Aσυχρονο μοτερ σαν γεννητρια

η χρηση ενος απλου μοτερ σαν γεννητρια εχει περιγραφει στο θεμα 
''ανεμογεννητριες μικρες και μεγαλες''  οπου χρεισημοποιηται για την ευκολη διασυνδεση του στο δυκτιο
σε αυτο το θεμα μεταφερω ενα ωραίο αρθρο οπου 
περιγραφεται πως μπορουμε να χρησιμοποιησουμε ενα ασυχρονο μοτερ σαν γεννητρια ανεξαρτητη 
απο 
συνδεση στο δυκτιο μα με χρηση πυκνωτών για την αρχική διέγερση 


το αρθρο ειναι στα αγγλικά.

An Easy to Build and Operate Induction Generator
 

Believe it or not, nearly everyone you know has at least one induction generator and probably more. That's right! You say that is impossible... well, read on!
 
Within every home in America there are motors that can be operated as generators. They may not be labeled as generators, but they will function just the same. These motors are often called "squirrel cage motors" and are in washing machines, dryers, water pumps and other devices too numerous to me

Typical electric squirrel cage motors

Besides being numerous and cheap, they will generate AC voltage of the purest sinewave. They use no brushes and do not produce any RFI.(Radio Frequency Interference) A motor converted to an induction generator will power flouresent and incandesant lights, televisions, vcr's, stereo sets, electric drills, small power saws and other items.
OK, what is so great about it? There is nothing complicated about the conversion, no weird rewiring, no complicated math...nothing! There are no brushes to wear out.
They can not be overloaded; if too much of a load is applied to the generator, it simply quits generating. Removing the load will usually cause the generator to start again. Speeding up the motor will help if it doesn't start right away.
 


The generator will not start under a load. Not a problem! You shouldn't attach any load to a generator until it is at running speed. This is actually kind of a fail-safe feature.
So far, that is about all of the problems that I've found and I consider those minor.

How do you convert one?

 
By adding capacitors in parallel with the motor power leads, and driving it a little above the nameplate RPM, (1725 RPM ones need to turn at approximately 1875 RPM, and 3450 RPM ones at 3700 RPM) the motor will generate AC voltage! The capacitance helps to induce currents into the rotor conductors and causes it to produce AC current. The power is taken off of the motor power leads, or the capacitor leads, since they are all in parallel.
This system depends upon residual magnetism in the rotor to start generating. Almost all the motors I've tried begin generating just fine on their own, with the appropriate capacitor connected of course! If it doesn't start generating, try speeding the motor up. That will usually get it going. However, it is extremely rare to find one that doesn't start.
If a motor doesn't start generating on the very first try, then apply 120 vac or even 12 or more volts DC to the motor for a few seconds. That will usually work to magnetize the rotor and your generator will start by itself from then on.
It is important to not shut the generator down with a load connected to it. This tends to demagnetize the rotor and can cause it to not self-energize. That is, the motor will turn, but it will not produce voltage. It is not a serious problem since the rotor can be remagnetized by following the instructions in the paragraph above.
I've only found one motor that would not consistantly generate (out of a dozen or so that I've tried over the years) and it was one with a bunch of wiring coming out of it; it may have been a multi-speed AC motor. I had a 120 volt AC relay in the circuit that temporarily added a 200 uf starting capacitor across the permanent 160 uf running capacitor (Using the Normally Closed contacts) to get it generating. When 120 volts was produced, the relay contacts opened up and removed the 200 uf from the circuit. That worked, but it was not dependable. I just gave up on that one.
The capacitors used must be the type designated as "running" capacitors and NOT "starting" capacitors. Starting capacitors are used for a very short time, usually less than a second or two, and would be destroyed by being connected across the AC line continously. Running capacitors are designed to be connected while the motor is powered.
NOTE: Make sure the caps say, "NO PCB's". PCB's aren't used anymore for capacitor construction because it was a dangerous chemical composition. If the caps are old, and you are not sure, don't use them. Be safe!
It is necessary to experiment to find the best value of capacitance to get one working. Start with about 150 to 200 uf for motors 1 horsepower and under. More capacitance equals more voltage output. The final value should be able to produce about 125 VAC when it is putting out 60 hertz with no load. Then plug in100 watt light bulbs until the voltage drops to what ever lower limit you set. Mine will do about 1050 watts before dropping to 105 VAC.
 
 

Typical Running Capacitors...GOOD! .......................Starting cap...Bad!

λογο του οτι υπαρχει μια συνχυση στο τι ειναι συνχρονο μοτερ και τι ειναι ασυχρονο συν λιπες εξηγησεις για 
αλλες μορφες ηλεκτρικου κινητηρα εναλλασσομενου ρευματος 
βρηκα 
αυτην την πολυ καλη διπλωματική εργασία.


αξιζει να διαβαστει=[url=http://users.teilar.gr/~trogadas/MIXANES/MIXANES AC/THEORIA AC.pdf]http://users.teilar.gr/~trogadas/MIXANES/MIXANES%20AC/THEORIA%20AC.pdf[/url]