Can Capacitors Create Specific Phase Shifts in DIY Three-Phase AC Systems?

In summary: The most important question I have regarding the three phase power is that I know you can use 3 individual single phase ac lines and use a capacitor to make two of the three legs 90 degrees apart. Is there a way to use capacitors to make the second leg 120 degrees out of phase from the first leg and the third leg 240 degrees out of phase from the first leg?You can use capacitors to make the second leg 120 degrees out of phase from the first leg and the third leg 240 degrees out of phase from the first leg.
  • #1
StephenD420
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0
Hello everyone

I am trying to make a small three phase ac stator so a rotating magnetic field will be produced. I can use a ring with an outer diameter of 3 inches and an inner diameter of 1.5 inches with each of the six poles being 1 inch with about 100 turns of 24 magnet wire or a ring with an outer diameter of 8 inches and an inner diameter of 6 inches with each of the six poles being 2 inches with about 200 turns of 24 magnet wire. Since I live in the US we only have single phase ac, not three phase. I bought a variable frequency drive that produces three phase ac from single phase ac but it is only 4 amps and since I would like to make my magnetic field about .5 to 1 Tesla I do not know if that will be enough? Is it enough? Will this be enough turns to get the .5 to 1 Tesla?

The most important question I have regarding the three phase power is that I know you can use 3 individual single phase ac lines and use a capacitor to make two of the three legs 90 degrees apart. Is there a way to use capacitors to make the second leg 120 degrees out of phase from the first leg and the third leg 240 degrees out of phase from the first leg?

Thank you so much for your help.
Stephen
 
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  • #2
oh the small ring is about 1/8 inch in depth with 1/8 inch depth coil forms(iron or steel) and the larger ring is about 1/8 inch in depth with 1/2 inch depth coil forms(iron or steel)

Thanks
Stephen
 
  • #3
StephenD420 said:
The most important question I have regarding the three phase power is that I know you can use 3 individual single phase ac lines and use a capacitor to make two of the three legs 90 degrees apart. Is there a way to use capacitors to make the second leg 120 degrees out of phase from the first leg and the third leg 240 degrees out of phase from the first leg?

Thank you so much for your help.
Stephen

No, you cannot make 3 phase power using 3 individual single phase ac lines and capacitors.
 
  • #4
It was common to use a 'shaded pole' in order to get an induction motor to work by turning a single phase supply into two phases. All old tape recorders and record players used this cheap arrangement.

Using the right combination of R, L and C and a transformer (to get a phase reversal), you can produce any phase shift you want but it can involve dissipating a lot of power in your resistor (likewise, a shaded pole motor runs hot, although it only delivers very low mechanical power).
 
  • #5
How about just using two ac lines with one haivng a capacitor in series? Would that create a rotating magnetic field or would it be pulsing, as I want it to rotate counterclockwise in space around the inside of the stator ring?

Also, how do you layer coil turns for a coil? Do you just start at the top of the coil form and then coil over the top of the previous coil in the same direction and then just twist the two endings together for the leads at the top and bottom of the coil?

Thanks.
Stephen
 

FAQ: Can Capacitors Create Specific Phase Shifts in DIY Three-Phase AC Systems?

What is three phase AC?

Three phase AC, or alternating current, is a type of electrical power transmission where three separate, equally spaced waves of electricity are used instead of one. This allows for more efficient power delivery and is commonly used in large industrial and commercial settings.

How does three phase AC differ from single phase AC?

The main difference between three phase and single phase AC is the number of waves used. Single phase AC uses only one wave, while three phase AC uses three. This allows for a more balanced distribution of power and can handle larger loads. Single phase AC is typically used in residential settings.

What are the advantages of three phase AC?

Three phase AC has several advantages over single phase AC. It provides a more efficient and balanced distribution of power, which reduces the strain on individual power lines and equipment. It also allows for higher power output and can handle larger loads, making it ideal for industrial and commercial use.

How is three phase AC generated?

Three phase AC is generated using three separate power sources, each with their own set of coils and magnets. These power sources are arranged in a specific way to create three equally spaced waves of electricity. The resulting power is then transmitted through a system of power lines and equipment.

Can three phase AC be converted to single phase AC?

Yes, three phase AC can be converted to single phase AC using a device called a phase converter. This device takes the three waves of electricity and combines them into one, which can then be used in single phase applications. However, this conversion may result in a loss of power and efficiency.

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