOMBIES
      - ZOMBIES have eyes but cannot see - ears and can not hear
      The Programming - Indoctrination and PSYOPS has been largely successful
      in dumbing down the population

    • @sasamladenovic6120
      @sasamladenovic6120 Před 2 lety +1

      Maxwell have he's honorable name for famous equations... This is a lot more than SI unit.

    • @Trucmuch
      @Trucmuch Před 2 lety +1

      @@sasamladenovic6120 Having an equation you came up with named after you is pretty normal and has nothing to do with having a unit named after you which is a way of honouring you. It would be like saying, yes, it's a shame there is no street named after this author but all her books are named after her. Of course, her books are her books. It doesn't explain why no one thought she deserved to have a street named after her.

  • @tomsayen9295
    @tomsayen9295 Před rokem +1

    I really enjoy the way you explain and present. I'm glad we have you on You Tube as a lover of physics and history.

  • @jdillon8360
    @jdillon8360 Před 2 lety

    Great video Kathy, thanks for sharing your knowledge with us!

  • @donaldchasedgc4935
    @donaldchasedgc4935 Před rokem +18

    Hi Karhy, I'm glad to see someone has finally created a channel around the history of physics. My name is Donald Chase, and I have worked in the electronics industry for 40+ years. I thought of doing the same thing that you are doing, but never got around to completing the work when I realized how much work it would take to put all of my knowledge into writing. I love the way that you are doing this. You kind of remind me of Carl Sagan in how you explain the subject so almost anyone can understand it.

    • @ronjon7942
      @ronjon7942 Před rokem +3

      Donald, please, reconsider. What better way than this to share your knowledge (40 years is a long time, a lot experience), and also to leave a legacy? I don't think you can reasonably not do this until you've picked just one thing, write, and then share it with us. Only then can you say no to the re. Yeah, you're right, writing about 40 years of experience is overwhelming, hundreds of videos. But just one? Surely you could do just one. There's a definite need for you to do this.

    • @christophervallejo9838
      @christophervallejo9838 Před rokem

      Even if it's a voice over with pictures explaining, because I'm camera shy can't focus right lol

  • @flyingaround3
    @flyingaround3 Před 2 lety +12

    Kathy, very good job, ("dobro") on historical popular facts about electricity and basic principles on how it works.
    I do agree that many science giants (known and forgotten) on which sholders Nikola Tesla was "standing" to provide to hummanity the most efficient AC motor, should be noted in schools books. In Canada elementary/high schools only Edison is related to electricity in general not even Tesla.
    James C Maxwell is regarded as a founder of the modern field of electrical engineering and sure in high schols he should be considered as one of 3 the greatest physics scientists in addition to Newton and Einstein.
    Regarding Tesla, who helped you with your "eyes openning" facts agains him and being "Tesla nuts victim" to increase your You Tube chanell profit 🙂, you proved in the conclusion of this video with two papers: Nikola Tesla's 3 phase AC patent dated 1 May 1888 and Dobrowolsky's 3 phase AC patent dated 4 March 1890, that Nikola Tesla was the first and the most important 3 phase AC motor inventor and "gold winner".
    Thank you and keep up doing good work!

  • @HateClickBait
    @HateClickBait Před 2 lety +1

    This stunning, enthusiastic and informed woman just blows my mind. Her knowledge and her enthusiasm for explaining things just left me with my jaw dropped in my eyes wide open listening to her. No I want to know more about electricity.

  • @cemprotecta
    @cemprotecta Před 2 lety +2

    An amazing story, Kathy. Thanks for briging this topic out and explaining it in such an entertaining manner. I hope to see the release of your forecoming book very soon! Subscribed already!

  • @surendraraju5754
    @surendraraju5754 Před 2 lety +25

    Dear Kathy, Thanks so much for your amazing compilation of videos on the history of science. I understand that the amount of research that goes into making these is immense. Keep the great work going!! Glad that I came across your channel.🙏

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +3

      Thank you so much for your kind words.

    • @colmcillegardner2144
      @colmcillegardner2144 Před rokem

      One of my buddies in HS in 1964 and I built a 12v DC motor from nails and Cu wire for Science Fair. He went down in Vietnam January 1970 as a helicopter Army Warrant Officer. 58,479 brothers and sisters never made it back. May they rest in peace.

  • @andyfeimsternfei8408
    @andyfeimsternfei8408 Před 2 lety +5

    Check out the Lower Pelzer hydroelectric power plant. It went online in 1894 and still in operation. First AC powered textile plant with a 3.5 mile 3300v transmission line. Three 750kw units, one 250kw and one 1100kw. The first four were designed and built by GE and specifically Steinmetz at Mechanicsville. Four units have stationary magnetic poles with rotating AC armature and three 3300v slip rings. I believe this to be the oldest continuously operating power plant in the world.

  • @peters-adventure
    @peters-adventure Před 2 měsíci +1

    I'm glad to discover your channel! I wanted to understand 3-phase to discuss with my son who does theater lighting. This video helps make sense of electrical distribution and evolution. I liked, subscribed and plan to view more episodes. I love your enthusiasm! Thank you for the research and well organized presentation.

  • @BBQDad463
    @BBQDad463 Před 2 lety +1

    Thanks for this eye-opening and highly informative video. I do not recall ever having heard of Mr. Dolivo-Dobrovolsky prior to watching this video. Keep up the great work!

  • @tomschmidt381
    @tomschmidt381 Před 2 lety +34

    Great history lesson, I was under the impression Tesla was the first the appreciate the theoretical advantage of 3-phase AC and worked with Westinghouse to popularize 3-phase AC in the battle of the currents. I had not realized there was a 2-phase and 3-phase school early on or of Mikhail Dolivo-Dobrovolsky tremendous contribution. You have shown, as usual, the development of practical poly-phase power distribution was much more complex.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +9

      I’m so glad you liked it. Frankly I think the majority of us thought that Tesla pushed three phase in the war of the currents, as that is how the story is usually told.

    • @susilgunaratne4267
      @susilgunaratne4267 Před 2 lety +14

      All this misleading facts about Tesla is due to the erroneous social media posts. Now they have created a cult around him.
      I have written many time against this blind veneration of Tesla & pointed out the importance of Dolivo- Dobrovolsky.

    • @pansepot1490
      @pansepot1490 Před 2 lety +7

      @@susilgunaratne4267 the populace loves a simple story of a hero to worship. The actual complex and nuanced reality of many people contributing to progress is too difficult to digest. Kathy’s essays are exceptionally good at putting things into the right perspective.

    • @susilgunaratne4267
      @susilgunaratne4267 Před 2 lety +3

      @@pansepot1490 Exactly that's how people turn in for the hero
      worshiping to please their mind what ever the reality.

    • @democracyforall
      @democracyforall Před 2 lety +3

      She went to the wrong uni. Ha ha. AC was first discovered by tesla and this is how electricity was spread further and the wholeworld knows about this. The rest is the people were playing with the AC created by tesla however they did not know how to work it out at all ha ha so tesla once again went ahead and did it. Thus he is the founder of ac , and that ac was simply because electricity could now be transported further after that comes all these stories but the people who were trying to further tesla work could not do it ha ha so he did it all.

  • @Debraj1978
    @Debraj1978 Před 2 lety +3

    I work on 3 phase field oriented motor control and hence pretty much into 3-ph for past 18 years or so. But have never heard of "Dobrovolsky".
    Thanks for the great video.

    • @placiduzzu
      @placiduzzu Před rokem

      Hey Debraj, nice to see you around. I subscribe to your comment.

  • @markarca6360
    @markarca6360 Před 9 měsíci +2

    Westinghouse Co. is still operational today, manufacturing electric meters, and their biggest competitors are GE and Itron.

  • @1945jlee
    @1945jlee Před 2 lety

    Wow, clarified that mystery for me...!!! Love it Kathy!

  • @ktloz2246
    @ktloz2246 Před 2 lety +11

    Tesla is the man, he had patented 2 and 3 phase motors way before Dolivo started the work you talked about.

    • @Spiegelradtransformation
      @Spiegelradtransformation Před 6 měsíci +1

      Really. Your speech is just Wordscience.

    • @Itzzmeagain28
      @Itzzmeagain28 Před 4 měsíci +4

      Did you NOT watch the video?? Smh. 😂😂😂

    • @jeffrey1312
      @jeffrey1312 Před 2 měsíci +3

      I was a huge Tesla fan when I was young. Later I found that almost all of what I knew was wrong. It makes me sad that I was mislead for so long.

  • @in2minutesorless64
    @in2minutesorless64 Před 2 lety +20

    You're a great editor. Thank you Kathy for all your hard work and diligence! What an informative video. Keep it up!!

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +4

      Thanks 😊

    • @sethlavinder
      @sethlavinder Před 2 lety +4

      @@Kathy_Loves_Physics I absolutely agree! This is my first time here! I’m feeling very informed on a subject I happen to find very interesting, you have a very natural gift for teaching! I will be back for more!

  • @ronsnow2015
    @ronsnow2015 Před 2 lety

    Great video, enjoyed. Your presentation was also great. Thanks for posting.

  • @cajun3197
    @cajun3197 Před rokem

    Really glad I found this channel. Great videos!

  • @pasixty6510
    @pasixty6510 Před 2 lety +11

    Another great video…again! Thank you! I went to grammar school in Lauffen, from where the first 3 Phase long distance power transmission was made and I am happy that you pay so much attention to the meaningful experiment of those brave engineers to transmit huge amounts of power over more than 100km. I can say that much of the electric history is still alive. There still is a water turbine running in the place where they had run it then. There is an ‚Oskar von Miller Street‘ running down to the cement factory. The factory still exists and AEG, the firm Dobrowolski worked for, still exists, as well as Brown‘s firm, former BBC (Brown Boveri Cie), today ABB (Asea Brown Boveri). All of them managed to be enough innovative to make it into the 21st century.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +3

      Wow that is so cool.

    • @bpomowe224
      @bpomowe224 Před rokem

      @@Kathy_Loves_Physics , ASEA claimed to have the first *commercial* three-phase long distance transfer system up and running by 1893. Perhaps worth looking into how they fit into the grand scheme of things?

  • @aramboodakian9554
    @aramboodakian9554 Před rokem +5

    Kathy I love your videos, love how you love physics and history! There is more to be learned here than meets the eye and ear. Your passion and enthusiasm for the subject is infectious!

  • @bookoobeans
    @bookoobeans Před 2 lety

    Thank you Kathy! Outstanding presentation and research as always. Love your channel.

  • @Thomas-pq4ys
    @Thomas-pq4ys Před rokem

    I've worked in industry as a maintenance technician. I've wired a lot of 3 phase equipment.
    Although this video helped, I still don't fully understand 3 phase.... The person who trained me did explain a bunch, with a VOM, and how a single phase motor can run off of 2 legs of 3 phase. I also know well enough to just jog newly installed equipment to make sure it is rotating in the proper dorection. If not, just switching 2 of the 3 wires, it will ne corrected. I'm still baffled by it all, and proclaim myself a mechanic more than an electrician. Even 3 wire 220V in a home is a bit of a mystery... but I just installed 220V outlets for my welders... and everything works fine.
    My home is in need of a pro electrician. When they show up, I will pick their brains...
    Great video.... and thanks.

  • @jerrypender9019
    @jerrypender9019 Před 2 lety +4

    This was an outstanding presentation, and had me riveted to the screen for the entire time, which seemed more like 3 minutes than the actual time. I had no idea that the evolution of the electric power design was so complex, with so many players.

  • @FlorinSutu
    @FlorinSutu Před 2 lety +3

    Very interesting. Here I learned some things for the first time.
    And that comes from a guy who learned in university how to design electric motors, electric generators and electric transformers.
    The teachers told us in university about Mr. Dolivo-Dobrovolsky, and he was very shortly mentioned in specialty books, maybe because I graduated in Romania.

  • @teksight9714
    @teksight9714 Před 2 lety +1

    Wow. Really great video. I have a short attention span and get bored easily but I couldn't stop watching this story and the exciting way you told it. Thank you. I learned a lot.

  • @riquecube7579
    @riquecube7579 Před 11 měsíci

    This (your) video presentation opened my eyes on how little I know of the other Brilliant Engineer who made our electrical world as it is today . . . Mikhail Dolivo-Dobrovolsky!
    I am a retired Mechanical and Electrical Engineer. Had work in Electrical Power Generating and Distribution company for 30 years. I am aware of Technical accomplishments and contributions of Edicon, Westinghouse, Steinmetz and Tesla and the involvements of financiers J.P. Morgan et al.
    Never too old to learn. Thank you for your wonderful educational presentation.

  • @reconglobal1311
    @reconglobal1311 Před 2 lety +3

    Kathy, I really enjoyed your videos. I travelled to the UK often 30 years ago and, for lack of anything other than BBC on TV, watched James Burke's "Connection" and it became on of my favorite shows. Your show delivers that same mix of education, technology, people, and most interestingly the times and intrigue of the era that gave us the inventions we know today. Thank you.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +2

      I love the show James Burke “connections” and it is a very big compliment to tell me that I remind you of him. Thanks

  • @PlayNowWorkLater
    @PlayNowWorkLater Před rokem +3

    That was fascinating! I love your passion for history and electricity! And, you are capable of delivering this message like a University professor. I’m sorry, I haven’t checked to see what your creed are, but I loved this and it took me back to some of my favourite classes and professors whilst I attended University. It is rare for a CZcams video to be so engaging without a tonne of video editing. Your ideas and flow of content are concise, and engaging. Thank you for doing what you do. So looking forward to checking out your other videos.

  • @shahalammuhammedulla
    @shahalammuhammedulla Před 8 měsíci

    Excellent video. Thank you very much for the work you did. ❤

  • @petersvancarek
    @petersvancarek Před rokem +2

    But but but but... TESLA!
    Great to see a piece of real history and not what tesla fanboys are pushing forward as gospel.

  • @TheEvertw
    @TheEvertw Před 2 lety +8

    Great exposition!
    Personally, I believe one key advantage of the 3-phase system over all other systems is that not only is the summed current zero at all times (which a two-phase, 180 degrees system also has, or a 4-phase system), the power transmitted over the wires is also constant at all times (assuming a linear load). This means there is much less vibration in 3-phase systems compared to other systems of similar power, allowing much lighter construction.
    Contrast e.g. the noisy, vibrating hand-drill operating on 1 phase for a measly 700W, with the near-silent operation of a 3-phase motor. This is because the power delivered to that drill varies between 0 and almost 1000W, 50 (or 60) times per second.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +4

      Good point

    • @joee8417
      @joee8417 Před 2 lety +2

      @@Kathy_Loves_Physics That hand drill is not using a 3 ph motor . It is using a "brushed" 'universal motor'. No where near the same. Also the brand and the price range of the drills vary immensely. A commercial drill has a commutator with many small bars vs a 'homeowner" drill which has a few larger ones. Much rougher and less efficient. Properly designed large dc motors are quite smooth and have much more torque that ac motors. The downside is maintenance. The new ac drives are catching up but if you need 300 percent starting torque, a wound rotor dc can't be beat. I'm retired now, ex Elevator mechanic. A humorous note, as they change out the older DC drive elevator systems, the power bill just went up. As the elevator slows down the mg set rpm changes from 1725 rpm (60 cycle 3 ph incoming) to 1875 rpm. As it slows down it pumps power back into the grid and the building draws less thru the meter. As long as there is not to much idle time the parasitic losses aren't too bad. The static drives all have resistor banks with fans to dissipate the heat generated by slowing down the load. Now the new code compliant air conditioned machine rooms have to have the tonnage for the load. Lol Joe

  • @ronkirk5099
    @ronkirk5099 Před 2 lety +7

    As an engineer (retired) I've always been interested in science and technology history. Thanks for bringing to our attention some of the lessor known, but very important contributors to developing the electrical systems of our modern world.

  • @alexkije
    @alexkije Před 2 lety

    Fantastic story! Thanks for sharing! Very well told.

  • @jacoblf
    @jacoblf Před rokem

    Awesome presentation. Thank You.

  • @rickgilbrt
    @rickgilbrt Před rokem +5

    Thank you, Kathy. I'm a chemical engineer, and I find the history of science and engineering as the technology itself. I had not heard of Dovrowalsky or his contributions to 3-phase power.

  • @mototransistor6790
    @mototransistor6790 Před 2 lety +6

    My goodness, your work is BRILLIANT. Having done quite a lot of research myself to separate the facts from the myth regarding Tesla's achievements it is so refreshing to find objective and data based content such as yours, and so well done. It is a breath of fresh air under a sky polluted with lies and misinformation. I only wonder if it could be possible to discuss the contributions of Jonas Wenström to the 3 phase system. Thank you and congratulations.

    • @Kathy_Loves_Physics
      @Kathy_Loves_Physics  Před 2 lety +4

      Thank you so much. I am sorry that I did not talk about Jonas Wenstrum who really was an important early inventor of three phase except that he didn’t get the opportunities that Dolivo-Dobrovolaky got. I mostly didn’t mention him because it felt like too complicated a story already. Still, I’m sorry about that b

    • @RegebroRepairs
      @RegebroRepairs Před 2 lety

      @@Kathy_Loves_Physics Yeah, he died in 1893, the same year as ASEA finished their first commercial 3-phase power station. He seems to have gotten the exact same idea independently, but AEG seems to have been just a little bit ahead of ASEA.

  • @RockPolitics
    @RockPolitics Před 2 lety

    I rarely ever subscribe to channels. This one was an easy exception. Very nice work in gathering facts, and putting them into perspective. The significance of three wires vs six for power distribution cannot be overstated.

  • @greenbudkelly2820
    @greenbudkelly2820 Před 2 lety

    Wonderful, informative video delivered with passion and enthusiasm

  • @erikziak1249
    @erikziak1249 Před 2 lety +9

    Finally a video with full and correct information, with citations as well as explaining the "big picture" behind major decisons as well as historical/political context. I knew that Tesla did not invent 3 phase 3 wire power transmission. Despite his genius, he missed this one crucial part.

    • @radiomellowtouch
      @radiomellowtouch Před 2 lety

      Now I’ll remember: 3-phase 3-wire Dobrovolsky, 3-phase 6-wire Tesla. I’ve always taught that the world owed a lot to Tesla.

    • @marteng55
      @marteng55 Před 2 lety

      I think by then he was conceptualizing wireless transmission.
      As far as Tesla was concerned the polyphase transmission system was solved, no matter the number of wires.

    • @awancah7309
      @awancah7309 Před 2 lety

      @@marteng55 wireless is tesla imagination to reduce 6 wire..

  • @woodydameron5561
    @woodydameron5561 Před rokem +3

    Really interesting and explained so well!! All of those guys were geniuses - where would we be without them? 🤔