Question $1$

$($a$)$ A power system as shown in Figure Q$1$ has a maximum fault level $2000$MVA at $33$ kV $.$ There are two other generating sources connecting to the $6\mathrm{.}6$ kV busbar. If there is a three$-$phase balanced fault at the $6\mathrm{.}6$ kV outgoing circuit, determine the fault level in MVA and the fault current in kA$.($Use $100$MVA as base MVA.$)$

$(12$ marks$)$

$($b$)$ The circuit breaker rating at outgoing circuit is $150$ kA $,$ what could happen when the $3-$phase fault occurred?

$($c$)$ Suggest TWO methods with explanation to reduce the fault level in part $($b$).(5$ marks$)(8$ marks$)($Total: $25$ marks$)$

$2000$MVA $($fault or source level$)$

Figure Q$1$