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Synchronous impedance is also known as the EMF method. It is a ratio of open circuits to short circuits, when they both are referred to the same field excitation.
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Why synchronous impedance method of determining voltage regulation is called as pessimistic method?
Because the saturation is not taken into consideration so the impedance calculated is more than the impedance that would have resulted once the saturation is taken into account.-- By Ankit(bigboss0086@gmail.com)
How armature resistance can be determined in a synchronous generator?
synchronous impedance can be calculated by performing oc test and sc test. by oc test,since the armature current is zero Vt=Ef . in short circuit test ,entire emf is consumed in circulating the short circuit current Isc,through the synchronous impedance. Zs=Ef/Isc.= (open ckt. terminal voltage for a certain field current)/(short ckt. current at the same field current)
What is synchronous machein?
mainly alternator,synchronous motor comes under the synchronous machine.a synchronous motor is not a self starting motor.if a synchronous motor moves with more than synchronous speed then it acts as a synchronous generator.
Why is the frequency of a synchronous generator locked into its rate of shaft rotation?
By definition a synchronous generator must be synchronous. If it is not "locked in" it is not a synchronous generator, but an induction machine.
What is the slip of synchronous motor?
A synchronous motor runs at synchronous speed, so there is no slip, or zero slip.
What is Regulation of alternator by synchronous impedance method?
It is conducting OC and SC tests on the given three phase alternator and determining the regulation by synchronous impedance method.
What is the variation of synchronous impedance with the state of magnetic saturation of machine?
in modern trend, synchronous impedance of alternator should be high. If impedance are more than voltage drop across its arm. Wdg. Is more .according to the phasor diagram of alternator if IaXs componant is more than magnitude of induced emf will also be increased.
Why synchronous impedance method of determining voltage regulation is called as pessimistic method?
Because the saturation is not taken into consideration so the impedance calculated is more than the impedance that would have resulted once the saturation is taken into account.-- By Ankit(bigboss0086@gmail.com)
How the synchronous impedence and armature resistance can be determined in a synchronous generator?
synchronous impedance can be calculated by performing oc test and sc test. by oc test,since the armature current is zero Vt=Ef . in short circuit test ,entire emf is consumed in circulating the short circuit current Isc,through the synchronous impedance. Zs=Ef/Isc.= (open ckt. terminal voltage for a certain field current)/(short ckt. current at the same field current)
How armature resistance can be determined in a synchronous generator?
synchronous impedance can be calculated by performing oc test and sc test. by oc test,since the armature current is zero Vt=Ef . in short circuit test ,entire emf is consumed in circulating the short circuit current Isc,through the synchronous impedance. Zs=Ef/Isc.= (open ckt. terminal voltage for a certain field current)/(short ckt. current at the same field current)
What is synchronous reactance in alternator?
The overall reactance of the armature winding is the sum of its leakage reactance plus fictitious reactance, which is known as synchronous reactance (Xs).Xs=XL+Xarwhere XL and Xar are in Ω/phase. Therefore, Xs is in Ω/phase.The impedance of armature winding is obtained by combining its resistance and its synchronous reactance.
What is synchronous machein?
mainly alternator,synchronous motor comes under the synchronous machine.a synchronous motor is not a self starting motor.if a synchronous motor moves with more than synchronous speed then it acts as a synchronous generator.
Which is better high input impedance or low input impedance and why?
That depends on the output impedance. In electronic we use voltage bridging, that is a relative low output impedance to a higher input impedance. Usualy the input impedance is more than ten times higher then the output impedance. An input impedance is called also a load impedance or an external impedance. An output impedance is called also a source impedance or an internal impedance.
What is difference between synchronous motor and synchronous condenser?
a synchronous condenser is over excited synchronous motor under no load
What is the meaning of synchronous in Tamil?
The meaning of synchronous in Tamil is "ஒருவரின் நடப்பு அல்லது இறுதிவார்த்தைக்கு பின்பற்றுவது."
Why 3 phase induction motor is self starting but synchronous motor is not?
the induction motor as soon as you turn on the power the rotating magnetic field is set up. the shorted winding in the squirrel cage see this and builds up a temporary magnet when its up to synchronous speed there is no longer current in the shorted winding in a single pole motor 60hz this speed is 3600 rpm depending on coupling and skew induction motor is always less than synchronous speed. the synchronous motor as soon as you turn on the power the rotating magnetic field is set up the permanent magnet 0 to 3600 rpm in 1/60th of a second this requires all the power you can deliver until you reach synchronous speed a bit hard on the power source smaller synchronous motors sometimes have a squirrel cage and permanent magnets and enough impedance so they dont put a heavy load on the power electric clocks have the shorted windings on the poles self starting hi impedance some older electric clocks didnt have the shorted windings and need to be nudged to get then spinning
Why is the frequency of a synchronous generator locked into its rate of shaft rotation?
By definition a synchronous generator must be synchronous. If it is not "locked in" it is not a synchronous generator, but an induction machine.
