This is perfectly timed for me as I am designing a microhydro system, trying to decide on the best generation/transmission gear for maximum efficiency. Thank You!
Stay in touch. DFIG in the works but it's going to take some time to get there. Check out the update at: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-VdBqHQuxpeQ.html
Hi Jim, very pleasing to see systematic coverage from minus to positive on the cliff. Minor nits, it would be itch scratching to see 6,7,8,9 dots on the cliff, as well as two points in the plateau. However, very nice presentation.
Thanks for the videos! 😎 If possible could you let me know if I’m on the right track with this: An asynchronous generator only needs a mechanical medium to engage input & output….but a synchronous generator would need an electrical (control) medium to make the connection. *Ultimately the physical connection would be mechanical but the preparation would need to be done while measuring both sources and synchronizing them with each other beforehand ? -This question is based on my limited work with cogeneration units.
Stay in touch as I'll be publishing lectures on synchronous motors, synchronous generators, and synchronization this fall. Yes, a synchronous generator not only necessitates a mechanical source but also electrical control. By varying the field intensity and rotational speed one varies the voltage magnitude and frequency. Once everything is in synch one closes a contactor to establish connection to the gird. Once synchronized there's an additional electrical interplay as one exports more or less real and reactive power.
Great video lecture sir! Are synchronous generators/motors going to be next soon? There aren't any yet in the playlists. It would make the series more complete and more helpful for engineering students taking electrical machines courses since up to synchronous generators are discussed in the courses, diving into cylindrical-rotor pole & salient-pole rotor types, which unfortunately only few cover in RU-vid. Again, thank you very much sir for your lectures. Very comprehensive, insightful, and engaging.
Hey Jim. Thanks for all your effort in the presentations of your videos. As an engineer, I really appreciate all of this free information. I do have one question on the Position 1 "No Load" graph right at the 19:56 time point of the video. This will pertain to all five postion graphs as well. The power curve on these graphs are plots of the apparent power correct? Measured in Volt-Amps. If the power curve is bipolar and symetrical, average value of the curve is zero. Purely reactive and no transduced power measured in watts. If the curve is bipolar and asymetrical or even all unipolar, then the curve will have a finite average value and will have a transduced power component measured in watt units and have reactive power component measured in VAR units as well. As this is the case in this graph. My question is the part the graph where you have the units per division mentioned, you have "Watts per Division" for the power. Should that be "Volt-Amps per Division"?
In this lecture, the generator rpm was increased in order to increase output, but on every asynchronous generator I've worked on the motor/generator rpm has always remained constant despite load. What lecture should I watch that would help me better understand this?
Soon! i’m actually working on it right now however I’ve got a bunch of pneumatics lectures already recorded edited ready to be released. i’m also working on synchronous motors, synchronous condensers, synchronization, synchroscopes and synchronous generators in the unloaded and loaded condition.
Question Jim: the Pmech formulae is used to calculate what horsepower (Diesel engine)you need to spin an altenator of a particular rating? Say 175 KW+ what amount of HP I need to spin the rotor? Also for hydro-electric, do the calculations of head pressure spinning the rotor follow the same? Thanks for your different approach to mot/gen which I haven't heard!
Hi Jim, i have a question, if dual winding induction generator no load all test is ok, but while synchronous with grid excitation current is very higher than rated current and immediately main MCCB getting trip, this is rewinding induction generator, so if any issue on generator winding ?
Hi professor. I’ve got a question: can the RC type of SPDs “ringing” installed to protect 3 phase compressor motor relay cause the motor to run backwards for a second or two? Compressor stops on “pump down” so there’s almost no gas on intake side to pump, which makes it easy to turn.
I doubt it. SPDs (surge protection devices), regardless of the type, typically protect only the coil of a contactor designed to make or break connection to primary voltage and do not affect the polarity or phase sequence of that primary voltage. This being said some SPDs might induce a small delay in opening or closing.
@@bigbadtech There’s things called “contacts snubber”, usually Transorb or RC type, although not many of them can be bought from outside manufacturer. TC snubber have to be tuned in to the inductive load so they will be effective and will not cause excessive “ringing” Then there’s Arc Suppression Technology with their “NOsparc” suppressors, the nature of which they keep secret.
True dat. Improperly tuned RC types can ring and momentarily cross zero in negative range. I've always preferred the transorb types (two back to back Zeners). I should actually do a lecture on SPDs. This is a good topic.
@@bigbadtech You very well should! This is a case ( not mine) when reciprociting freezer compressor was replaced by scroll compressor and it starts running backwards upon stopping, but it doesn’t get hot after doing that indicating that check valve failed and letting the discharge hot gas coming back. And as every medium or low temp refrigeration system gets shut down on “pump down”, which in turn “empties” the suction side of the compressor, making it easier to free wheel. It also have some European made unknown contactor. So bunch of people in refrigeration community coming up with wild theories as why in the world does that thing do that! 😁 It is also sets the protection device in the compressor it self which monitors winding temperature and phase sequence to set a fault and alarm.
Jim.... speaking of polarity convention before minute 19:02, 4 seconds of silence, then switched to, advanced first quadrant reaction of polarity convention, what is "it's called" in second 19:03?. If I have the right to complaint for an unanswered explanation? Please sagen ist hier if I don't? Then.....simply erase my suggestion und I'll understand without hassle!!, My best considerations!!
