120v AC producing bike hub generator?

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ac would allow me to run this directly
https://www.kitchenwareonline.com/320-watt-microwave-and-12-volt-inverter-package-kit24-c2x27010742











i see youtube could have all my answers but i dont see the simplest version of producing ac and instead see alternator motors making DC and an inverter. And inefficient with the friction drive. where's an ac generating bike generator? or using a common ac motor from something? like the washing machine.

brushless motors in washing machines. https://youtu.be/fUJcB0cvy1k i thought it would be ac.
 
To run a 320W appliance on an inverter, you should expect to put in at least twice that much mechanical power before efficiency losses. How are you going to do it?
 
Chalo said:
To run a 320W appliance on an inverter, you should expect to put in at least twice that much mechanical power before efficiency losses. How are you going to do it?
thats why i want to make 120 AC directly and skip the losses of an inverter. im thinking maybe use some ac motor that runs at a speed similar to cycling cadence or probably could be more efficient with a designed motor.

giant screen tv's barely take any power. i could cook and watch tv all day...a small or medium sized screen is good enough and sprints for meals.
https://letsavelectricity.com/how-much-power-does-a-tv-use-in-an-hour/#:~:text=Most%20TV%20available%20in%20the%20market%20has%20wattage,Know%20Your%20Television%20Wattage%3A%20Courtesy%20%E2%80%93%20Google%20Images
 
Hummina Shadeeba said:
Chalo said:
To run a 320W appliance on an inverter, you should expect to put in at least twice that much mechanical power before efficiency losses. How are you going to do it?
thats why i want to make 120 AC directly and skip the losses of an inverter. im thinking maybe use some ac motor that runs at a speed similar to cycling cadence or probably could be more efficient with a designed motor.

giant screen tv's barely take any power. i could cook and watch tv all day...a small or medium sized screen is good enough and sprints for meals.
https://letsavelectricity.com/how-much-power-does-a-tv-use-in-an-hour/#:~:text=Most%20TV%20available%20in%20the%20market%20has%20wattage,Know%20Your%20Television%20Wattage%3A%20Courtesy%20%E2%80%93%20Google%20Images

A pedal alternator will vary its AC frequency, voltage, and deliverable current according to fluctuations in pedal RPM and load. There aren't very many AC electrical devices that will work correctly (or at all) when coupled to wild AC, even if the average voltage is more or less okay. AC/DC motors and resistance heat devices will work... but even these things will fluctuate in output or speed along with the variations in pedal input.

A surprising number of household items will run on steady DC, though. Many electronics use internal rectifiers and voltage regulators to turn mains AC into a lower DC voltage. If the conversion is done electronically rather than with a transformer, they'll often accept DC without issue. Some can probably take variable AC, but this is risky. Pedal too slow and they'll shut down, too fast and you'll pop the capacitors or transistors inside.

When I made a stationary cycle generator, I used a lead-acid battery to buffer the load and to provide a working voltage that set the operating speed for the pedal dynamo. When dynamo voltage exceeded battery voltage plus the power diode's forward voltage, current began to follow and apply a load at the pedals. When pedal power was inadequate, the battery supported the load, and when pedal power exceeded the load, it charged the battery.

You could use a brushless motor/alternator with a bridge rectifier to do the same thing. The energy reservoir doesn't have to be 12V or an SLA battery, but whatever voltage you use must correspond to what your alternator can deliver at normal pedal RPM, and the battery must be able to charge without damage at the implied rate.
 
You're not gonna find it. Better to convert your battery voltage to AC.

Not that i know of any inverters worth a crap for that purpose. I've bought many, and they either blew up upon connection or had such poor quality power it wasn't even useful :/
 
Need to regen power into a battery and use a dc-ac converter to run stuff on 120v(ac).
dd motor hooked up to a bicycle and you can pedal.

Or, look for a 12V microwave
https://12voltsplus.com/pages/12-volt-microwave

See what truckers use
12V 12A https://cdl101.com/best-microwave-truckers/
RoadPro Portable Stove

Then perhaps you can design some circruitry to hook up to the regen controller to run 12V.
 
Chalo said:
A pedal alternator will vary its AC frequency, voltage, and deliverable current according to fluctuations in pedal RPM and load.



If I add a flywheel maybe I could produce some consistent ac that won’t fluctuate? Im only interested in producing ac from the bike and going directly to something like a tv or maybe the 350w microwave. If I could watch tv and put out like 200 watts the whole time that would be fantastic

Please give me advice on doing that. The generator Id like to make. and just make it with a very heavy rotor. But using magnets and coils and a machined steel rotor and ...some kind of stator. Maybe the washing machine stator. what you think would be a good design?
 
nicobie said:
I think Markz has a viable solution. Use your energy to charge a 12V battery to then run 12V appliances.

Sounds good but don’t see a 12v tv, and going directly from pedal power to the tv I could potentially be most efficient. Splitting hairs there maybe but going direct from motor to tv is cool in its simplicity. It should be possible. Surely a big flywheel hub generator could produce consistent output.


markz said:
Need to regen power into a battery and use a dc-ac converter to run stuff on 120v(ac).
dd motor hooked up to a bicycle and you can pedal.
.
Sounds nice in using the hub motor and esc but ultimately its too complicated for me and less efficient.
 
You cant get 120Vac straight out of a motor without some kind of circuitry to convert dc to ac.
Its bee 100 yrs since I did BASIC motor theory in school but my guess is: You'd need to step the square wave into lots of small steps, then convert to above zero and below zero, then smooth out the millions of steps. But then even before all that happens you need to get rid of the high fluctuations done by the pedaling, as been mentioned. To much of a headache.

AC motors are a total different ball game then DC motors. And thats input of AC into the motor from a DC battery. Again, its been 100 yrs since school but theres more inductive loads, this that and the other. Like 3 phase and 6 phase power and getting 420V for industrial machines then 240V dryer outlet. Remember it all costs money, and it costs time. How much is your time worth and how rich are you?

Hummina Shadeeba said:
Chalo said:
A pedal alternator will vary its AC frequency, voltage, and deliverable current according to fluctuations in pedal RPM and load.



If I add a flywheel maybe I could produce some consistent ac that won’t fluctuate? Im only interested in producing ac from the bike and going directly to something like a tv or maybe the 350w microwave. If I could watch tv and put out like 200 watts the whole time that would be fantastic

Please give me advice on doing that. The generator Id like to make. and just make it with a very heavy rotor. But using magnets and coils and a machined steel rotor and ...some kind of stator. Maybe the washing machine stator. what you think would be a good design?
 
Theres 12Vdc everythinng and anything. Fridges are 12V, TV's are 12V, there is a whole industry devoted to 12V from camper vans, to solar. Google is your friend!

Whats to complicated is you wanting 120Vac from a motor to a converter. The easiest way to do things, the cheapest way to do things, the fastest way to do things is as been mentioned.

Or if you trully want to cheap out and get power. If you have access to very cheap if not free wood.
Google Gasifier, but tthat might hurt your "green" thumb.


Hummina Shadeeba said:
Sounds good but don’t see a 12v tv, and going directly from pedal power to the tv I could potentially be most efficient. Splitting hairs there maybe but going direct from motor to tv is cool in its simplicity. It should be possible. Surely a big flywheel hub generator could produce consistent output. You wont get any efficiency gains trying to get 120Vac out of the mystery device hooked up to your motor to convert.


markz said:
Need to regen power into a battery and use a dc-ac converter to run stuff on 120v(ac).
dd motor hooked up to a bicycle and you can pedal.
.
Sounds nice in using the hub motor and esc but ultimately its too complicated for me and less efficient.
 
markz said:
You cant get 120Vac straight out of a motor without some kind of circuitry to convert dc to ac.

When you turn a BLDC motor like those almost all of us use, it puts out three phase AC (with variable frequency and voltage).
 
Hummina Shadeeba said:
Sounds good but don’t see a 12v tv,
Every large (32" and up) monitor (some of which are TVs, all of which have HDMI inputs and some have tuners) I have here run off DC voltage, some 12V, some 19V. They have a big power supply as an external box that connects to the AC from the wall to create that DC. ;)

I'm sure there are some (perhaps many?) around that directly connect to the wall for AC, and perhaps that's what you have there.
 
12V televisions - https://www.12volt-travel.com/12-volt-televisions-c-684.html and 22" led uses 6W of power :shock:
from https://www.12volt-travel.com/
12V ----- Vacuums, dvd players, blankets, heated mugs, coffee makers, coolers, hot plates, crock pots, fridges, freezers.
 
Chalo said:
markz said:
You cant get 120Vac straight out of a motor without some kind of circuitry to convert dc to ac.

When you turn a BLDC motor like those almost all of us use, it puts out three phase AC (with variable frequency and voltage).

id make a two phase ac generator. https://www.youtube.com/watch?v=H_xFgn6UTOs


this huge 40" screen supposedly only uses 70 watts! thanks for the links. i can produce 70 watts forever on my bike. https://www.12volt-travel.com/large-screen-40inch-12-volt-led-dc-tv-p-23649.html

i thought it would be more efficient and require less sweat from me if i produced ac thinking tv's ran on ac...or do they and even though my tv doesnt have one of those rectifying power supplies it connects to the wall with, maybe its got it internally and doing the conversion there? Maybe ac is always rectified to dc for tvs? but at only 70 watts needed worrying about conversion losses isnt worth it. and i guess i need to add the other bits to smooth the current and voltage or is a battery in parallel good enough?
 
Hummina Shadeeba said:
Maybe ac is always rectified to dc for tvs? but at only 70 watts needed worrying about conversion losses isnt worth it. and i guess i need to add the other bits to smooth the current and voltage or is a battery in parallel good enough?

Most electronics these days run on DC power, rectified from AC and then converted to lower voltage by a switching power supply.

If you put a battery in parallel with your generator, it will smooth the power, take over during interruptions, and absorb excess voltage from the generator. In most cases, you won't need other filtering or smoothing.

Do keep an easy to read voltmeter on your battery, so you'll know if it's getting out of range. I would use a lighted one, and put it on the load side of the switch.
 
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