Xd / Xd`/Xd`` I have drawn a sketch

Status
Not open for further replies.
T

transient

Member
Location
korea
Hello few quick questions ,,but need well elaborated replies ,,I want to learn as to how to design the things .

The motor shown is 10KW (440V 3 phase 0.8 pf) , and uses DOL starter.

Q1) What should be the rating of the generator keeping high starting currents in mind?

Q2) Please explain the terms Xd" Xd' Xd associated with motor and generator.

Q3) How Xd' Xd" Xd will affect the design /rating of the generator choosen.

Q4)So , what should be the type and rating of the breaker should I use ?

Regards
Transient.




generator_and_motor.jpg
 
Xd" is the subtransient reactance and is the reactance used (along with the voltage) to calculate the first few cycles of short circuit current (has some DC offset).
Xd' is the transient reactance and is used to calculate the next several cycles of short circuit current (still has some DC offset, although not as much as the first few cycles).
Xd is used in the calculation of steady state current.

There is also a time constant associated with these values that will tell you how long each of these periods of time actually last.

These values can usually be obtained from the motor manufacturer's test data. These values will definitely be used to choose your breaker size and settings. These values on the generator and motor will also be used to determine the amount of inrush current and how much the voltage will drop on startup. I am not sure if anyone here is willing or able to design your system, but maybe we can offer our opinions on what you can do.

Are these synchronous machines, or induction, or something else?
 
Status
Not open for further replies.
Top