Can you use a single phase motor to create three phase power.

[DPG]

Yes, in proportion.

For an ideal generalised generator or motor:
Torque is proportional to current
Speed is proportional to voltage
Mechanical power is equal to electrical power.

Run your car engine at idle and then switch on the rear demist and headlights together, and you will hear the engine note dip slightly, at least for a second while the ECU adjusts the idle valve to compensate. That is the effect of adding about 300 watts of load on the electrical side, absorbing 1/2 horsepower of extra mechanical power from the engine. (Car alternators are rather inefficient.)

It's hardly funfair season now, but go to a fairground, stand by the generator powering a large ride and hear and feel the engine come under load as the ride pulls away. As a generator man and vintage engine enthusiast I have to say there is nothing like the feel of a big old diesel opening its fuel rack to meet the demand. On a showmans steam road loco belted up and driving a ride with a high motor load like an ark, you can often see the governor move in response to every stud of the rheostat.

/dreamy

Oohh - rheostats, governors. Thank flip he didn't say knife switches or I may have got over excited. On slate panels. Mmmmm. Nice!

 

[StephenRowley]

BUT it is impossible to get more out than you put in. Several Nobel Prize winning physicists proved this hundreds of years ago

If there was possible to break this fundamental law the universe would just be one giant infinity hot fire ball.

 

[Lucien Nunes]

@DPG

Watt flyball guv'nors on Corliss-valve triples,
Dynamos whirring with tuneful slot ripples,
Carbon pile rheostats tensioned with springs;
These are a few of my favourite things...

 

[Edtwozeronine]

One of my lecturers did an experiment (not in the time I was at the college several years before) and they got a form of 3 phase out of a cars alternator. He did try and explain it to us students but I feel we all got rather lost...

 

[StephenRowley]

One of my lecturers did an experiment (not in the time I was at the college several years before) and they got a form of 3 phase out of a cars alternator. He did try and explain it to us students but I feel we all got rather lost...

Car alternator are three phase generators with a full bridge rectification.

So you just connect before the diodes.

 

[johntheo]

Yes, in proportion.

For an ideal generalised generator or motor:
Torque is proportional to current
Speed is proportional to voltage
Mechanical power is equal to electrical power.

Run your car engine at idle and then switch on the rear demist and headlights together, and you will hear the engine note dip slightly, at least for a second while the ECU adjusts the idle valve to compensate. That is the effect of adding about 300 watts of load on the electrical side, absorbing 1/2 horsepower of extra mechanical power from the engine. (Car alternators are rather inefficient.)

It's hardly funfair season now, but go to a fairground, stand by the generator powering a large ride and hear and feel the engine come under load as the ride pulls away. As a generator man and vintage engine enthusiast I have to say there is nothing like the feel of a big old diesel opening its fuel rack to meet the demand. On a showmans steam road loco belted up and driving a ride with a high motor load like an ark, you can often see the governor move in response to every stud of the rheostat.

/dreamy

Or listening to the steam engine slowing down a little when under load from the men throwing the sheaves of corn (after first cutting the binder twine) into the threshing machine drum and then watching the engine man adjusting the speeder spring on the flyball governor to restore the speed , my first introduction to proportional (droop) governing, happy days, many moons ago.