Our pal Greg from DIY live sent in this article he wrote trying to differentiate the difference between AC and DC motors and generators – “I ran across some cool pages while studying about AC vs. DC motors. I was interested in taking a small DC motor, and connecting a propeller to it. I want to stick the motor on the outside of my car, and generate a small DC voltage to power my toy, ie. an iPod, or my cell phone. I need 5v for the task. The question I have been having is if you take a DC motor, and spin it, will you be producing a DC voltage, or an AC voltage. The answer it seems is that you will produce a DC voltage. It is kind of complicated, but is very interesting. The key to understanding a DC motor vs. an AC motor is to see how they are wired. A DC motor has a commutator.”Link.

Related:

• HOW TO – Simple DC Motor Controller – Link.

10 thoughts on “DC/AC motors and generators”

1. sam lamewolf says:

can you make a 36 volt dc motor into a 110 or 220 ac gen.

1. You would need a DC to AC converter
——–
look would I found. i wonder if this would work. ugh… I know noting about this stuff….

would this work?
I found a DC magnetic motor. Will this work? It looks like a motor used in electric cars or vehicles. The power rating caught my eye. Could it be that simple? I’m not worried about the RPM, I have that problem solved so I can get any RPM needed without wind power. Could this motor put out as it states 11.5 KW continuous? If so, Why would I buy a 10kw windmill or solar system for \$30,000.00 USD when I can use a permanent magnet DC motor like this for 600.00 capable of 11.5 KW continuous. The equations V(V) × I(A) = P(W). Is this motor really going to put out 11KW of electricity or am I missing something here? Geez, I’d be ecstatic if it would even do 5KW. Sorry for the stupid question. I’m sure you are probably laughing at my craziness.

Power: 11.5 kW cont– 23 kW pk <—– ?
Voltage: 12-72 Volt rated
Max Speed: 3700 rpm @ 72V unloaded
———————————
EMC-RT200 w/
Alltrax AXE7245 Controller
38HP pk. Electric Drive Kit

Includes

EMC-RT200 Motor
Alltrax AXE7245 Controller
Choice of Throttle
Contactor
Wire Kit
Fuse Holder w/ Fuse

EMC-RT200 Motor

The EMC-RT200 is a brush-type, permanent magnet DC motor with very high efficiency. Capable of 11.5 KW continuous and 23 KW for 1 minute. For voltages from 12 to 72 VDC input and 200 amps continuous (400 amps for 1 minute). Designed for battery operated equipment. For more information, see the Performance Information section. Motor weight of 39 pounds. This motor has similar performance to the Lynch, Lemco, and AGNI motors

Power: 11.5 kW cont– 23 kW pk
Voltage: 12-72 Volt rated
Max Speed: 3700 rpm @ 72V unloaded
Size: 8" OD, 7.4 " long (w/o shaft)
Shaft: 7/8"x 1-3/4", 3/16" key
Weight: 39 lbs.

Click on an image above to enlarge in a new window ^
Controller

Alltrax AXE7245 72V 450A Programmable Controller

Alltrax controllers are fully programmable speed controllers for permanent magnet and series motors. The free Windows compatible programming software allows for complete control of max current, max speed, hi and lo voltage cut off, acceleration and deceleration rates and custom throttle settings.

Programmable via RS232 comm port using PC or Laptop
Integrated anodized heat-sink with multi bolt pattern for flexibility
Fully encapsulated epoxy fill – environmentally rugged design
Advanced MOSFET power transistor design for excellent efficiency and power transfer
1/2 Speed reverse option and "Plug Brake" options available

450 Amps
24-72 Volts
Works with 0-1k, 0-5k, k5-0 ohms, 6-10.5V & ITS Throttles

Throttle

Choose from…
– Magura Twist-Grip Potentiometer Throttle
– EZ-GO Pot Box Throttle (PB-6 Drop-in Replacement)

Contactor

Please specify your contactor coil voltage at checkout. 24V, 36/48V, or 72V

2. would this work?
I found a DC magnetic motor. Will this work? It looks like a motor used in electric cars or vehicles. The power rating caught my eye. Could it be that simple? I’m not worried about the RPM, I have that problem solved so I can get any RPM needed without wind power. Could this motor put out as it states 11.5 KW continuous? If so, Why would I buy a 10kw windmill or solar system for \$30,000.00 USD when I can use a permanent magnet DC motor like this for 600.00 capable of 11.5 KW continuous. The equations V(V) × I(A) = P(W). Is this motor really going to put out 11KW of electricity or am I missing something here? Geez, I’d be ecstatic if it would even do 5KW. Sorry for the stupid question. I’m sure you are probably laughing at my craziness.

Power: 11.5 kW cont– 23 kW pk <—– ?
Voltage: 12-72 Volt rated
Max Speed: 3700 rpm @ 72V unloaded
———————————
EMC-RT200 w/
Alltrax AXE7245 Controller
38HP pk. Electric Drive Kit

Includes

EMC-RT200 Motor
Alltrax AXE7245 Controller
Choice of Throttle
Contactor
Wire Kit
Fuse Holder w/ Fuse

EMC-RT200 Motor

The EMC-RT200 is a brush-type, permanent magnet DC motor with very high efficiency. Capable of 11.5 KW continuous and 23 KW for 1 minute. For voltages from 12 to 72 VDC input and 200 amps continuous (400 amps for 1 minute). Designed for battery operated equipment. For more information, see the Performance Information section. Motor weight of 39 pounds. This motor has similar performance to the Lynch, Lemco, and AGNI motors

Power: 11.5 kW cont– 23 kW pk
Voltage: 12-72 Volt rated
Max Speed: 3700 rpm @ 72V unloaded
Size: 8" OD, 7.4 " long (w/o shaft)
Shaft: 7/8"x 1-3/4", 3/16" key
Weight: 39 lbs.

Click on an image above to enlarge in a new window ^
Controller

Alltrax AXE7245 72V 450A Programmable Controller

Alltrax controllers are fully programmable speed controllers for permanent magnet and series motors. The free Windows compatible programming software allows for complete control of max current, max speed, hi and lo voltage cut off, acceleration and deceleration rates and custom throttle settings.

Programmable via RS232 comm port using PC or Laptop
Integrated anodized heat-sink with multi bolt pattern for flexibility
Fully encapsulated epoxy fill – environmentally rugged design
Advanced MOSFET power transistor design for excellent efficiency and power transfer
1/2 Speed reverse option and "Plug Brake" options available

450 Amps
24-72 Volts
Works with 0-1k, 0-5k, k5-0 ohms, 6-10.5V & ITS Throttles

Throttle

Choose from…
– Magura Twist-Grip Potentiometer Throttle
– EZ-GO Pot Box Throttle (PB-6 Drop-in Replacement)

Contactor

Please specify your contactor coil voltage at checkout. 24V, 36/48V, or 72V