Why 3 Phase Power? Why not 6 or 12? 

That was what I was thinking as I was watching the video. How much more expensive and complex it would be to double everything. Miles and miles of extra wire, plus all of the breakers, transformers etc. Three phase is already very expensive. Six phase would practically take an act of Congress to get it anywhere. Only heavy industry could ever afford it.

@@bekimbal9658 In some places, particularly California, the cost isn't putting stuff in. The cost is the environmental, zoning, not-in-my backyard lawsuits it takes to put anything in. In many places, you have the cost of buying the right-of-way and maintaining it. These remain constant regardless of how many wires you put in. Then you have the cost of the energy lost due to inefficiency. That's why technologies like HVDC and superconducting transmission lines are being deployed. The moral of the story is considering costs isn't about installation or capital costs, it's lifecycle costs.

@@straightpipediesel Wow! Thanks for the info. I am glad I don't live in California. If I had a lot of capital and wanted to locate a business, I don't think California would ever make the list.

What can be done economically, legally, ethically, environmentally friendly. Unfortunately we have some people (Republicans) who care only about the economics and the rest be damned.

@@mattfoley6082 three phase vs six phase has nothing to do with politics. And most engineering projects often get tripped up by costs. Just not in the way you think.

snap.....

HektorbajsmanIII it's 5 am for me

2.11am here. ;-)

9PM for me. Well I work overnights and got to be at work in couple hours. Usually I am sleeping right now until 10 35PM before I gotta be at work.

no control? don't let it phase you ;) HAH * bad joke ik, I'll go uninstall youtube

Damn that’s funny

😂😂😂

So funny

@Hungarian OK. We're friends now. Now what??

This had me wheezing

this is why we must ensure knowledge is never lost, share it!

or squirrel 2:48

....or the crazy guy wasting hours of my employees time talking about breeding betta fish when I worked at petsmart.

I like the conservation of his emotional energy. Say what's most important, without any fluff or ego.

What is he saying that is nonsense? Stfu

Tesla > Edison

Marcus Tornea Do your snide remarks apply to other fields? Can Ford detail the benefits of torsen differentials? Or turbo power?

Was Ford activelly trying to destroy people who came with better inventions? No he didn't. Edison on the other hand was a complete cunt against AC.

yeah take a day off ferrous bueller!

Just as ironic is that TESLA, the car, runs on DC Power.

he is awful at explaining.

the function of college is NOT to educate, its function is to INDOCTRINATE !!!!

This guy would put you into a coma.

A prominent example in recent times is 6 phase ev motors. Both Ford in their race-only SuperVan and Koenigsegg in their commercial Gemera used six phase motors to a scary effect

...or so the Romulans would have us believe.

We've got something going here. You repliers are a very large cut above the typical YT reply legions.

🧐🧐🧐❤️❤️❤️🇬🇧🇬🇧🇬🇧😂😂😂😂👍🏻👍🏻👍🏻🤝🤝🤝💪🏻💪🏻💪🏻🤣🤣🤣

As long as we stay near neptune. There have been reported sightings of a high number of Klingons around Uranus. ;-)

Trev0r98 Romulans love David Hasselhoff.

*bark* OHMYGOCAN'TYOUSEEIT'SASQUIRREL? *bark bark* YOUREALLYDON'TUNDERSTANDTHEWEIGHTOFTHISSITUATION! *bark bark bark* ASQUIRREL!!! *barkbarkbarkbarkbark*

when the guy is too boring and you se a squirrel

2:49. Thanks.

haha! good observation.

i would say lizard

Answer: /watch?v=MnH_ifcRJq4

"Taking the time"? Yeah, he sure did that!

LMFAO 😁

john woodworth lol

Another winning reply. You guys out there must be practical, practicing, shrinks.

@Ryan Plethra As often, your reply to John W. went to me, John L. Sorry. (But I do appreciate the different takes on divorce. My take was a release of 20-years worth of tension headaches, tho I didn't realize it until the gavel was banged.) Cheers, JL

Actually no, it's most cost effective today with no phases--DC. Why China's transmission grid is being built as DC. His idea might have been useful if the electronics used to convert to and from DC hadn't been dramatically improved.

@@straightpipediesel Note the keyword "more" cost effective. And AC is generally still cheaper over shorter distances.

i haven't understood from the video, so that means if taking aside complexity and economic problems, 6/12 phase would be better than 3 phase, right? or it doesn't provide any benefit?

Naturally there are competing factors. It would have been more interesting if he started with just one phase, and explained why two or three were better. I imagine it's a combination of generators working better with multiple phases, wiring being more efficient (shared ground?), and industrial loads like big motors working better with multiple phases.

@@straightpipediesel only for long distances

Even in my engineering my prof explained in a similar way.. Which i dont remenbet exactly.

Excuse me sqrt of 3 is for the balance supply so it doesnt have to be sqrt of 3 thats just the factor

Cabron Sliver if you go through the development of power capacity you will that the what is inside the square root is directly related to the number of conductors. It is not a supply balance factor.

Please help shreekanthadpad@gmail.com

dsrekjw say it again with more simple words please!

The explanation is really simple: three is the minimum amount of points to represent a vector in two dimensions. As rotational movement is in two dimensions you need three phases. If you wanted to move a ball in three dimensions you would need four phases (forming a three sided base pyramid)

@@nirodper you made it even more complicated

3 phase devices humm too. Just stand next to a transformer. The hum is due to magnetostriction and its frequency is either 50 or 60 Hz.

What happened then?

A great reply which took me 1/10th of the time to read as to watch the video.

240/415 UK ??? We had 220/380 on the european continent, but that was decades ago. As far as I know, both have 230/400 now.

@@ronaldonmg It is the same ratio .... just a different starting voltage! Europe is now 230v ;0)

Wow. A direct, honest, and respectable comment. You rock.

Very close to constant. Why reinvent the wheel. 3-phase has worked well for over 100 years.

And smoke a fatty:).

Sky - decaf aint gonna help keep you awake.

i wish i could still sit with my grandfather, talk and also record it

I have sat with one of his ilk. We were doing a project on monitoring induced currents from Aurora on the Fairbanks to Anchorage inter-tie . Professor Bob Merritt, RIP. The point regarding additional breakers at the sub-station is only the beginning. The switching for capacitors to achieve the R Factor due to predominant inductive loads would certainly be interesting. That is only a drop in the bucket.....

You lost me at decaf

For 3 Phase versus Single Phase It is actually 50% more cost (in wire, insulators and switching) gives 3 times the capacity or a 200% increase.

You miss the point. If you have limited ROW and need more power, you can effectively intersperse a second three-phase line with the first one to get the doubling of power without a new ROW or adding ROW width for a second three-phase line.

Too bad you did not make this video because you answer the questions he fails to answer. Thank You

Yeah - but you STILL need a 4th wire for ground.

What is "psychical wire size"!??

michaelovitch I have the same question. Please someone explain it to me too.

You misunderstand what 2-phase means. "2 phases, each on the opposite side of the shaft" is actually single-phase - a 180 degree phase shift is just the opposite polarity of a sinusoid. Two-phase power has phases 90 degrees apart. Most single-phase motors start by using a capacitance to generate a second phase during startup. The main reason for the popularity of 3-phase power is that if you balance the loads on the phases, you don't need a return "neutral" line, so you only need three wires. This doesn't work for 2-phase - you still need three wires.

The thought exercise here is, "If 3 phases is more efficient, more powerful, and just better... why not more phases?"

@@BrightBlueJim ... how do they go about balancing the loads? So, if you have 3 phase power connected to a 3 phase motor, you would have a balanced load, correct? I'm gonna have to study balanced loads until it makes more sense...

@@truthbebold4009 A 3-phase motor is always a balanced load. It has the same number of turns on each of the windings, and each winding is powering the motor for part of the time. Rotor inertia helps ensure that the load is spread over all of the phases, even if the mechanical load is higher in some shaft positions than others. I only mentioned balanced load because if you run a building on 3-phase power, many of your loads are single-phase, so they're not automatically balanced. You have to design the building wiring such that there will be approximately the same amount of load on each phase, or you end up wasting money because of the extra copper you're not really using. Three phase power, when designed to use the same amount of power on each phase, saves copper cost, because single phase loads are wired from one phase to another, and all of the current from one phase returns on another. So there is no need for a neutral wire.

Its cutting the distribution loss in half that makes 3Φ power desirable. 3Φ power is the smallest number of phases that create a virtual ground removing half of the the resistance (aka copper) loss incurred distributing the power. The phasor sum of equal load currents from all 3 phases to ground cancels out and there is no net ground current. 1Φ clearly has a hot and a ground. 2Φ at 180° still requires the current to travel both out and back for 2-way round trip copper loss. Its more plainly equivalent to 1Φ hot-ground when you realize "ground" is an arbitrary designation so choosing 1 of the 2 as ground or physically connecting one of them to ground return to a simple hot-ground 1Φ system again. 2Φ at 90° requires a 3rd wire to be ground but only a fraction of the balanced load current cancels at the ground terminal. But since it need 3 wires you can drive all 3 wires 120° offset and cancel a;; the ground current instead and deliver more power with the same installation cost. Any number of phases 3 or greater can be used to cancel out each other's ground current out. but a number greater than 3 provides no additional benefit, it only increases the cost of wiring and equipment. A 3Φ induction motor can start and run at the line frequency, but as noted a 1Φ induction motor that runs at the line frequency doesn't have any average torque starting from 0RPM and may randomly spin up in either direction unless something is added to split the phase to create starting torque. For fractional horsepower motors the cost of 3 windings and building wiring isn't justified and torque is created by splitting the single phase electrically with another winding at an offset angle either as a coil (split phase motor) or a capacitor (capacitor split phase aka permanent split capacitor or psc motor) in series with the main winding or by creating torque magnetically using the wider soread of the high stalled rotor magnetic flux with a shorted turn (shaded pole) to create a net torque . The electrical phase splitting can be combined with a starting switch to disconnect the starting winding after the motor starts. It can be as simple as a positive temperatur coefficient resistor (used for small refrigerators and A/C) or timer relay (most typically used one-size-fits-all repair part) a centrifugal switch on the motor shaft (for low lifetime start count applications) or a relay that opens when either the start winding current falls below a specific value or the voltage rises above a specific value. There are also 1Φ induction motors that also use a reduced excitation of the extra winding to achieve a higher running torque. Sometimes they use the same basic scheme, e.g. the CSCR capacitor start capacitor run motor, or different schemes like the CSIR capacitor start induction run motor that connects the start winding and a series capacitor in parallel with the main winding to start and switches to run by removing the capacitor putting uses the two windings in series.

fla playa I think I met the guy. Wasn't it him who said that when a fuse blew it was because it pulled too much power?

jgstargazer May have been. This guy would ask you to lift him up and rotate him, as he grabbed a hold to change that fuse.

This video's presenter is a carbon copy of the lecturer who taught this subject when I was at University. Besides looking the same, they shared a knack for repeating points and making many hand gestures but never really understanding which concepts were easy/hard or answering the right question. I agree, the subject of electrical power transmission makes a good sleep aid!

That's not economically efficient.

Although I liked this explanation, I have to say that I laughed out loud at your comment.

im sure its a very effective tool!

Its dry subject may be, had one interesting instructor for Pwr. Trans. course but he hardly ever taught the subject matter!

Right. EE education starts at DC (remember PIEs and EIRs?), then moves on to AC in the 2nd semester.

It wasn't a case of diminishing returns, it was a case of negative return: double the complexity and and double the costs to not even double the power. I wonder why they even bothered to build a model of a 6-phase line. Just run an independent 3-phase line.

***** Say what?

Notice the interleaving of the second three-phase line with the first, and of the second six-phase line with the first six-phase line. The benefit is very high power levels on an incredibly compact ac line.

***** Is it any more compact than DC?

ApolloWasReal As I recall, an equivalent six phase line can be much shorter than an HVDC line and somewhat narrower. Ground clearances are quite modest because the line-to-ground voltage is relatively low for the amount of power handled. The larger number of conductors may make an HPO line equally or more visible in spite of its modest stature.

***** Interesting. Let's see... assuming a phase-neutral voltage of 1V and a 6-way wye (asterisk?) load with a 1 ohm resistor from each phase to neutral there would be no neutral current and the total power would be 6W. The power per phase conductor would be 1W, same as 3-phase. One difference is that the voltage between adjacent phases (A-B, B-C, etc) is only 1V. Non-adjacent, non-antipodal phases (A-C, A-E, B-D, etc) are 120 deg apart so the voltage between them is the same as the 3-phase phase-phase voltage: sqrt(3) = 1.732V. And opposite phases (A-D, B-E, C-F) are 180 deg apart so the voltage between them is 2V. Not sure what practical effect this has on an aerial line where the phase-to-neutral voltage that dictates the amount of insulation required. So for all practical purposes this is just two 3-phase circuits, with a higher voltage between some of the conductors than you'd see in 3-phase, and twice as many transformer windings. But the lower voltage between adjacent phases might allow more compact buried cable designs. I'd have to model it, but the electric and magnetic fields at medium distance from a 6-phase aerial line might be lower than a 3-phase line carrying the same power. That would decrease losses. But it would still have inductive and capacitive losses that are completely absent in a DC line.

Who the hell does he sound like? Its like hes narrated a movie or something I've seen before.

You are absolutely right.

You don't get 'stuck' on direct current, you get stuck on alternating current. Pedantic, I know :D

Dennis S the problem with ac is the skin effect. you see, tesla hadn't forseen this. neighter edisson. but at high power/high frequency there is such thing as a skin effect...where in the electron flow is not going trough the entire conductor, they flow trough the outher edges of the conductor...thus the skin effect. nuclear power plant output stations send the power to the natuonal power distribution grid via tubes, pipes... thats why..in the near future, where electric vehicles are foreseen, dc main distribution lines make more sense, also dc does not have inductance and capacitance losses.

ihavecojones - the bus bars I install are kidney shaped.

Actually it's not a problem, and Tesla made use of the effect in his demonstrations. He also tried to get a deal with some Natural Gas companies to use their copper pipes to conduct alternating current as well as gas. The gas companies were scares of sparks and refused.

+Enigma758 The voltage you can obtain per foot of conductor theoretically of course will remain the same

+Enigma758 He's talking about the voltage difference between the different wires. So if you look at two of the wires in the three phase line and they're 3 feet apart with a voltage difference of 120,000 volts, and then you put a wire between them it would be 1 1/2 feet from each of them and have a voltage difference of 60,000 volts from each of them so either way you have 40,000 volts per foot across the air gap between the conductors. Since the gap needed between the wires is determined by their voltage difference, this means that you don't have to move the original 3 phase wires any further apart to add the 3 offset phases to make 6 phase, so the suspended bundle of wires would take up the same space, but carry almost twice as much power.

jasexavier this is an excellent explanation. Thanks

But why 'almost' twice as much power? Why not *exactly* twice as much?

Power loss to heat.

toffolotty What, so you can slow it down to learn more quickly?

Holy crap. 0.5x made me instantly shitfaced drunk watching this. Fantastic.

The power of 3,6,9 as he always said. It would make a triangle. A triangle is the simplest geometric shape that can house a perfect circle/most efficient angular wave pattern. So think of it as this. Why would I make a 6 sided shape to house a circle when I can do it with 3?

In the last 70 years there are no motors that would benefit from smother controls. Maybe in a confined system like a nuclear submarine but never in industry or domestic usages.

It is a myth that edison did not research AC as an engineer.

No. Edison stole everything from others - just like Apple & Jobs.

That's the myth, Mikey.

@@mikeymcmikeface5599: And you were there watching! That's awesome. What did he do with "everything"?

Agreed! he was too busy electrocuting elephants and dogs to try to prove DC superior. Ironically, DC of the same voltage potential is more dangerous because Dc has no zero crossing

Mizhidor - I wonder if you would have gotten the same recommendation if you had to wake up from your floor. Or if you didn't just wake up at all. Hmm

@@onekerri1 I do occasionally wake up from the floor

That's good, but, on the other hand, I hate to see an inquisitive mind wasted by staring into a little bitty screen.

switch it off amigo

Tesla is rolling over in his grave.

The reason why his idea never got used is because electronic conversion to DC got a lot more efficient. Instead of 6 and 12 phase, we are now using HVDC transmission, or zero phase. So Edison did win.