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Because they rotate at synchronous speed, the speed which is fixed by supply frequency & no. of poles. This speed is independent of load connected to it.
Synchronous speed = 120*frequency/no. of poles
it is that type of generator in which stator field and rotor field rotates at the same speed. in synchronism). in this case rotor acts as a separately excited magnet and it is driven by prime mover. stator delivers the power.
first of all i shotly difine synchronous machne it is electrically operated machine when frequency fixed to the no of poles as we know that that the folling voltage drop ocuur in this machine reactants drop armature resistence drop and armature reaction drop reactant dropoccur due to armature reactenceand resistive drop due to armature resestantnce as we know that armature reaction depend upon the leacage reactentenceand armature reactence so the sum of these to value are called synchronous impedence it is denote by zs=xa+jxl
It is the type of generator most commonly used in a grid power supply system. The generator runs at synchronous speed, 3000 rpm on a 50 Hz system or 3600 rpm on 60 Hz. The rotation speed of all the generators determines the system frequency.
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Difference between synchronous generator and synchronous motor?
ASYNCHRONOUS is a mode whereby events happens irregardless of control. SYNCHRONOUS are this same events but controlled by a timing and/or control
Why do you use induction generators in wind generation rather than synchronous generators?
If you use synchronous generator... you need rotor to rotate always in synchronous speed... practically it s not possible always to produce that speed by air flow... Air flow always varies...But using induction generator, you need to get speed to make slip as positive value.. it is always possible...so induction generator is best one..
When slip ring get negative charge in ac generator?
you apply dc voltage to slip rings in synchronous generators polarity will make no difference ( other than when it is first applied )
Why synchronous motor is called synchronous capacitors?
A synchronous motor can operate as either a Generator or a Motor.When a synchronous motor has current applied to the windings on its rotor and the stator is energized with say a 50hz line supply (with little or no physical load) then the exact amount of excitation provided by the rotor can determine whether the stator displays inductive or capacitive properties.If the rotor is under excited (too Little rotor current) the Synchronous Motor will behave as an Inductor, however if the rotor is over excited then the Synchronous Motor will behave like a Capacitor.Hope this helps
Why the DC motor is call as synchronous motor?
A 60Hz synchronous motor spins at synchronous speed - if it's a two pole motor it will spin at exactly 1800 rpms. An asynchronous motor will spin at a speed lower than the power supply frequency - a symilar asynchronous motor may spin at 1700 rpms.
Which type of generator is used in windmills?
Synchronous generators
Why do power stations use synchronous generators and not induction generators?
This is not entirely true. In small power stations not connected to grids and wind turbines they usually use induction generators instead of synchronous for their capability of producing energy at varying rotor speeds and their price which is lower the synchronous generators. Before I tell you why they use synchronous in big power stations connected to the grid you must know that usually you have more than one power plant connected to the grid. And if you want the power of each power plant to be added to the grid you need the all the alternating currents to be in phase so the frequency must be the same. And as you probably know they are called SYNCHRONOUS generators because the speed of the rotor (the frequency) is the same as the AC supply current. So obviously it will be much easier to control the frequency of a synchronous generator and therefore easier to synchronize with the grid.
Difference between synchronous generator and synchronous motor?
ASYNCHRONOUS is a mode whereby events happens irregardless of control. SYNCHRONOUS are this same events but controlled by a timing and/or control
What happen if a prime mover fails when two generators are in parallel?
It acts as synchronous motor by consuming power from the other generator....
Why do you use induction generators in wind generation rather than synchronous generators?
If you use synchronous generator... you need rotor to rotate always in synchronous speed... practically it s not possible always to produce that speed by air flow... Air flow always varies...But using induction generator, you need to get speed to make slip as positive value.. it is always possible...so induction generator is best one..
What conditions are necessary for paralleling two synchronous generator?
•The RMS line voltages of the two generators must be equal.••The two generators must have the same phase sequence.••The phase angles of the two a phases must be equal.••The frequency of the new generators, called the oncoming generator, must be slightly higher than the frequency of the running system.
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 a synchronous generator?
Synchronous generators are the majority source of commercial electrical energy. They are commonly used to convert the mechanical power output of steam turbines, gas turbines, reciprocating engines and hydro turbines into electrical power for the grid. (OR) A "synchronous" generator runs at a constant speed and draws its excitation from a power source external or independent of the load or transmission network it is supplying. A synchronous generator has an exciter that enables the synchronous generator to produce its own " reactive" power and to also regulate its voltage. Synchronous generators can operate in parallel with the utility or in "stand-alone" or "island" mode. Synchronous generators require a speed reduction gear
Can a synchronous generator be driven on variable speed?
Synchronous generators are traditionally driven at a constant speed to maintain the fixed frequency of the generated electricity. However, with advancements in power electronics and control systems, it is possible to drive a synchronous generator at variable speeds by using technologies like electronic converters to adjust the frequency of the output power to match the grid.
When slip ring get negative charge in ac generator?
you apply dc voltage to slip rings in synchronous generators polarity will make no difference ( other than when it is first applied )
Is there a website called Generators Best?
There is no website called Generators Best. There are a lot of sites with generator in the name, selling generators and accessories, so the domain name is still available.
Difference between static excitation system?
A static excitation system uses solid-state devices to provide the field coil of a generator with the necessary excitation current. This system is more reliable and requires less maintenance compared to a traditional brush excitation system, which uses brushes and slip rings to deliver excitation current. Static excitation systems are also more flexible and offer better control over the generator's output voltage and reactive power capability.
