Q$1$: $($please handwrite$)$

A single line diagram of a power system is shown in the figure below. The $3$ sequence network reactances for the various components are as given below and they are in per unit on a common MVA base.

$1-$ Draw the positive and negative and zero sequence networks.

$2-$ Find the Thevinen equivalent reactance for $+$ve $,-$ve $,$ and zero sequence networks as viewed from:

MMM$=847$ So solve bus $2$

Bus $1$ if the last three digits from right of your registration number is between $000$ and $199.$

Bus $2$ if the last three digits from right of your registration number is between $600$ and $999.$

Bus $3$ if the last three digits from right of your registration number is between $200$ and $599.$

$3-,$ Find fault currents supplied by generator $1,$ generator $2,$ generator $3,$ and generator $4$ sides for a single line to ground fault occurred on phase $($a$)$ at

Bus $1$ if the last three digits from right of your registration number is between $000$ and $199.$

Bus $2$ if the last three digits from right of your registration number is between $600$ and $999.$

Bus $3$ if the last three digits from right of your registration number is between $200$ and $599.$

For the generators $($G$1,$ G$2,$ G$3,$ G$4)$ assume $x1=x2=j0\mathrm{.}18$;$x0=j0\mathrm{.}080pu$

MMM$=847$

For Transformers $($T$1,$ T$2,$ T$3,$T$4)$ assume $x1=x2=x0=j(0\mathrm{.}06+MM\frac{M}{10000})$ pu where MMM is the last three digits $($from right$)$ of your registration number.

For Transmission lines $($TL$1,$TL$2)$ assume $x1=x2=j0\mathrm{.}24$;$x0=j0\mathrm{.}48pu,$ whereas

#MMM$=847$

For Transmission line $($TL$3)$ assume $x1=x2=j(0\mathrm{.}14+MM\frac{M}{10000}),x0=j(0\mathrm{.}42+MM\frac{M}{10000}),$

$4-$ Compare this value of fault current for this type of fault with the fault current passes if a three phase symmetrical fault occurs at the same bus$>$

$5-$ If the side of the transformer $3($T$3)$ which nearer to the generator $3($G$3)$ is delta connected instead of star connected. Does the fault current remains the same or changes. Verify your answer.

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