An induction motor can work as generator without modification. it need external power supply first. but when it reaches Above synchronous speed. it start generating power.
@@greatscottlab if you are going to try it with connected to grid then it will generate power at grid frequency (60 or 50hz) and if with capacitor bank frequency can be different.
"Me: Screams in mechanical engineer" it's always funny when people react this way... but i understand why more often than not stuff just has to work, no be perfect and beautiful. especially in a test setup
In my school I got a question can you explain. Q-) Electric shock is caused by_____. . Electric current . Electrical potential difference . Electrical resistance . Electrical energy (Note you can choose only one option) Edit: Correct answer = Electric current PLS EXPLAIN 🥺.
Edit : It's electric current because the amount of shock you get depends on the resistance and the supply voltage. It's I = V / R ( Ohm's law. ) Imagine you're connecting your 20 ohm resistor across 20 V. If your supply is current limited ( Constant Current / CC mode, ) the voltage will drop down but if your supply current isn't current limited ( Constant Voltage / CV mode, ) the current will remain high and could burn the resistor. And one more thing, DON'T BELIEVE THOSE " IT'S CURRENT THAT KILLS NOT VOLTAGE " CRAP THEORIES !!! Here's some videos to make you more understand the laws : ruclips.net/video/XDf2nhfxVzg/видео.html ruclips.net/video/DOMs7mYm_zs/видео.html ( skip to 8:29 ) Sorry before. I write these comments on 2 o'clock in the morning, so yeah :-/
you can turn an induction motor into a generator if you kickstart the magnetic field in the rotor by powering the stator at startup for a short time, this will generate residual magnetization which will self-excite the motor under load. i would love to see it in a video, thanks for the video 👍
actually it will require continuous reactive power. if it is connected with grid or capacitor bank it will take reactive power from it. otherwise it will not work.
@@greatscottlab I love this idea too, I need to make a pedal generator from a brushless washing machine motor to charge a battery+ultracapacitor bank pretty soon, ideally without opening up the motor
@@greatscottlab I think you should reconsider the magnetic assembly design and magnet polarities like I said in my other comment. Match rotor magnet poles with stator poles and also pole area. Do update us if there is any progress and about the process.
HA HA HA HA HA! Great point!!! I so the thumbnail, my first thought was "Great, A-Synchronous motor as a generator!" ... O_o and then he bought two !!!NEW!!! Induction-motors to prove he is wrong, OMG PS I'm not an electrical engineer.....
When we are able to admit our mistakes along the way of our progress,we are actually getting closer to the solution. We must not quit at these junctures. Our host in this video shares with us his downfalls and then the ultimate victory.Bravo. Also really like the handwritten detail for the ther side of my brain. Marvelous.Zippy
I think that the main problem you had here is the number of magnetic poles you chose. If the stator has p = 1 (1 pair of poles, or 2 poles) your rotor needs to have also 2 poles. In this case, if you choose 8 magnets, you can put 4 adjacent magnets with the north pole facing outwards, and the other 4 adjacent ones with the south pole facing outwards. Otherwise, for each phase, a EMF will be induced in each coil but they will not have the same phase, so you can get them totally or partially cancelled. If you go with the 2 pair of poles motor, you can do the same, but creating 2 pair of poles in the rotor also. You can do that with 4 magnets of alternating polarity, or with 8 magnets, but you need to have 4 pairs of adjacent magnets that are facing in the same direction (Just to be clear, if you check the polarity of each 8 magnets, you will have: N N S S N N S S).
he is replacing rotor with permanent magnets.reactive power will be required if magnetic field has to be created from supply. so here it is not required.
Sure. I meant he could keep the squirrel cage and just attache capacitors to the stator. I believe it's a simpler solution and possible to provide better results.
adding capacitor bank is a good idea no needs to modified any part of the induction motor dont tell me to add magnet to the rotor, then you are making the induction motor into synch motor
Thanks so much for taking the time to make this video. I am planning to make renewable energy for free as part of my retirement plan, and your experiments have given me a great insight as to how I should proceed. In scientific endeavour, failure is just important as success, which means you have saved thousands of other humans time and resources by making this video. :)
For a much better operations: a) the number of pole pairs of the stator should match the number of pole pairs of the rotor b) the magnets need to be stuck to iron on the inside of the rotor, so that the magnetic circuit has much less reluctance, meaning more magnetic field c) the air gap should be reduced as much as possible I think a and b together will already make the generator much more powerful.
Yeah, that distance between the magnets and the coils looks like a big handicap to the whole thing. The dipole magnetic field is falling off with r^3. Or do you see another reason why energy transfer here was so bad?
@@mdrolc The rotor need to be ferromagnetic to conduct magnetic flux better. Tight airgap and magnet back-iron will reduce reluctance of the magnetic circuit and inprove back EMF.
@GreatScott, you're brilliant! I kinda love that this video was a series of FAIL, and you went ahead and posted it anyway!! Thank you for sharing so that your learning experience can become OUR learning experience. And I will see you next time!!!
I’ve learned that you can use a capacitor to load the coils to generate a magnetic field to generate power and siphon off a bit to keep the field active.
Hi Scott, any Induction motor can work as a generator. It only needs to be fed with reactive power ( via capacitors while running isolated). You may need to modify some winding connections though and no, grid is not required.
im currently working on close to the same project. i just use a hoverboard motor/bldc as the generator. and it works great. Im also glad you uploaded the video anyway. always entertaining content!
Hi, you mentioned using a hoverboard bldc motor. I'd like to do it that way too. What does your setup look like? Do you also use a bicycle? what is your transmission from your drivetrain to your motor? Thanks in advance
Isin't the rotor basically just laminated metal? I don't think there are actual windings. When used as a motor it induces magnetism into the core which makes it spin because of the frequency change, and it lags behind a bit. There are some motor types that do have windings though then yeah you can add an excitation voltage. At least I think that's the case?
It didn't occur to me that an induction motor can't be used as a generator, due to the lack of magnets on the rotor... But I was VERY surprised that it still sucked when you added neodymium magnets to it. I guess it's down to the windings, like you said in the video. You learn something new every day!
It would be very difficult for a human to generate power with an alternator, about all a human can sustain for any time is about 100-200 watts, some may peak at about 500 watts for a short tine. But a alternator us in the 2kw range, it could be modified for less power, so you may as well use something more suitable!
If we take a convenient figure in james's sustainable range of 120 watts at 12 volts we get 10 amps. No magic can increase that. I'll assume that a decent car alternator is at least 80 percent efficient so thé max you can get is about 8 amps, nearly 100 watts. No point in paying for a higher power alternator, buy the most efficient one in spec and match the gearing to human pedalling speed, which can probably be done with standard bike gears. Probably already has. Buying the wrong device and gluing magnets to it to get one watt is daft. So yes, definitely, a decent car alternator unmodified is a good option, just arrange an appropriate gear ratio.
@@raykent3211 Hey Ray, I'm not sure where the 8 and 10 amp figures come from. I have personally seen a 120 amp alternator put out well over 100 amps when under load.
@@jamest.5001 I have used an alternator for a bicycle generator. I had to modify the electronics, but not the mechanics. If you run the field coil at a higher current than designed, you can run it at a correspondingly lower rotational speed. A bit of work with a PWM drive and flyback diode means that the current drawn by the field coil drive is only a fraction of that running through the coil itsself, making the whole thing reasonably energy efficient. You need a little power to start it, but get a lot of power once it's running.
I'm too working on convertion of an induction motor as a generator , but my application is as an flywhee energy storage system . We use the induction machine as a motor first to convert electrical energy to mechanical and then store it as moment of inertia. Then when we require it we use the induction motor as a generator this is usually achived by placing capacitor bank across the motor terminals to feed reactive power as someone mentioned . This will work with no major constructional modification to the machine.
@@karthikeyajavangula8423 I'm currently working a project where we compansate the low voltage ride through in winds mills by pumping the stored energy to the grid . When there is excess wind production the excess is stored in the flywheel and when there is a deficit it's discharged. Conventional storage devices are not that robust and are expensive as a wind mill may face lots of variation in a day.
Pretty nice work, dude! Thanks for the video! 😃 Question: what about trying with a vehicle alternator? After all, it's used exactly as a generator. 😉 Anyway, stay safe and creative there! 🖖😊
Car alternators work on a constant speed, its done by a governor... all this put together and you still have to reach the right speed... good option but not an efficient one
Try keeping a poll on your channel, so u get to know what kind of content your viewers like, maybe because of shifting in topics over a long time maybe u lost views. I'm just trying to help you, because u add a lot of effort to your video's and deserve more views. Great work.👍
the content of your videos SOOO GOOOOOOD your thicc denglish accent SOOOOO BAAAAAD i will now watch your videos muted and with subtitles on. thank you very much for the effort to put subtitles in! keep uploading, you have great videos!!
i'm very happy this video was made. I asked about this exact concept in the induction motor video and now i can see this is completely a waste of time. :)
Why the 3 output sine waves are in phase? I thought they have to be 120 degrees apart to give you maximum phase to phase voltage difference. May be it has to do with the number of magnets on the rotor compared to windings on the stator.
Absolutely, but it is NOT an induction motor. The difference is that the rotor in alternator has an electrical winding (coil) on/in it. At a guess it could generate up to 40 Amps at 14.2 volts, which is 568 Watts
The device doesn't check to see whether it's being spun by a piston engine, team of horses or a human. Yes it will work and be far better than what's shown here if spun fast enough. Gearing. The video is misleading because he takes some parts from an induction motor and converts it to a different device badly.
I build a bicycle generator once. I used the alternator from a car engine. The key was to rip out the alternator's built-in voltage regulator circuit and build my own one. Aside from being a bit more energy-efficient, it also let me adjust the output voltage and increased the rotational speed range over which the alternator was able to operate. Car alternators typically are 'backwards' generators. The field coil is on the rotor, and the power is generated on the stator. The voltage regulator monitors the output voltage and, through a simple feedback mechanism, adjusts the field coil current and thus the magnetic field strength to maintain the target output voltage as the load and rotational speed vary. My peak generating capacity was fifty watts, but I was only able to sustain that for a brief time. The limitation was biological: I'm just not in very good shape and can't maintain such energetic peddling.
There are cheap motorized bike kits that include a motorcycle chain compatible gearwheel with mounting hardware to secure it to the disc brake side of the wheel . I believe you can find that gearwheel outside of the motorbike kit
Hello! I am a big fan of your projects! I would like to add some things. An induction motor cannot generate its own voltage and it needs to be connected to the grid and to operate in negative slip in order to produce real power. Even if it is connected to the grid it needs to consume reactive power or else its voltage will collapse. You basically created a synchronous generator after adding the magnets. In this case the number of poles of the stator needs to be the same with the no of poles of the rotor. Also, maybe you need stronger magnets and smaller gap between the stator and the rotor and most importantly dont forget that the motor was designed for 50hz grid. Anyway, I love your experiments! Keep going! 🙂
The capacitor is providing the energy for the magnetic field. I learned a lot about this from a book using motors as generators. It is the cheapest generator an inductive generator.
I'm fairly new to this but I concur with many of the comments below. 1.) The distance between rotor and stator is too great. 2.) You are suffering a loss from friction and wobble 3.) Number of magnates, you can maintain the 2, 4, 8 orientation if you want but increase the time in those states by doing 2x8, 4x4, 8x2. For example shorthand 4x4 being 4S->4N->4S->4N 4.) Coverage, in this case a mix of 3.) and the length of the magnets. In your current setup it looks like only about 20% coverage Anyways, great video loved to see you work, looking forward to checking out your other videos.
A three-phase asynchronous motor basically IS a synchronous generator without any modification, it's the application in the circuit that determines whether you call it a motor and a generator. In some applications it does both, f.e. in modern trains when you want to accelerate the electronics send the three-phase voltage into windings, and when you want to brake a resistance is being applied instead decelerating the train (of course very simplified description)
Hey Scott, I did it once with a single phase induction motor, just using a capacitor. the tank circuit excited the motor than it worked. I used a 1/6 HP motor, and sucefully powered 8 fluorescent lamps powering the motor with a drill.
There is a device in common use called a rotary phase converter which uses a 3-phase induction motor simultaneously as a motor and generator to produce 3-phase power from single=phase power. Capacitors are used to start and run the 3=phase motor on single-phase power. After the motor gets up to speed, the other two phases of the motor generate power. These two phase are then combined with the single-phase input power to yield 3-phase power. This type of device is handy for operating 3-phase machine tools in a home shop where only single phase power is available. Rotary phase converters are being gradually phased out in favor of solid state variable frequency drives which also can synthesize 3=phase power from single-phase power although the resulting 3-phase power is a PWM waveform. The rotary phase convertor produces true sinusoidal 3-phase power waveform.
you can magnetize the rotor the start by using small amount of DC current through any of the winding for generating a voltage also for utilizing the output you have to place a three phase capacitor bank setup for stabilizing the output voltage, since voltages in induction motor as generator setups tend to collapse when subjected to change in loads. And if you have a constant value capacitor set the IMAG setup can only be used for a constant power output setup..
Dude, you're turning an induction generator into synchronous generator, great job 👍 How about making the shaft of the induction motor spins faster than its rated rpm, and connects its terminal in parallel with a capacitor in order to produce the voltage that you want. That would be great if you make a video this way. You're amazing 👍
You don’t need magnets to excite the magnetic field into an induction motor. Just add capacitors (rated for motor voltage e.g. ~2µF / 350V) in parallel to windings. So this is to deliver reactive power by swapping energy between coils and capacitor in this simple oscillator. If you spin up the motor, voltage will rise quickly due to remanence. But you have to cut off the load with a triac to prevent the field to collapse. If the voltage of self-excitation is high enough, load can cut in... you need a resistor in gate of triac to cut in load at above 50V. Worked great with my 1.5kW wind turbine. Your approach didn't work because the magnetic field induced by the permanent magnets were very weak compared to several amps within squirrel cage at self-induction....
Yeah, you need to feed both rotor and stator in order to work as a generator. They call it DFIG ( Double feed induction generator ) and it's widely used in eolic generation. Great video as always, greetings from Brazil 👍
some info. at :31, the presence of a Resistive load in the output circuit SCREWS up measurements and reduces the amount if lenz-related drag, in the genny.
@GreatScott!- There's a guy on youtube named Quint Builds who used rainwater as a generator. He has a good design (DIY), does a lot of testing, and may be worth looking at for ideas on a generator. It should work for your bike project as well. Love your content!
Great video! I've always wanted to make a bicycle generator but using a car alternator to charge a car battery. I bet you could make a great system with that.
I made something like this. Changed the three-phase motor into a three - phase generator. It was an old washing machine motor. I did it by rewinding it into a low-rpm 12 pole machine. The rotor, a squirrel-cage type was milled into a 12-side symmetrical polygon, one side for a neodymium magnet. 12 magnets were glued to the rotor with epoxy glue and laminated with glass mat and epoxy resin. The old winding was removed and I rewound this motor with an enameled copper wire with diameter of 1 mm. At ca 60 rpm it gives me about 8 V after the three-phase full bridge rectifier. It is easy to connect the buck regulator set to 5 V and charge the smartphone. This was absolutely not cheap and quick work, especially, that I had to rewind it twice (man learns by trial and error...). Phase voltage at 500 rpm is some 30 V RMS (it gives about 70 V after rectifier), frequency is 50 Hz. First, you should check how many poles has your stator winding and apply exactly the same number of magnets on the rotor. It is easy from reading a parameters plate on the motor: about 2850 rpm is 2-pole, 1450 rpm is 4 pole, etc. If you just put some arbitrary number of magnets on the rotor, without checking the type of winding - you will just loose time and work. Moreover, it you want low-rpm generator, you must rewind it with thicker wire, or you will get just a device to change mechanical energy into heat... The less rpm machine - the more iron, copper and magnets it needs for the same power as high - rpm machine. Roughly inversely proportional to RPM - 2 times lower RPM means 2 times as much copper, iron and magnets for the same power. That's why generators in big windmills have a gearbox increasing the RPM from ca 60 (propeller) to like 3000 (generator rotor), because low - rpm, directly propelled generator would be insanely HUGE at powers of the order MW...
The way it was described in the lectures that I attended is pretty much what the previous comment tells. With a formal clarification or two. You can use the asynchronous motor as a generator, when you have AC magnetizing, not DC that the permanent magnets represent. The terminology actually is that with BEYOND SYNCHRONOUS SPEED any asynchronous 3-phase motor will feed REAL power to the network, while consuming REACTIVE power from the network. The reactive power is what provides the alternating magnetic field. Another practical issue is that the motor is very critical to what is called air gap between the rotor and the stator. Consider that good soft magnetic iron conducts magnetic flux some 3 or more orders of magnitude (more than a thousand-fold) better than air. A 1 millimeter air gap resists the magnetic flux more than a 1000 millimeter path via the iron. I recall how a small stream was not a good proposition for a standard synchronous generator due to all critical controls required. So an asynchronous generator was installed and happily produced 200 kW power to the network. There was no need to synchronize the rotation speed to the existing power line frequency and phase. You just started the generator as a motor and then added more speed from the turbine to exceed the line frequency. The generator ran faster, if there was more water and supplied more power to the network. All that happened automatically, no speed controller needed.
The induction motor has to achieve super-synchronous speed to start generating electricity. That's then is called an induction generator which is used for power generation through wind energy.
@GreatScott! I think, you were wrong, when you placed the magnets in alternate order. You shuld place them to get the rotor with one side fully south, and the other fully north; becaus when you run the induction motor, that is the induced magnetic pattern in the rotor, not 8 south, and 8 north. If i were you, i would give a try to that setup... Correct me, if I am wrong
@@matthewmaxwell-burton4549 He stated the first motor is 2 pole and the 2nd motor is 4 pole. Reading the comments, you beat me to the answer. I posted that too, but wanted to see how many people here actually caught that error.
Use a cheap 120v DC treadmill motor like me. 100 watts is easy to generate, though, my output voltage is only around 45v. Still excellence for a power diode to a huge cap and a switching DC-down converter regulator from TI which will take in 75vdc through ~9vdc and output a select-able 12 through 24 vdc up to 10 amps. Though, to get the RPM up, I had to use my rear tire's diameter as a pulley to motor tiny pulley. Also, the flywheel on most treadmill motors was needed to smooth out the load and pedaling torque. Also, at least the treadmill motor I chose has no cogging!
That's the best solution....the only drawback is that he would have to peddle faster than the motors rated RPM to start generating electricity. Which is hard to do because once you past the slip speed resistence sets in even without a load
Recommendation .U can use24 v dc RO pump usually used in water purifiers these are usually consumes 1.5 amps at 24v dc and can act as a better generator..
Induction motor can work as induction generator when slip is negative,that can be done by either moving motor shaft faster than rated rmp or by decreasing supply frequency.it can only provide active power not reactive power, reactive power has to supplied from source.
thank you sir the information, i like your experiment, i love to do that but i have no time. but you did already, puting magnet to the rotor need only low rpm and created ac voltage . good job sir.
We used to have bike generators back in the 80's. It was a small device that picked up on the side of the rear wheel and made enough power to light the front and rear lights. Not very bright though from what i remember.
You can use a regular 3phasr induction motor as a basic generator by flashing a phase across a battery to magnetise the iron then spinning it with 3 motor run capacitors across the phase wires.
You missed the whole Asynchronous Generator. You somewhat match the inductive reactance of the SCIM to a 3 phase connected capacitor bank reactance to create a near tank circuit and the motor will generate nearly the same power as it is rated to put out. Don't mess with the rotor.
Or just take an alternator from a car and hook it up via a belt and easily generate stabilised 14.4ish Vdc and as many wqts your stamjna can handle. The second issue with asynchronous motar are that the voltage fluctuating quite a lot base of the load, synchronous motor are better choice but they're a hassle to work with because of the DC requirements IF I remember correctly. And as always, your videos are both entertaining and educational. //Cheers.
Nice work, Scott, i think that the problem is not the orientation of the magnets, or even the magnets, you can use just two of them (pretty big, obviously). Remember that the separation of the poles (on the stator) is made for generate a rotating magnetic field , the rotor will just act as a big magnet, if you want to generate power, with an inducton motor, i suggest, changing your rotor for an alternators car rotor.
Induction motor can generate electricity only if the slip of the machine becomes negative, that is if the shaft speed becomes greater the synchronous speed. But the machine needs reactive power to do this, which can be supplied from the grid or by connecting a delta connect capacitor bank at its three phase output.
You need a permanent magnet alternator or generator for that project. Bicycle lighting sets have used those for about a century, usually driving them from a roller against the bicycle tire. The rotor might work better with magnets mounted in a helical configuration.
There on internet is couple videos of people using 2 or 3 capacitors to convert 3 phase motor to one phase AC generator without any motor modification (google result of "AC 3 phase motor generator with capacitors"). To start generating it needs slightly more RPM than normally that engine runs. With that caps 3phase motor can run on one phase (with reduced start torque).
Hi there pal just watched your video on making the hand crank generator, which what I watched was absolutely amazing, from start to finish you should have your own business pal, thanks
To go from three phase ac to DC would require a decent full bridge rectifier and subsequent voltage and amperage regulation. 5v 500mA for standard USB charging. 5v 2A for tablet charging.
This video is really interesting. When an Induction motor runs as generator, it's called Asynchronous Generator and it happens when rotor speed is faster than synchronizing speed of the field, i.e. the slip is negative. I suspect if we normally run an induction motor from supply and than rotate the rotor even faster by providing more power to the shaft, our motor should generate and feed back to the supply. I'm interested to see if you can do such experiment and post a video on it. Induction motors are used in electric car and act like generator during braking resulting the braking power to be stored on cell (aka Regenerative Braking).
If you want it as a good generator with the niyodium magnets you have to change the winding obviously. You have wind it accordingly to a BLDC motor. So it will be a big BLDC motor and will generate a lot of energy.
An induction motor can work as generator without modification. it need external power supply first. but when it reaches Above synchronous speed. it start generating power.
Correct
@@greatscottlab
if you are going to try it with connected to grid then it will generate power at grid frequency (60 or 50hz)
and if with capacitor bank frequency can be different.
@@greatscottlab I think there may be a way to use capacitor(s) to self-excite induction motors? Not sure if this works without initial power.
@@senorjp21 Robert Murray-Smith has video on this called "An Induction Motor As A Generator Without Altering The Motor"
@@senorjp21 this can be achieved by providing reactive power , usually with the help of a capacitor bank
Scott: "This gear kind of works with the bike chain."
"I secured the gear with 2 zip ties."
Me: *Screams in mechanical engineer*
Beter than hot glue
lmaooo same
I felt that.
"Me: Screams in mechanical engineer" it's always funny when people react this way... but i understand why more often than not stuff just has to work, no be perfect and beautiful.
especially in a test setup
CHINEZU englez that would not work
Bike generator: a device that generates bikes ;)
Fleischwolf- it wolfs Fleisch 🍺🍺🍺
@@nageltermin725 ruclips.net/video/SRCYK5gfLo0/видео.html
In my school I got a question can you explain.
Q-) Electric shock is caused by_____.
. Electric current
. Electrical potential difference
. Electrical resistance
. Electrical energy
(Note you can choose only one option)
Edit:
Correct answer = Electric current
PLS EXPLAIN 🥺.
Edit :
It's electric current because the amount of shock you get depends on the resistance and the supply voltage. It's I = V / R ( Ohm's law. ) Imagine you're connecting your 20 ohm resistor across 20 V. If your supply is current limited ( Constant Current / CC mode, ) the voltage will drop down but if your supply current isn't current limited ( Constant Voltage / CV mode, ) the current will remain high and could burn the resistor. And one more thing, DON'T BELIEVE THOSE " IT'S CURRENT THAT KILLS NOT VOLTAGE " CRAP THEORIES !!!
Here's some videos to make you more understand the laws :
ruclips.net/video/XDf2nhfxVzg/видео.html
ruclips.net/video/DOMs7mYm_zs/видео.html ( skip to 8:29 )
Sorry before. I write these comments on 2 o'clock in the morning, so yeah :-/
good one
So happy you uploaded it anyway
I thought it was interesting enough for a video. So yeah, here you go :-)
you can turn an induction motor into a generator if you kickstart the magnetic field in the rotor by powering the stator at startup for a short time, this will generate residual magnetization which will self-excite the motor under load. i would love to see it in a video, thanks for the video 👍
actually it will require continuous reactive power.
if it is connected with grid or capacitor bank it will take reactive power from it.
otherwise it will not work.
@@rahul-fl2zc yep i forgot about the reactive power source, 3 capacitors will do the job
I can put it on my to do list :-)
Tesla model S already used this for regenerative braking
@@greatscottlab I love this idea too, I need to make a pedal generator from a brushless washing machine motor to charge a battery+ultracapacitor bank pretty soon, ideally without opening up the motor
So it turns out that you only wanted to make a thumbnail with that motor and bicycle tied together. CLEVER
Not really. I experimented a lot with the bike and generator setup but had to decide against it in the video.
@@greatscottlab Yeah we know. Just wanted to tease you lil' bit😉.
@@greatscottlab I think you should reconsider the magnetic assembly design and magnet polarities like I said in my other comment. Match rotor magnet poles with stator poles and also pole area.
Do update us if there is any progress and about the process.
HA HA HA HA HA! Great point!!! I so the thumbnail, my first thought was "Great, A-Synchronous motor as a generator!" ... O_o and then he bought two !!!NEW!!! Induction-motors to prove he is wrong, OMG
PS I'm not an electrical engineer.....
GreatScott! You know you can make some bike chaines smaller ..
I like when creators and engineers like you still upload a video even tho you did not reach your desired amp output. Thank you Greatscott.
Fails happen. At least I learned something and due to the tons of comments I now have plenty of ideas to improve this concept.
LOVED how you dissected all the concepts behind the project!!!!! Best DIY Channel around
Damn you guy who commented that Scott heavily breathes after talking! I can’t un hear this now.
WHAT HAVE YOU DONE TO ME??? WHY????
i hate you...
Noooooooooo!!!!
His name isnt scott
He said that in his lates question video
LMAO true!!
When we are able to admit our mistakes along the way of our progress,we are actually getting closer to the solution. We must not quit at these junctures. Our host in this video shares with us his downfalls and then the ultimate victory.Bravo. Also really like the handwritten detail for the ther side of my brain. Marvelous.Zippy
I think that the main problem you had here is the number of magnetic poles you chose. If the stator has p = 1 (1 pair of poles, or 2 poles) your rotor needs to have also 2 poles. In this case, if you choose 8 magnets, you can put 4 adjacent magnets with the north pole facing outwards, and the other 4 adjacent ones with the south pole facing outwards. Otherwise, for each phase, a EMF will be induced in each coil but they will not have the same phase, so you can get them totally or partially cancelled.
If you go with the 2 pair of poles motor, you can do the same, but creating 2 pair of poles in the rotor also. You can do that with 4 magnets of alternating polarity, or with 8 magnets, but you need to have 4 pairs of adjacent magnets that are facing in the same direction (Just to be clear, if you check the polarity of each 8 magnets, you will have: N N S S N N S S).
I'm impressed. At least for your honesty. Other channels lie on the output of their projects.
You could try using a capacitor bank in order to supply reactive power to the system. Usually the responses get a bit better, but still, not great.
yes, this is NOT the way to turn an induction motor into a generator, a quick google search could show the way
he is replacing rotor with permanent magnets.reactive power will be required if magnetic field has to be created from supply.
so here it is not required.
Sure. I meant he could keep the squirrel cage and just attache capacitors to the stator. I believe it's a simpler solution and possible to provide better results.
adding capacitor bank is a good idea
no needs to modified any part of the induction motor dont tell me to add magnet to the rotor, then you are making the induction motor into synch motor
Thanks so much for taking the time to make this video. I am planning to make renewable energy for free as part of my retirement plan, and your experiments have given me a great insight as to how I should proceed. In scientific endeavour, failure is just important as success, which means you have saved thousands of other humans time and resources by making this video. :)
For a much better operations:
a) the number of pole pairs of the stator should match the number of pole pairs of the rotor
b) the magnets need to be stuck to iron on the inside of the rotor, so that the magnetic circuit has much less reluctance, meaning more magnetic field
c) the air gap should be reduced as much as possible
I think a and b together will already make the generator much more powerful.
As an electronic engineering student currently studying 3 phase AC, I just wanted to say thank you. Your videos really helped me grasp the concept.
You need to reduce the air gap between the rotor and stator. You'll see higher peak voltages after that.
True, but I think it would still not have output a decent amount of power.
He Also need a better rotor he should reuse the original one and he could drill a lot of holes in it to fit magnets
Yeah, that distance between the magnets and the coils looks like a big handicap to the whole thing. The dipole magnetic field is falling off with r^3. Or do you see another reason why energy transfer here was so bad?
@@mdrolc The rotor need to be ferromagnetic to conduct magnetic flux better. Tight airgap and magnet back-iron will reduce reluctance of the magnetic circuit and inprove back EMF.
@@MrThecoco974 👍
@GreatScott, you're brilliant! I kinda love that this video was a series of FAIL, and you went ahead and posted it anyway!!
Thank you for sharing so that your learning experience can become OUR learning experience.
And I will see you next time!!!
I’ve learned that you can use a capacitor to load the coils to generate a magnetic field to generate power and siphon off a bit to keep the field active.
Thanks for drawing and writing. It adds +300 satisfaction points . Idea visualization through drawing is super motivating.
Hi Scott, any Induction motor can work as a generator. It only needs to be fed with reactive power ( via capacitors while running isolated). You may need to modify some winding connections though and no, grid is not required.
im currently working on close to the same project. i just use a hoverboard motor/bldc as the generator. and it works great. Im also glad you uploaded the video anyway. always entertaining content!
Hi, you mentioned using a hoverboard bldc motor. I'd like to do it that way too. What does your setup look like? Do you also use a bicycle? what is your transmission from your drivetrain to your motor? Thanks in advance
You can use it as an induction generator....by applying external low frequency excitation voltage...... don't need to put magnets.....
That is problematic too. How to excite them?
@@sidamarali3030 I think capacitors
Isin't the rotor basically just laminated metal? I don't think there are actual windings. When used as a motor it induces magnetism into the core which makes it spin because of the frequency change, and it lags behind a bit. There are some motor types that do have windings though then yeah you can add an excitation voltage. At least I think that's the case?
It didn't occur to me that an induction motor can't be used as a generator, due to the lack of magnets on the rotor... But I was VERY surprised that it still sucked when you added neodymium magnets to it. I guess it's down to the windings, like you said in the video. You learn something new every day!
More accurate title: Turning Induction Motor to Permanent Magnet Synchronous Generator
pretty much this. the video is a total click bait
your handwritten lettering is very artistic , and is exceptionally good as it syncs with your verbal explanation . Superb presentation.
Put magnets in halbach array configuration so you can generate more power.
That would be quite complicated for greatscott
Why do all the circus, use it as an induction generator.
Best electronics basic channel on youtube. Keep up the content love your videos.
I wonder how well an automotive alternator would work. You can get some pretty high amperage alternators for a reasonable price (new or used).
It would be very difficult for a human to generate power with an alternator, about all a human can sustain for any time is about 100-200 watts, some may peak at about 500 watts for a short tine. But a alternator us in the 2kw range, it could be modified for less power, so you may as well use something more suitable!
See my respose above for M D J
If we take a convenient figure in james's sustainable range of 120 watts at 12 volts we get 10 amps. No magic can increase that. I'll assume that a decent car alternator is at least 80 percent efficient so thé max you can get is about 8 amps, nearly 100 watts. No point in paying for a higher power alternator, buy the most efficient one in spec and match the gearing to human pedalling speed, which can probably be done with standard bike gears. Probably already has. Buying the wrong device and gluing magnets to it to get one watt is daft. So yes, definitely, a decent car alternator unmodified is a good option, just arrange an appropriate gear ratio.
@@raykent3211 Hey Ray, I'm not sure where the 8 and 10 amp figures come from. I have personally seen a 120 amp alternator put out well over 100 amps when under load.
@@jamest.5001 I have used an alternator for a bicycle generator. I had to modify the electronics, but not the mechanics. If you run the field coil at a higher current than designed, you can run it at a correspondingly lower rotational speed. A bit of work with a PWM drive and flyback diode means that the current drawn by the field coil drive is only a fraction of that running through the coil itsself, making the whole thing reasonably energy efficient. You need a little power to start it, but get a lot of power once it's running.
Love that you share your sucessful attempt and your failures.
Whoa! Did somebody say “Generator”? :)
Haha good channel name ;-)
GreatScott! Thanks! :)
Only just noticed how early I am
For sure😂😂😂
@@thomasinwood4377 Dude same 😂
I'm too working on convertion of an induction motor as a generator , but my application is as an flywhee energy storage system . We use the induction machine as a motor first to convert electrical energy to mechanical and then store it as moment of inertia. Then when we require it we use the induction motor as a generator this is usually achived by placing capacitor bank across the motor terminals to feed reactive power as someone mentioned . This will work with no major constructional modification to the machine.
I agree flywheels are cool. But can I know why you want to use it as an energy storage device?
@@karthikeyajavangula8423 I'm currently working a project where we compansate the low voltage ride through in winds mills by pumping the stored energy to the grid . When there is excess wind production the excess is stored in the flywheel and when there is a deficit it's discharged. Conventional storage devices are not that robust and are expensive as a wind mill may face lots of variation in a day.
@@SaiPrasannak So, basically that's like the mechanical version of a capacitor.
By the way, Nice work bro. 😉
Pretty nice work, dude! Thanks for the video! 😃
Question: what about trying with a vehicle alternator? After all, it's used exactly as a generator. 😉
Anyway, stay safe and creative there! 🖖😊
I said the same thing! Lol I hope he sees one of our comments and I'm sure others thought the same. I'd love to see a video like that.
@@erygion Absolutely! I'd love to see it as well! 😃
Car alternators work on a constant speed, its done by a governor... all this put together and you still have to reach the right speed... good option but not an efficient one
Really interesting. I like how you break things down and explain the why's and test newer parts.
Try keeping a poll on your channel, so u get to know what kind of content your viewers like, maybe because of shifting in topics over a long time maybe u lost views. I'm just trying to help you, because u add a lot of effort to your video's and deserve more views.
Great work.👍
the content of your videos SOOO GOOOOOOD
your thicc denglish accent SOOOOO BAAAAAD
i will now watch your videos muted and with subtitles on. thank you very much for the effort to put subtitles in!
keep uploading, you have great videos!!
Looks like the main problem was that your waveforms were not 3 phase, yet you had a 3 phase rectifier
i'm very happy this video was made. I asked about this exact concept in the induction motor video and now i can see this is completely a waste of time. :)
Teacher - How does an induction motor start ??
Student - BRRRRRR...
Why the 3 output sine waves are in phase? I thought they have to be 120 degrees apart to give you maximum phase to phase voltage difference. May be it has to do with the number of magnets on the rotor compared to windings on the stator.
The voltage that occurred in the oscilloscope is not a balanced 3 phase, because they are not 120 electrical degrees apart from each other!!!
You've been watching to many RUclips video's.
Please make longer videos. I love it so much
Around 10 minutes is the maximum I can produce in a week.
@@greatscottlab oh don't take me seriously. I just get this "excitation" to study more about electrical and electronics from your videos that's all
Could a car's alternator work instead?
Yes but the speed matters
Absolutely, but it is NOT an induction motor. The difference is that the rotor in alternator has an electrical winding (coil) on/in it. At a guess it could generate up to 40 Amps at 14.2 volts, which is 568 Watts
@@stevemorse5052 I was meaning to ask if one would work instead of an induction motor, sorry if that wasn't clear.
The device doesn't check to see whether it's being spun by a piston engine, team of horses or a human. Yes it will work and be far better than what's shown here if spun fast enough. Gearing. The video is misleading because he takes some parts from an induction motor and converts it to a different device badly.
I'll always watch your video, doesn't matter if its a fail or success. Keep being awesome!
Why are the sinewaves in phase and not 120 degree phase shifted?
Its not 3 phase motor. It is universal motor
That chain and sprocket combo 👌
Can u make a miniature bldc or induction motor ?
For fun😂😂😂
I will think about it :-)
@@greatscottlab Running the induction motor on a Brushless ESC would be more fun.
Designing is the key
scott， can you make a 3 phase induction motor please like using 3D printer please？
I am not even an engineer or science student to understand but i still love watching because idk i guess i love the videos 😅😂😂
You could connect another motor to the shaft with a split-ring and create an electromagnetic rotor core.
I build a bicycle generator once. I used the alternator from a car engine. The key was to rip out the alternator's built-in voltage regulator circuit and build my own one. Aside from being a bit more energy-efficient, it also let me adjust the output voltage and increased the rotational speed range over which the alternator was able to operate.
Car alternators typically are 'backwards' generators. The field coil is on the rotor, and the power is generated on the stator. The voltage regulator monitors the output voltage and, through a simple feedback mechanism, adjusts the field coil current and thus the magnetic field strength to maintain the target output voltage as the load and rotational speed vary.
My peak generating capacity was fifty watts, but I was only able to sustain that for a brief time. The limitation was biological: I'm just not in very good shape and can't maintain such energetic peddling.
Just 3D Print a sprocket for the Generator to fit the Chain 😆
Damn .........
You put alot of efforts in making these videos
You definitely deserve a 👍🏻💯 ✌🏻❤️❤️
Grog power cave. Grog make fire now
There are cheap motorized bike kits that include a motorcycle chain compatible gearwheel with mounting hardware to secure it to the disc brake side of the wheel . I believe you can find that gearwheel outside of the motorbike kit
"Stay creative and i will see you next time"
Hello! I am a big fan of your projects! I would like to add some things.
An induction motor cannot generate its own voltage and it needs to be connected to the grid and to operate in negative slip in order to produce real power. Even if it is connected to the grid it needs to consume reactive power or else its voltage will collapse.
You basically created a synchronous generator after adding the magnets. In this case the number of poles of the stator needs to be the same with the no of poles of the rotor. Also, maybe you need stronger magnets and smaller gap between the stator and the rotor and most importantly dont forget that the motor was designed for 50hz grid.
Anyway, I love your experiments! Keep going! 🙂
Great video. Your not afraid to go into a motor and change things to see how it works.
I feel your pain man, but solid learning experience. Thanks for the hard work
Hope the next video comes earlier
I can't wait long
Next Sunday :-) Or become a Patreon supporter and watch it now ;-)
The capacitor is providing the energy for the magnetic field. I learned a lot about this from a book using motors as generators. It is the cheapest generator an inductive generator.
Place the magnets on the rotor with two poles, because the magnets you put next to each other neutralize each other. Let it be NNNNSSSS
Another correct answer. I was looking in the comments to see how many caught that error. Well done.
I'm fairly new to this but I concur with many of the comments below.
1.) The distance between rotor and stator is too great.
2.) You are suffering a loss from friction and wobble
3.) Number of magnates, you can maintain the 2, 4, 8 orientation if you want but increase the time in those states by doing 2x8, 4x4, 8x2. For example shorthand 4x4 being 4S->4N->4S->4N
4.) Coverage, in this case a mix of 3.) and the length of the magnets. In your current setup it looks like only about 20% coverage
Anyways, great video loved to see you work, looking forward to checking out your other videos.
A three-phase asynchronous motor basically IS a synchronous generator without any modification, it's the application in the circuit that determines whether you call it a motor and a generator. In some applications it does both, f.e. in modern trains when you want to accelerate the electronics send the three-phase voltage into windings, and when you want to brake a resistance is being applied instead decelerating the train (of course very simplified description)
Hey Scott, I did it once with a single phase induction motor, just using a capacitor. the tank circuit excited the motor than it worked. I used a 1/6 HP motor, and sucefully powered 8 fluorescent lamps powering the motor with a drill.
you are truly honest and creative man))
There is a device in common use called a rotary phase converter which uses a 3-phase induction motor simultaneously as a motor and generator to produce 3-phase power from single=phase power. Capacitors are used to start and run the 3=phase motor on single-phase power. After the motor gets up to speed, the other two phases of the motor generate power. These two phase are then combined with the single-phase input power to yield 3-phase power. This type of device is handy for operating 3-phase machine tools in a home shop where only single phase power is available.
Rotary phase converters are being gradually phased out in favor of solid state variable frequency drives which also can synthesize 3=phase power from single-phase power although the resulting 3-phase power is a PWM waveform. The rotary phase convertor produces true sinusoidal 3-phase power waveform.
you can magnetize the rotor the start by using small amount of DC current through any of the winding for generating a voltage also for utilizing the output you have to place a three phase capacitor bank setup for stabilizing the output voltage, since voltages in induction motor as generator setups tend to collapse when subjected to change in loads. And if you have a constant value capacitor set the IMAG setup can only be used for a constant power output setup..
Dude, you're turning an induction generator into synchronous generator, great job 👍
How about making the shaft of the induction motor spins faster than its rated rpm, and connects its terminal in parallel with a capacitor in order to produce the voltage that you want. That would be great if you make a video this way.
You're amazing 👍
On drill batteries: nice thing about them is you can easily build an adapter that they plug into that gives you USB power or AC out or whatever
You don’t need magnets to excite the magnetic field into an induction motor. Just add capacitors (rated for motor voltage e.g. ~2µF / 350V) in parallel to windings. So this is to deliver reactive power by swapping energy between coils and capacitor in this simple oscillator. If you spin up the motor, voltage will rise quickly due to remanence. But you have to cut off the load with a triac to prevent the field to collapse. If the voltage of self-excitation is high enough, load can cut in... you need a resistor in gate of triac to cut in load at above 50V. Worked great with my 1.5kW wind turbine. Your approach didn't work because the magnetic field induced by the permanent magnets were very weak compared to several amps within squirrel cage at self-induction....
Yeah, you need to feed both rotor and stator in order to work as a generator. They call it DFIG ( Double feed induction generator ) and it's widely used in eolic generation.
Great video as always, greetings from Brazil 👍
some info. at :31, the presence of a Resistive load in the output circuit SCREWS up measurements and reduces the amount if lenz-related drag, in the genny.
@GreatScott!- There's a guy on youtube named Quint Builds who used rainwater as a generator. He has a good design (DIY), does a lot of testing, and may be worth looking at for ideas on a generator. It should work for your bike project as well. Love your content!
Yeah ,he's a pretty awesome guy
Great video! I've always wanted to make a bicycle generator but using a car alternator to charge a car battery. I bet you could make a great system with that.
Up for this comment! 🖖😊
@@MCsCreations Hey you found it :) thank you!
Seeing an angle grinder being used always makes me think of Wintergatans "Pain is Temporary, Glory is Forever"
I am not sure the victim agrees in that case :P
@@enjibkk6850 well, did I ever say that? xD
I made something like this. Changed the three-phase motor into a three - phase generator. It was an old washing machine motor. I did it by rewinding it into a low-rpm 12 pole machine. The rotor, a squirrel-cage type was milled into a 12-side symmetrical polygon, one side for a neodymium magnet. 12 magnets were glued to the rotor with epoxy glue and laminated with glass mat and epoxy resin. The old winding was removed and I rewound this motor with an enameled copper wire with diameter of 1 mm. At ca 60 rpm it gives me about 8 V after the three-phase full bridge rectifier. It is easy to connect the buck regulator set to 5 V and charge the smartphone. This was absolutely not cheap and quick work, especially, that I had to rewind it twice (man learns by trial and error...). Phase voltage at 500 rpm is some 30 V RMS (it gives about 70 V after rectifier), frequency is 50 Hz.
First, you should check how many poles has your stator winding and apply exactly the same number of magnets on the rotor. It is easy from reading a parameters plate on the motor: about 2850 rpm is 2-pole, 1450 rpm is 4 pole, etc. If you just put some arbitrary number of magnets on the rotor, without checking the type of winding - you will just loose time and work.
Moreover, it you want low-rpm generator, you must rewind it with thicker wire, or you will get just a device to change mechanical energy into heat...
The less rpm machine - the more iron, copper and magnets it needs for the same power as high - rpm machine. Roughly inversely proportional to RPM - 2 times lower RPM means 2 times as much copper, iron and magnets for the same power.
That's why generators in big windmills have a gearbox increasing the RPM from ca 60 (propeller) to like 3000 (generator rotor), because low - rpm, directly propelled generator would be insanely HUGE at powers of the order MW...
The way it was described in the lectures that I attended is pretty much what the previous comment tells. With a formal clarification or two. You can use the asynchronous motor as a generator, when you have AC magnetizing, not DC that the permanent magnets represent. The terminology actually is that with BEYOND SYNCHRONOUS SPEED any asynchronous 3-phase motor will feed REAL power to the network, while consuming REACTIVE power from the network. The reactive power is what provides the alternating magnetic field. Another practical issue is that the motor is very critical to what is called air gap between the rotor and the stator. Consider that good soft magnetic iron conducts magnetic flux some 3 or more orders of magnitude (more than a thousand-fold) better than air. A 1 millimeter air gap resists the magnetic flux more than a 1000 millimeter path via the iron.
I recall how a small stream was not a good proposition for a standard synchronous generator due to all critical controls required. So an asynchronous generator was installed and happily produced 200 kW power to the network. There was no need to synchronize the rotation speed to the existing power line frequency and phase. You just started the generator as a motor and then added more speed from the turbine to exceed the line frequency. The generator ran faster, if there was more water and supplied more power to the network. All that happened automatically, no speed controller needed.
"Creating electrical power on your own is a pretty marvelous feeling"
- Emperor Palpatine
Moral from great scoutt:Failure is the first step to 👍👌
The induction motor has to achieve super-synchronous speed to start generating electricity. That's then is called an induction generator which is used for power generation through wind energy.
@GreatScott! I think, you were wrong, when you placed the magnets in alternate order. You shuld place them to get the rotor with one side fully south, and the other fully north; becaus when you run the induction motor, that is the induced magnetic pattern in the rotor, not 8 south, and 8 north. If i were you, i would give a try to that setup... Correct me, if I am wrong
Depends on how many poles the winding has.
@@matthewmaxwell-burton4549 He stated the first motor is 2 pole and the 2nd motor is 4 pole. Reading the comments, you beat me to the answer. I posted that too, but wanted to see how many people here actually caught that error.
Use a cheap 120v DC treadmill motor like me. 100 watts is easy to generate, though, my output voltage is only around 45v. Still excellence for a power diode to a huge cap and a switching DC-down converter regulator from TI which will take in 75vdc through ~9vdc and output a select-able 12 through 24 vdc up to 10 amps.
Though, to get the RPM up, I had to use my rear tire's diameter as a pulley to motor tiny pulley.
Also, the flywheel on most treadmill motors was needed to smooth out the load and pedaling torque.
Also, at least the treadmill motor I chose has no cogging!
Just use capacitors to self-excite and use electronics to make a stable voltage. You made me cry with what you did to that rotor!
That's the best solution....the only drawback is that he would have to peddle faster than the motors rated RPM to start generating electricity. Which is hard to do because once you past the slip speed resistence sets in even without a load
@@rogerrabbit7469 Probably be better than this sorry state of a rotor even at low rpm.
Recommendation .U can use24 v dc RO pump usually used in water purifiers these are usually consumes 1.5 amps at 24v dc and can act as a better generator..
Induction motor can work as induction generator when slip is negative,that can be done by either moving motor shaft faster than rated rmp or by decreasing supply frequency.it can only provide active power not reactive power, reactive power has to supplied from source.
thank you sir the information, i like your experiment, i love to do that but i have no time. but you did already, puting magnet to the rotor need only low rpm and created ac voltage . good job sir.
We used to have bike generators back in the 80's. It was a small device that picked up on the side of the rear wheel and made enough power to light the front and rear lights. Not very bright though from what i remember.
I like the video because it is helpful and knowledgeable. What I can suggest is that you can use DC motor which is quite efficient and reliable. Tnx😄
You can use a regular 3phasr induction motor as a basic generator by flashing a phase across a battery to magnetise the iron then spinning it with 3 motor run capacitors across the phase wires.
You missed the whole Asynchronous Generator. You somewhat match the inductive reactance of the SCIM to a 3 phase connected capacitor bank reactance to create a near tank circuit and the motor will generate nearly the same power as it is rated to put out. Don't mess with the rotor.
So if he added capacitors to the unchanged motor it wouldve generated almost the same ammout of power its rated to put out?
@@sebagomez4647 You are understanding what I wrote. I have actually done it in my lab to show my students and fellow instructors.
@@ReevansElectro how nice. I have one of those motors so im going to try to see how much i can generate
Or just take an alternator from a car and hook it up via a belt and easily generate stabilised 14.4ish Vdc and as many wqts your stamjna can handle.
The second issue with asynchronous motar are that the voltage fluctuating quite a lot base of the load, synchronous motor are better choice but they're a hassle to work with because of the DC requirements IF I remember correctly.
And as always, your videos are both entertaining and educational.
//Cheers.
Even tho it did not work well. Still liked this video. As you learn more from fails. If we watch it, then hopefully. We wont make the same mistakes.
Nice work, Scott, i think that the problem is not the orientation of the magnets, or even the magnets, you can use just two of them (pretty big, obviously). Remember that the separation of the poles (on the stator) is made for generate a rotating magnetic field , the rotor will just act as a big magnet, if you want to generate power, with an inducton motor, i suggest, changing your rotor for an alternators car rotor.
Induction motor can generate electricity only if the slip of the machine becomes negative, that is if the shaft speed becomes greater the synchronous speed. But the machine needs reactive power to do this, which can be supplied from the grid or by connecting a delta connect capacitor bank at its three phase output.
You need a permanent magnet alternator or generator for that project. Bicycle lighting sets have used those for about a century, usually driving them from a roller against the bicycle tire.
The rotor might work better with magnets mounted in a helical configuration.
There on internet is couple videos of people using 2 or 3 capacitors to convert 3 phase motor to one phase AC generator without any motor modification (google result of "AC 3 phase motor generator with capacitors"). To start generating it needs slightly more RPM than normally that engine runs. With that caps 3phase motor can run on one phase (with reduced start torque).
Hi there pal just watched your video on making the hand crank generator, which what I watched was absolutely amazing, from start to finish you should have your own business pal, thanks
To go from three phase ac to DC would require a decent full bridge rectifier and subsequent voltage and amperage regulation. 5v 500mA for standard USB charging. 5v 2A for tablet charging.
This video is really interesting. When an Induction motor runs as generator, it's called Asynchronous Generator and it happens when rotor speed is faster than synchronizing speed of the field, i.e. the slip is negative. I suspect if we normally run an induction motor from supply and than rotate the rotor even faster by providing more power to the shaft, our motor should generate and feed back to the supply. I'm interested to see if you can do such experiment and post a video on it. Induction motors are used in electric car and act like generator during braking resulting the braking power to be stored on cell (aka Regenerative Braking).
If you want it as a good generator with the niyodium magnets you have to change the winding obviously. You have wind it accordingly to a BLDC motor. So it will be a big BLDC motor and will generate a lot of energy.