Find out the magnitude of sag votage vsag assuming there is

Question

Topic: power quality

1) For the following tow sub-transmission system, find out the magnitude of sag voltage, V_sag, assuming there is no load current and the source voltage has a value of 1 pu.

2) For the folllwing non-radial system, find out the magnitude of sag votage, V_sag assuming there is no load current and the public supply as well as the local generator prdices a votlage of 1 pu.