A generator is connected to a transformer which feeds another transformer through a short feeder.

The zero sequence impendance values are expressed in p.u. on a common base and are indicated in figure.The Thevenin equivalent zero sequence impendance at point B (in p.u.) is

Q. A generator is connected to a transformer which feeds another transformer through a short feeder. The zero-sequence impedance values are expressed in p.u. on a common base and are indicated in figure below



The Thevenin's equivalent of zero sequence impedance at P is

Q. The positive , negative and zero sequence impedance of $3-\varphi$ generator are 0.4 pu, 0.3 pu and 0.2 pu respectively. For a line to line fault with fault impedance $Z_f$ and fault current is $I_{f1}=0.2I_f$, where $I_f$ is the fault current with zero fault impedance, then value of $Z_f$ will be ___ pu.

Q. A transmission line has 0.1 pu impedance on a base of 132 kV, 100 MVA. The pu impedance on a base of 220 kV, 50 MVA is ____pu.

Q. The series impedance matrix of a short $3-\varphi$ transmission line in phase coordinates is represented by Z,

$where,Z=\left[\begin{array}{ccc}{Z}_s& Z_m& Z_m\\ Z_m& Z_s& Z_m\\ Z_m& Z_m& Z_s\end{array}\right]$

If the positive sequence impedance is $(4+j16)\Omega$ and zero sequence impedance is $(8+j32)\Omega$, then value of imaginary of $Z_m$ is ________$\Omega$

Q. Two identical unloaded generators are connected in parallel as shown below



Both the generators are having positive, negative and zero sequence impedances of 0.6 p.u., 0.4 p.u. and j0.35 p.u. respectively. If prefault voltage is 1 p.u., for a line to ground (L-G) fault at the terminals of the generator, the fault current magnitude in p.u. is______.
(Assume neutral impedance $Z_n=j0.02p.u.)$