Table of Contents
What is saturated and unsaturated synchronous reactance?
As alternator core iron gets saturated, rate of rise of open circuit voltage with field current decreases. On the other hand, short circuit current keeps rising linearly with field current. Therefore, synchronous reactance (Xs) decreases as core gets saturated.
What is alternator reactance?
The reactance is. ‘set’ by the electrical design used for the alternator and is a product of the amount of active. [electrical] components used within the alternator.
How do you determine saturated synchronous reactance?
Saturated Synchronous Reactance Hence, the value of the synchronous reactance to be used in a given problem should be one calculated at the approximate load on the alternator. If the alternator is connected to the infinite bus, then its terminal voltage remains the same at the bus value. 𝑍𝑠(sat.) =𝐸𝑎𝑐𝐼𝑎𝑏=𝑅𝑎+𝑗𝑋𝑠(sat.)
What is saturation in generator?
Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off.
Why saturated synchronous reactance is less than unsaturated synchronous reactance?
What is saturated and unsaturated impedance?
RE: Saturated or Unsaturated Impedance Generally speaking saturated values are used where the current is high – ie fault calculations. Unsaturated values are used up to rated current ie motor starting calcs.
What is negative sequence reactance of alternator?
Objective:- To determine negative and zero sequence reactances of an alternator. It is the ratio of the fundamental component of armature voltage, due to the fundamental positive sequence component of armature current, to this component of armature current at rated frequency.
What is generator reactance?
The subtransient reactance, X”d, is the generator internal impedance element that is effective in the first cycles of a transient load event and determines the magnitude of the instantaneous fault current from the generator.
What is synchronous reactance of alternator?
Synchronous reactance (Xs): It is the imaginary reactance employed to account for the voltage effects in the armature circuit produced by the actual armature leakage reactance and by the change in the air gap flux caused by the armature reaction.