What is ampere turn method?
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What is ampere turn method?
In the ampere-turn method (which is also known as the MMF method), the effect of armature leakage reactance is replaced by an equivalent additional armature reaction MMF so that this MMF can be combined with the armature reaction MMF. Resistance of the armature (or stator) winding per phase.
How the MMF method is measured?
It is done by connecting the dc voltage supply to the stator armature winding and the corresponding current is measured. By doing so, the dc stator resistance is calculated and then by using the formula Rac = 1.6 Rdc the ac stator resistance is determined.
What are the methods of regulation calculation?
Following are the different methods used for predetermination of regulation of alternators.
- Direct loading method.
- EMF method or Synchronous impedance method.
- MMF method or Ampere turns method.
- ASA modified MMF method.
- ZPF method or Potier triangle method.
Why MMF method is called MMF method?
Voltage Regulation of Synchronous Generator By MMF method:- This method is also known as amp – turns method. In this method the all the emfs produced by rotor and stator are replaced by their equivalent MMFs (fluxes), and hence called mmf method.
Why do we calculate voltage regulation?
Voltage (load) regulation is to maintain a fixed voltage under different load. Voltage regulation is limiting factor to decide the size of either conductor or type of insulation. In circuit current need to be lower than this in order to keep the voltage drop within permissible values.
What is the formula for voltage regulation of an alternator?
VNL > VFL: Then V.R will be positive and the power factor will be lagging or unity. Note: V.R under unity power factor is less than voltage regulation under lagging power factor, Case 2: VNL < VFL or VNL = VFL: Then VR will be negative and zero respectively and the power factor will be leading.
What is MMF method of voltage regulation?
MMF Method is also known as Ampere Turn Method. The synchronous impedance method is based on the concept of replacing the effect of armature reaction with an imaginary reactance, the Magnetomotive force (MMF).
What is the formula for voltage regulation?
Load regulation (percent) = 100 x (voltage no load — voltage full load) divided by voltage full load. Line regulation is another measure of voltage regulation.
What is voltage regulation formula?
% Voltage Regulation = (1.06 x P x L x PF) / (LDF x RC x DF) Where: P – Total Power in KVA. L – Total Length of Line from Power Sending to Power Receiving in KM.
What are the three methods of determining voltage regulation?
For large alternators, the three indirect methods are used to determine the voltage regulation they are as follows: Synchronous Impedance Method or EMF method. Ampere-turn method or MMF method of Voltage Regulation. Zero Power Factor method or Potier Method.
What is EMF and MMF method?
EMF is the force that is responsible for driving the electrons in an electric circuit. Magnetomotive force is abbreviated as MMF. MMF is the driving force required to drive the magnetic flux through the circuit.
What is another name of MMF method?
What is the voltage regulator formula?
Using the formula for the output voltage, VOUT= 1.25V (1 + R2/R1). Being that R1=240Ω, our equation is now 5V= 1.25V (1 + R2/240Ω), so R2=720Ω. So with R2 being a value of 720Ω, the LM317 will output 5V if fed an input voltage greater than 5 volts.
How do you calculate the voltage regulation of a 33KV line?
Voltage Regulation for 11KV, 22KV, 33KV Overhead Line
- % Voltage Regulation = (1.06 x P x L x PF) / (LDF x RC x DF)
- RC = (KV x KV x 10) / ( RCosΦ + XSinΦ)
- Required size of Capacitor (Kvar) = KVA1 (Sin ø1 – [Cos ø1 / Cos ø2] x Sin ø2)
- L = [1 – (KVARC / 2 KVARL) x (2n – 1)]
- % Voltage Rise = (KVAR(Cap) x Lx X) / 10 x Vx2.
How do you find the voltage regulation of a circuit?
How do you calculate voltage regulation of a transformer?
So for example, if a single-phase transformer has an open-circuit no-load terminal voltage of 100 volts and the same terminal voltage drops to 95 volts on the application of a connected load, the transformers voltage regulation would therefore be 0.05 or 5%, ((100 – 95)/100)*100%).
Which method of voltage regulation is accurate method?
Which of the following voltage regulation method is accurate? In Potier Triangle or ZPF method, voltage quantities are calculated on emf basis and mmf quantities are calculated on mmf basis. Therefore, ZPF method is most accurate among all these four methods.
What is MMF and EMF method?
How do you calculate line regulation and load regulation?
How to Calculate Line Regulation
- Find the difference between the initial voltage and the maximum fluctuation.
- Divide the change in voltage by the initial voltage.
- Multiply the number obtained in Step 2 by 100.
