How an electric locomotive works…
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How an electric locomotive works…

September 9, 2019

Electric locomotives have been providing hauling power for trains since 1837. Unlike steam and diesel locomotives, electric locomotives do not carry any fuel or energy source. The energy that drives them may be located hundreds of kilometers away from the locomotive itself. Electricity produced at a distant power station is conveyed to the locomotive through overhead catenaries. An electric locomotive is essentially a box full of transformers and semiconductors. A pantograph collects electricity from overhead wires and transfers it to a transformer, which sets the electrical power to the desired voltage. A connection with the axle brushes completes the circuit. From the transformer, the alternating connect drawn from the overhead wires is transferred to a main rectifier which converts it to direct current. The main and auxiliary inverters than convert the direct current into three-phase alternating current. The three-phase alternating current powers the traction motors, which then drive the wheels. For the traction motors to efficiently drive the wheels, many small but important components are also needed. Auxilliary inverters and rectifiers power these smaller components. Transformers and rectifiers produce a lot of heat and have to be kept cool. This important job is done by cooling fans which are powered by the auxiliary inverters and rectifiers. A compressor also powered by the auxilliary inverter, supplies air at the required pleasure to operate the pantograph. A battery provides the power for start-up operations and also supplies essential circuits. The battery is usually connected across the DC controlled supply circuit. Finally, the traction motors also produce a lot of heat and require cooling. The traction motors are cooled by separate cooling fans which also draw power from the auxiliary inverters and rectifiers. So, that’s how electric locomotives work!


  • Reply Lord Blackwood November 24, 2017 at 5:57 pm

    If AC motor is being used then why they are rectifying it?

  • Reply mritunjay kumar December 18, 2017 at 3:47 pm

  • Reply Dayanand Kamble December 20, 2017 at 6:59 am

    Thanks sir..

  • Reply Amit Kumar Ram December 21, 2017 at 5:59 am

    Nic vdo,thx Sir

  • Reply pardeep attri December 30, 2017 at 10:16 am

    nice video g

  • Reply Vishnu Charitra January 2, 2018 at 5:11 pm

    Kya aap ise hindi mein dubbed kar sakte ho.

  • Reply The Comet January 14, 2018 at 7:31 am

    3 phase ac motors are being used in P7 and G9 rest are 15250A type D.C. motors.
    be clear about your topic

  • Reply AKHILESH SINGH Chauhan January 21, 2018 at 4:28 pm

    Wrong, semiconductor are not used in Electric Locomotive Engine

  • Reply Nagaraj Kumar Kummara January 22, 2018 at 12:42 pm

    I have one doubt y we r using AC motor first thing we got an ac supply from ohe then we r converting into DC by using rectifier and the again we r converting into ac to the motors y either we use direct DC motors by using rectifiers or ac motors direct from transformers why we r using waste rectifiers it's lot of huge process , money waste for the rectifiers and one more thing in earlier studies I listen DC series motor r using I think it's in diesel locomotives and I think induction motors r using in ac traction locomotives is it right ???

  • Reply Kshitiz Sinha January 28, 2018 at 9:19 am

    in traction dc series motor is used right….so how come 3 phase ac supply from inverters is able to drive them???or are universal motors used nowadays??

  • Reply Logan DeMott February 3, 2018 at 6:49 am

    The wag 9 is the most powerful

  • Reply Jai Beniwal February 5, 2018 at 8:23 pm

    Why would anyone dislike an educational video?

  • Reply siva mandadi February 8, 2018 at 11:42 am

    I want so more information

  • Reply Joy Ronaldo February 10, 2018 at 2:12 pm

    Hi sir I do project about Indian locomotive steam engine, diesel engine, electric engine and train signals you have ane ppt about this 4 type of engine and signals pls send my mail it is help to my project each topic have 10 page [email protected] pls send before 14 Feb 2018 pls

  • Reply Amit Pandey February 12, 2018 at 4:22 am

    why do is again converted to 3ph supply???
    I only chat get that,please clear this doubt

  • Reply pasupathi krish February 26, 2018 at 6:20 pm

    good but need to clear conceptssomething deeply

  • Reply Rohit Nachnekar March 2, 2018 at 11:57 am

    Nice explained in approx 2 and a half min

  • Reply Madhavan S March 4, 2018 at 11:23 am

    As per my observation, electric locomotive trains needs high starting torque and variable speed at constant torque in any loads. these points are fulfilled by inverter based Ac drives. By the way i have seen resistor banks on top of the train to desipate the back emf of induction motors.Hence there must be used AC drive system as shown this video. AC to DC conversion is needed to switching semiconductor devices to achieve variable frequency and voltage.usually IGBT used to achieve this and converted into AC .

  • Reply विचारधारा March 11, 2018 at 5:57 pm

    how many motors used in locomotives ?

  • Reply Prof. Hector Holbrook March 28, 2018 at 8:51 pm

    Very good. Thanks.

  • Reply Subhendu sekhar March 31, 2018 at 5:49 am

    interesting but not that much.

  • Reply Opt Hacker April 11, 2018 at 8:54 am

    How many volts of electricity do the wire transfer to the engine

  • Reply Akbar Saleem April 30, 2018 at 3:59 pm

    Please make an video on the topic " HOW ENGINE STARTS"

  • Reply JungleYT May 14, 2018 at 3:04 pm

    PURE CRAP… You failed to explain how the circuit is completed … Once electricity is drawn off overhead, rectified and goes thru motor where is the circuit completed? I would think thru one of the rails???

  • Reply Ajay Pankaj May 24, 2018 at 6:20 am


  • Reply sunny mathew May 29, 2018 at 3:52 am

    I am locopilot

  • Reply Chandrahas Prajapati June 8, 2018 at 5:39 pm

    Indian Rail traction system is upgraded by 3 phase squirrel cage induction motor. So We direct give AC power to the traction motor

  • Reply R.S.K SHANKAR June 8, 2018 at 10:33 pm

    Hindi ma bolmakr

  • Reply DeeZanic June 10, 2018 at 8:25 pm

    How hard can it be.. you just press on and thats it..

  • Reply Sharif Abdul June 13, 2018 at 7:30 pm

    Axillary,pantograph and my ass

  • Reply MATHA SANTHOSH KUMAR SANTHOSH KUMAR June 19, 2018 at 1:42 pm


  • Reply MATHA SANTHOSH KUMAR SANTHOSH KUMAR June 19, 2018 at 1:42 pm


  • Reply Krutika Bagde June 25, 2018 at 8:22 am

    Please add some more info.

  • Reply Free electrical education June 27, 2018 at 11:08 am

    रेल के इंजन को फेज और न्यूट्रल कहाँ से मिलता है How to get phase neutral on locomotive railengine

  • Reply mayur chawde July 2, 2018 at 1:01 pm

    Hi there.i simply not get your last point which is related to compressor and transformer!? Sorry but I couldn't get it.

  • Reply Carlos Wilson July 7, 2018 at 11:52 pm

    Interesting. How is the motor speed varied. AC motors run at a speed determined by the frequency. Is this frequency varied by all that circuitry?

  • Reply bokka Padma July 16, 2018 at 7:32 am


  • Reply Mallikarjun G July 17, 2018 at 2:40 pm

    Which type of motor is used in traction? Ac or Dc..

  • Reply Mr. Sarvy July 19, 2018 at 5:58 pm


  • Reply Fari Raja July 28, 2018 at 2:53 pm

    in tirur 2012😊😊

  • Reply DREAM OF LOCO August 4, 2018 at 8:10 am

    wow! In the beginning of the video 0:6 – 0:9, GOOTY WDP 40 locomotive is there

  • Reply vignesh k August 8, 2018 at 1:52 pm

    Which is the power full engine

  • Reply Satyanarayanmurti Katta August 15, 2018 at 2:11 pm

    Normally household have main and neutral power supply. How EMU it works?

  • Reply Satyanarayanmurti Katta August 15, 2018 at 2:12 pm

    How the reverse mechanism work in EMU and diesel locomotives ie: going in reverse direction

  • Reply Shadow_of_STLKR September 12, 2018 at 6:48 pm

    "Thats how NEW electro locomotives works"*

  • Reply Bob Sergeyev September 30, 2018 at 6:14 pm

    shitty accent -_-
    learn how to speak english first please

  • Reply Natraj S October 3, 2018 at 6:28 am

    Simple and easy to understand

  • Reply hakeem harun October 4, 2018 at 11:43 am

    Anyone knows how the rod connecting to the elctric cable on top works? L

  • Reply Akhila Ramachandran October 25, 2018 at 1:45 am

    where the impedance mismatch occurs and how it mitigate

  • Reply A Postive Rider October 28, 2018 at 7:47 am

    ok thanks for ur info brow

  • Reply Diaz マルコ・ディアス鉄道好きMarco November 13, 2018 at 12:16 am

    I like this video

  • Reply mihindu1967 December 8, 2018 at 4:33 am

    The 1930s when electric locomotives came into operation were the days of vacuum tubes, and ultracapacitors were not even heard of or dreamt of during those days. Today in an age when ultra-capacitors made from curved graphene materials, are putting megawatts of power into small building blocks of powerhouses, is it necessary now for the locomotive engine to draw its power from overhead cables? Can't an entire train carriage hooked behind the locomotive engine, packed with several building blocks of ultra-capacitors storing millions of megawatts of power, drive the train for at least 500 km without the overhead cables? Well, couldn't such technology exist today?

  • Reply Anil Kumar. K December 20, 2018 at 2:29 pm

    25000VAC……!!!!! Is there any chance of lethal electric shock through the rails….?
    What are the precautions taken to prevent electric shock…..?

  • Reply Manoj Mudiya December 20, 2018 at 3:29 pm

    Why would we convert ac to dc at the rectifier

  • Reply Arunarunas December 21, 2018 at 3:23 pm

    From wer will take the negative connection…. Because the substation was providing positive connection… Which will be the negative

  • Reply Rohith Kumar December 27, 2018 at 4:05 am

    not at all cleara

  • Reply MUSICALLY GYAN December 28, 2018 at 4:08 am

    please tell me which animation software u use

  • Reply Sunny Kumar December 29, 2018 at 4:26 am

  • Reply E_404 December 29, 2018 at 8:53 pm

    I really wanna take one of these appart one day

  • Reply Sathishkumar Kuppan December 31, 2018 at 8:58 am

    Could you upload locomotives breaking systems

  • Reply DHARMABRATA SAHOO January 4, 2019 at 4:54 pm

    My question is that..the Traction motor mounted only with the engine wheel or all the wheels of the train?

  • Reply Paul Hojda January 6, 2019 at 4:35 am

    Wait, so the 9verhewd wires deliver ac power which gets converted to dc, which in turn gets converted back to ac… But why? Its makes no sense

  • Reply cobrasvt347 January 16, 2019 at 6:16 pm

    Wonder how often the brush's have to be replaced

  • Reply cobrasvt347 January 16, 2019 at 6:17 pm

    If it uses 3 phase why does it have brushes

  • Reply Mithra Manohar January 17, 2019 at 11:38 am

    How MEMU & DEMU works?

  • Reply Cigmorfil January 17, 2019 at 9:20 pm

    What about the third rail DC electric locos (eg the old class 73 BR locos that ran on Southern tracks)?

  • Reply Unik Express January 18, 2019 at 3:27 am

    Sir,You are simply defined it's topic.👍👍👍

  • Reply Abish Babu January 21, 2019 at 1:51 pm

    But… We cant see these power lines everywhere.. Why is that?

  • Reply praveen kandru January 25, 2019 at 10:21 am

    Supply line voltage is dc not ac. Dc can't be step down with transformer.

  • Reply Amuthan January 25, 2019 at 11:36 am

    Only one wire are touched to the engine from supply line then where it get other polarity?(is it get minus voltage from train ground?)

  • Reply Antony Thaliath January 26, 2019 at 8:32 am

  • Reply AOTian Rohit January 29, 2019 at 4:41 pm

    According to this video, from the transformer, the supply AC current is converted into DC by using rectifiers, and further it is converted into 3 ph AC using inverters. So here AC is ultimately converted into AC, then why the rectifier is needed?

    And my another question is that, is the supply AC is single phase or 3 phase?

  • Reply Garuda Penjunjung Kebenaran February 2, 2019 at 5:38 am

    The streetshitters accent

  • Reply Neil Dahlgaard-Sigsworth February 5, 2019 at 5:01 pm

    What about battery electric locomotives?

  • Reply George Ray February 7, 2019 at 11:28 pm

    Nice explanation

  • Reply MATHS JEE March 4, 2019 at 4:05 pm

    If we touch the rail tracks then do we feel shock ?

  • Reply Moses Joshua March 9, 2019 at 5:49 pm

    Very nice presentation! I like it!

  • Reply Bala P March 14, 2019 at 6:15 am


  • Reply Manohar Kuse March 15, 2019 at 4:38 pm

    Electric locomotive since 1837 …no way. May be he meant 1937??

  • Reply S U D H A N S H U May 30, 2019 at 5:06 am

    Why there are some long spaces in your speech lol 🤣

  • Reply Tahmim Chowdhury June 4, 2019 at 11:57 am

    Why 3 Phase?
    It wasting energy

  • Reply ali mowafak June 7, 2019 at 1:25 am

    and when we want to change the direction of travel , what must we do ? how can we that doing ?

  • Reply Qaterius June 30, 2019 at 8:04 am

    Why wheels don't kill us? When there is end of a circuit? 😀

  • Reply Motorhead Priyanshu July 7, 2019 at 3:13 am

    I wanted to know about this and here I got the perfect video to demonstrate the working of Electric locomotives.

  • Reply dr. merasmus July 18, 2019 at 10:48 pm

    Nooooo they use AC have you heard about Kando V40 the first AC locomotive

  • Reply naveen28723001 July 26, 2019 at 3:52 am

    By taking EEE can v join for railway..

  • Reply SHUELL BUGGS August 2, 2019 at 6:42 pm

    Why don't they use a single to 3 phase transformer and then directly give the 3 phase to the motors . WHY RECTIFIERS ???


  • Reply Debabrata ghosh August 27, 2019 at 6:23 am

    Where is neutral line??

  • Reply Dennis V Sinclair August 31, 2019 at 2:39 am

    Well done! Thanks!!

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