Where Electricity Comes From: History of the Generator & How the Generator Works
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I have tried all variants, 500 VDC burned a whole in my finger and made me sit down for a while. AC lock your muscles so your only choice may be to walk backwards and pull the wire out of your hand. If the wire is long you may die ( 230 V AC ).
Date: 2022-12-27
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Comments and reviews: 18
Nathan
AC current in a three-phase system could be amplified/controlled precisely by the use of transformers and, for each phase separately, by the use of radio-type amplifier electronics (vacuum tubes until recently. This precise control, even when amplified, allowed data transmission to be accomplished between devices that are separated by some distance, yet need to get precise information from one-another and, with enough amplification, to directly control the operation of these long-distance devices (analog, pre-digital controls.
The mechanisms used by the US Navy after WWI, and until modern digital data transfer replaced them, were called Selsyns or, more usually, Synchros. A magnetic needle (just like on a compass, but stronger mechanically) was put on a rotating shaft and a metal ring of three divided sections wrapped around it in the same plane of the rotating needle. Three electromagnets in a triangle were attached to the ring, each separately wired. The other end of the wires of the three coils were attached to a duplicate loop and needle with equal AC power running through each coil on independent circuits. By rotating the needle in one loop, the needle['s magnetism would modify the current in each of the three lines so that the EXACT same change would happen at the coils at the other needle and the magnetic field would, if powerful enough (if necessary, amplified by the vacuum tube/transformer set in-between) move the needle at the other end to match the first needle. This allowed information, when changed to a needle angle value, to be sent from one place to another very accurately. In many cases, when increased accuracy to overcome slop in the needle angles was needed to get really precise numbers, a second needle set using a 36-to=1gearing action would also be sent and the two values merged using precise electronic circuits to give an EXTREMELY PRECISE angle value that could be changed back to whatever kind of information was being transmitted precisely. In fact, by using powerful enough amplification, the needle on the far end coil set could be strong enough to directly rotate the controls of the far-end device, allowing the elimination of the man in the loop for automatic control. US naval guns by the end of WWII were almost entirely controlled in the later fire-control systems using this method, which made accurate gunfire, especially against fast aircraft, possible. This target position and motion information would come from the aiming range-finders/directors tracking the target, be sent to electro-mechanical calculators to give weapon aiming orders, and then sent to the gun mounts, all with minimum human inputs to slow the process.
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AC current in a three-phase system could be amplified/controlled precisely by the use of transformers and, for each phase separately, by the use of radio-type amplifier electronics (vacuum tubes until recently. This precise control, even when amplified, allowed data transmission to be accomplished between devices that are separated by some distance, yet need to get precise information from one-another and, with enough amplification, to directly control the operation of these long-distance devices (analog, pre-digital controls.
The mechanisms used by the US Navy after WWI, and until modern digital data transfer replaced them, were called Selsyns or, more usually, Synchros. A magnetic needle (just like on a compass, but stronger mechanically) was put on a rotating shaft and a metal ring of three divided sections wrapped around it in the same plane of the rotating needle. Three electromagnets in a triangle were attached to the ring, each separately wired. The other end of the wires of the three coils were attached to a duplicate loop and needle with equal AC power running through each coil on independent circuits. By rotating the needle in one loop, the needle['s magnetism would modify the current in each of the three lines so that the EXACT same change would happen at the coils at the other needle and the magnetic field would, if powerful enough (if necessary, amplified by the vacuum tube/transformer set in-between) move the needle at the other end to match the first needle. This allowed information, when changed to a needle angle value, to be sent from one place to another very accurately. In many cases, when increased accuracy to overcome slop in the needle angles was needed to get really precise numbers, a second needle set using a 36-to=1gearing action would also be sent and the two values merged using precise electronic circuits to give an EXTREMELY PRECISE angle value that could be changed back to whatever kind of information was being transmitted precisely. In fact, by using powerful enough amplification, the needle on the far end coil set could be strong enough to directly rotate the controls of the far-end device, allowing the elimination of the man in the loop for automatic control. US naval guns by the end of WWII were almost entirely controlled in the later fire-control systems using this method, which made accurate gunfire, especially against fast aircraft, possible. This target position and motion information would come from the aiming range-finders/directors tracking the target, be sent to electro-mechanical calculators to give weapon aiming orders, and then sent to the gun mounts, all with minimum human inputs to slow the process.
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titicoqui
WARNING; FASCINATION IN THE EXTREME, VIEW AT YOUR OWN RISK Sometimes kids go to college to be lawyers and accountants and then by curiosity and accident they happen to get a professor like kathy in some elective and almost immediately begin to despise accounting or law, preferring to pursue physics as if nothing else mattered but the ultimate in matter, matter itself as revealed in physics and perhaps in nano chemistry alone. the late charles krauthammer, perhaps the most astute political analyst of our generation openly confessed with exceeding sorrow, that he had to switch his studies to medicine, psychiatry, because he fell short of the sheer brilliance and cognitive talent needed to do quantum physics on a professional level. for him it was like finally giving up pitching in the major leagues to be an obscure catcher in the little leagues, he was sufficiently familiar with the often arcane, recondite and abstruse shop talk of guys like dirac, schrondiger, pauli, feinman, born, bohr to gracefully shrink back and so nobly and humbly pursue his own unique genius, political analytics and insights second to none,
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WARNING; FASCINATION IN THE EXTREME, VIEW AT YOUR OWN RISK Sometimes kids go to college to be lawyers and accountants and then by curiosity and accident they happen to get a professor like kathy in some elective and almost immediately begin to despise accounting or law, preferring to pursue physics as if nothing else mattered but the ultimate in matter, matter itself as revealed in physics and perhaps in nano chemistry alone. the late charles krauthammer, perhaps the most astute political analyst of our generation openly confessed with exceeding sorrow, that he had to switch his studies to medicine, psychiatry, because he fell short of the sheer brilliance and cognitive talent needed to do quantum physics on a professional level. for him it was like finally giving up pitching in the major leagues to be an obscure catcher in the little leagues, he was sufficiently familiar with the often arcane, recondite and abstruse shop talk of guys like dirac, schrondiger, pauli, feinman, born, bohr to gracefully shrink back and so nobly and humbly pursue his own unique genius, political analytics and insights second to none,
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Mikiness
Since you like physics AND history, I have some for you.
On the RMS Titanic, there were four100 volt DC generators & 2 backup.
Wattage unknown to me, but they had to be massive as they had to power all of the incandescent bulbs plus the very new technology of electric heaters in 1st class (2nd & 3rd were heated using steam radiation.
I do not believe thermostats had been invented at the time, meaning they were all the way on or off.
The electricity was also used for the new tech of wireless telegraph on board.
I am off grid here in Fukuoka Japan and just happen to be powered the same way except via solar (100 volt DC / 8000 watts. I should note, higher voltage DC needs to have spark arrestors (capacitors) on EVERY switch as the power has no zero crossing as AC does, lending itself to arcs. DC wants to continue when opened.
I have no knowledge of how this was mitigated on Titanic.
A question I can find no answer to: 100 volts DC in sea water will split the Hydrogen and the oxygen of H20 causing me to wonder if that was an issue as it was sinking before power loss.
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Since you like physics AND history, I have some for you.
On the RMS Titanic, there were four100 volt DC generators & 2 backup.
Wattage unknown to me, but they had to be massive as they had to power all of the incandescent bulbs plus the very new technology of electric heaters in 1st class (2nd & 3rd were heated using steam radiation.
I do not believe thermostats had been invented at the time, meaning they were all the way on or off.
The electricity was also used for the new tech of wireless telegraph on board.
I am off grid here in Fukuoka Japan and just happen to be powered the same way except via solar (100 volt DC / 8000 watts. I should note, higher voltage DC needs to have spark arrestors (capacitors) on EVERY switch as the power has no zero crossing as AC does, lending itself to arcs. DC wants to continue when opened.
I have no knowledge of how this was mitigated on Titanic.
A question I can find no answer to: 100 volts DC in sea water will split the Hydrogen and the oxygen of H20 causing me to wonder if that was an issue as it was sinking before power loss.
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Tomie
Your not looking deep enough. The magnetic field induces the EMF. I was addressing your usage of created. I respect your knowledge, you are a good teacher. We, the Human race does not create anything (except, trouble. ) I am impressed at your research, you are very through. I would love to talk to you about these things. It would be a good time. For one thing, their is no such thing as SOLID. I had a professor that said, If I punched this (concrete wall with my index finger long enough, the molecules in my finger and the molecules of the concrete would allow my finger to pass into the concrete) Just an example. My thought, how would you get your finger out?
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Your not looking deep enough. The magnetic field induces the EMF. I was addressing your usage of created. I respect your knowledge, you are a good teacher. We, the Human race does not create anything (except, trouble. ) I am impressed at your research, you are very through. I would love to talk to you about these things. It would be a good time. For one thing, their is no such thing as SOLID. I had a professor that said, If I punched this (concrete wall with my index finger long enough, the molecules in my finger and the molecules of the concrete would allow my finger to pass into the concrete) Just an example. My thought, how would you get your finger out?
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ghh
Fabulous videos Kathy. Just a couple of points: the DC dynamo was improved by a Belgian called Zenobe Gramme, which oddly enough anglo saxon scientific history is mostly unaware of, you may want to research his work. And AC current is more dangerous, the human ( or animal body) acts as a capacitor in AC current. Capacitors let AC current pass through, and the capacitive reactance (resistance to AC current) is around 3 orders of magnitude less than dry skin resistance at the same voltage. Keep up the good work!
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Fabulous videos Kathy. Just a couple of points: the DC dynamo was improved by a Belgian called Zenobe Gramme, which oddly enough anglo saxon scientific history is mostly unaware of, you may want to research his work. And AC current is more dangerous, the human ( or animal body) acts as a capacitor in AC current. Capacitors let AC current pass through, and the capacitive reactance (resistance to AC current) is around 3 orders of magnitude less than dry skin resistance at the same voltage. Keep up the good work!
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RHIANN
nice! where at that time perhaps they could not find a very a strong magnet for the rotor or commutators so they went for an electro magnet instead but now a days we could find small yet very powerful magnets thus we can replace either the rotor or commutator with these powerful magnets, the result is a much a higher output of electricity with the same input power from what ever source. but magnets alone could not create electricity it must be a combination of electro magnet and permanent magnet.
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nice! where at that time perhaps they could not find a very a strong magnet for the rotor or commutators so they went for an electro magnet instead but now a days we could find small yet very powerful magnets thus we can replace either the rotor or commutator with these powerful magnets, the result is a much a higher output of electricity with the same input power from what ever source. but magnets alone could not create electricity it must be a combination of electro magnet and permanent magnet.
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Robert
So funny now to think it took so long to try AC rather than unfiltered DC for arc lighting, because it seems so obvious! I guess to their minds there was something about polarity that they thought was necessary to the ordinary operation of an arc lamp, even though the polarity was not in the carbon gap as built. Maybe they thought that the current going back and forth would cancel its effect out.
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So funny now to think it took so long to try AC rather than unfiltered DC for arc lighting, because it seems so obvious! I guess to their minds there was something about polarity that they thought was necessary to the ordinary operation of an arc lamp, even though the polarity was not in the carbon gap as built. Maybe they thought that the current going back and forth would cancel its effect out.
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Colin
The video forgot to mention this fact: Permanent magnets were originally very weak and very expensive. The strength of the magnetic filed from the magnet determines the maximum energy you can get from a generator. By using an electromagnet, the output from a generator could be increased enormously. But it takes a few percent of the generated electricity to power the electromagnets.
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The video forgot to mention this fact: Permanent magnets were originally very weak and very expensive. The strength of the magnetic filed from the magnet determines the maximum energy you can get from a generator. By using an electromagnet, the output from a generator could be increased enormously. But it takes a few percent of the generated electricity to power the electromagnets.
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Bob
The common automobile alternator is a battery-excited, 3 phase ac generator rectified to dc using a diode bridge. The crudest, often found in motorcycles, can be a 2 phase, permanent magnet alternator also rectified into useable dc with a diode bridge. Cruder yet is the Magneto generating ignition voltages found on power plants from lawnmowers to airplane engines.
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The common automobile alternator is a battery-excited, 3 phase ac generator rectified to dc using a diode bridge. The crudest, often found in motorcycles, can be a 2 phase, permanent magnet alternator also rectified into useable dc with a diode bridge. Cruder yet is the Magneto generating ignition voltages found on power plants from lawnmowers to airplane engines.
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The
Thank you, Kathy. This was informative and helpful. I already understood the basic physics of generation. But I wanted to understand more about the history and engineering that led to modern generators. I loved learning about the work of Samual Varley and Werner Siemens and many others. An excellent video!
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Thank you, Kathy. This was informative and helpful. I already understood the basic physics of generation. But I wanted to understand more about the history and engineering that led to modern generators. I loved learning about the work of Samual Varley and Werner Siemens and many others. An excellent video!
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mdb123
I think it is astonishing. Although everything is quantum and probabilistic fields, electricity and electromagnetism still works not only to power our gadgets and run our software, but in every aspect of cell machines powering our bodies and providing the lush life on Planet Earth. It is astonishing.
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I think it is astonishing. Although everything is quantum and probabilistic fields, electricity and electromagnetism still works not only to power our gadgets and run our software, but in every aspect of cell machines powering our bodies and providing the lush life on Planet Earth. It is astonishing.
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Susil
1885 Galileo Ferraris had the prototype for the same 2-phase gen/ motor [ poly phase] for the 1st time. This was 2yrs before the Tesla's. And our perfected 3-Phase 3wire Star/Delta system was by the Dolivo Dobrovolsky in 1897. May be you wanted to shorten the video so didn't mention all this details.
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1885 Galileo Ferraris had the prototype for the same 2-phase gen/ motor [ poly phase] for the 1st time. This was 2yrs before the Tesla's. And our perfected 3-Phase 3wire Star/Delta system was by the Dolivo Dobrovolsky in 1897. May be you wanted to shorten the video so didn't mention all this details.
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Tomie
Kathy, generators DO NOT create electricity! Does the term electromotive force ring any bells. Please do not misunderstand me, I love your science shows. According to the laws of thermodynamics, we can not create energy or destroy it.
Kathy, do you remember Mr. Wizard. early 1960's.
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Kathy, generators DO NOT create electricity! Does the term electromotive force ring any bells. Please do not misunderstand me, I love your science shows. According to the laws of thermodynamics, we can not create energy or destroy it.
Kathy, do you remember Mr. Wizard. early 1960's.
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hubercats
Nicely done! Im an electrical engineer and Ive always enjoyed learning about technology through the lens of history. I also think that students understand math much better by relating it to physics rather than just teaching it as a set of abstract concepts. Keep up the great work!
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Nicely done! Im an electrical engineer and Ive always enjoyed learning about technology through the lens of history. I also think that students understand math much better by relating it to physics rather than just teaching it as a set of abstract concepts. Keep up the great work!
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Gerard
There are people rising up on yt who are showing themselves to be first rate teachers, Professors, doctors and producers of original material of the highest rank. I have never been so well tought while wasting no time in boring lectures. Cathy is fabulous and so is Dr. Erick Berg.
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There are people rising up on yt who are showing themselves to be first rate teachers, Professors, doctors and producers of original material of the highest rank. I have never been so well tought while wasting no time in boring lectures. Cathy is fabulous and so is Dr. Erick Berg.
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Allan
In my power engineering classes we were taught that self excitation was started by the small residual magnetism left in the iron cores when they were not turning (hysteresis.
Maybe we should measure the refusal to give someone credit for an idea in units called Varleys.
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In my power engineering classes we were taught that self excitation was started by the small residual magnetism left in the iron cores when they were not turning (hysteresis.
Maybe we should measure the refusal to give someone credit for an idea in units called Varleys.
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WALTER
hi kathy. i live in u. s. a and have never really understand how electrons looks and if they come from the powerplant to our houses and back and if thats the case they travel faster than light. or are they really really slow or we just get their magnitude
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hi kathy. i live in u. s. a and have never really understand how electrons looks and if they come from the powerplant to our houses and back and if thats the case they travel faster than light. or are they really really slow or we just get their magnitude
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Rob
After all these years I'm still at odds, or puzzled not by what a generator is generating (current and voltage, but what exactly is at play at generating electrical power. I would argue that generators actually collect and concentrate (align) power.
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After all these years I'm still at odds, or puzzled not by what a generator is generating (current and voltage, but what exactly is at play at generating electrical power. I would argue that generators actually collect and concentrate (align) power.
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