Oh my goodness! TonyS answered your question and advised how to learn more. COME ON, do some of this for yourself!
Here: the Wikipedia article on synchronous motors is available in 17 languages.
After reviewing that, have a look at:
Cuckoo Syndrome: Feed me, help me, I'm too weak... this plea continues until you drop dead from helping them.
cuckoo - a bird that lays its eggs in other birds nests so that the surrogate parents raise the offspring, owing to their parental instincts -often leading to the parent birds death from exhaustion.
No, it isn't. The speed can be controlled with a Variable Frequency Drive.
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"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856
A synchronous motor of n poles running on AC of given Hz turns at 720*Hz/n rpm, in synch with the AC. An induction motor turns a few percent slower due to slip; the heavier loaded the more slip.
Thus synchronous motors are rated at rpm's such as 3600, 1800, 1200,... (for 60 Hz) or 3000, 1500, 900, 750,... (for 50 Hz.) But induction motors are typically 3550, 1760, 1175,...; 2950, 1470, 875,..., with small variations depending on design.
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In vino veritas; in cervisia carmen; in aqua E. coli.
Please, go ahead and ask questions if you need to. Sometimes, we get a little bit upset because young guys will place a lot of fundamental questions here so that we do their homework for them, when they do not put much effort into finding the answers themselves. We believe that working hard to discover the answer to school questions is the purpose of assigning the homework questions to the students, and that we would be harming their schooling if we gave easy answers to questions here.
Before you ask questions in the future, it would be helpful if you explain you are 79 and why you are asking the questions here instead of your grandson. As long as you grandson is not asking you the questions for the wrong reasons, I am sure you will find many good people here who are willing to help out. However, technical people are sometimes impolite, because they do not understand how difficult it can be for non-technical people to find the answers to technical questions, even though the internet has very useful tools such as Google, which will find any information you ask it for. The difficulty is that Google will find SO MUCH information that it is often overwhelming for those who are not aware of how it works. This is often difficult for knowledgeable technical people to appreciate.
If you ask a question here again in the future, my suggestion is to begin it by saying: "I am 79, and I am having difficulty finding information on the internet because it is overwhelming to me. I am helping my grandson with his homework, and I need to learn about": Then, follow that with your question. People on this site (CR4) will become familiar with you, and your experiences with them will become much more polite and pleasant. Most of us wish to help, which is why we are here.
There is one other thing which would also help. If you could be more precise when you ask your question, you would get better answers. For example, when you ask "what is the difference between an induction motor and a synchronous motor", to fully answer that would require a very, very long reply which most of us can't take time to write. If you ask more specifically, "can an induction motor be used in place of a synchronous motor", you are asking a question which may be answered in a reasonable way, without too many words. And, in order to ask such a question, you show that you have tried to learn something on your own, before asking here, which is what most people here want from you.
I hope this may help you next time you need to ask a question.
I don't mean to be disrespectful, but perhaps a better thing to teach your grandson is how to do his own homework and research. Doing it for him facilitates laziness, something I deem to be rampant in young people now. That's the main reason some of us get a little testy in here.
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** All I every really wanted to be, was... A LUMBERJACK!.**
Take a textbook and study the construction,characteristics(speed,torque,pf etc), performance etc of both machines.In 1960's we studied a book titled"design and performance of A.C machines" by M.G.Say. There was another book for D.C machines by Clayton
Synchronous vs Induction Motor
Re: Synchronous vs Induction Motor
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