Rf3 - Calculations of current for setting of ICT backup relay Highset Element

     At a 220/132kV Sub-Station there are two ICTs operating in parallel. ICT-I having capacity of 200 MVA. Whereas the capacity of ICT-II is 100 MVA.



     HV and IV Bus fault levels and contribution of fault current by each ICT for HV and IV bus fault is as shown in the following table

     Calculate HV and IV CT Primary Currents for fault at respective side LA
**FOR ICT-??**.

Bus Fault Levels MVA
Bus	Fault Type	Fault Level in MVA
ICT HV Bus	3-Phase (LLL)	??
	1-Phase (SLG)	??
ICT IV Bus	3-Phase (LLL)	??
	1-Phase (SLG)	??

Fault Current contribution by ICTs
Fault At	Type	ICT	Winding	Ampere
ICT HV Bus Fault	3-Phase (LLL)	ICT-I	HV Winding	??
			IV Winding	??
		ICT-II	HV Winding	??
			IV Winding	??
	1-Phase (SLG)	ICT-I	HV Winding	??
			IV Winding	??
		ICT-II	HV Winding	??
			IV Winding	??
ICT IV Bus Fault	3-Phase (LLL)	ICT-I	HV Winding	??
			IV Winding	??
		ICT-II	HV Winding	??
			IV Winding	??
	1-Phase (SLG)	ICT-I	HV Winding	??
			IV Winding	??
		ICT-II	HV Winding	??
			IV Winding	??

(NOTE: Relay current corresponding to 70% of these calculated current values to be used for setting of ICT Backup Relay HS element. )

1.a) HV Side LA 3-Ph fault current =    Amp.

1.b) Current contribution by ICT for above fault =    Amp.

1.c) Current contribution from HV Bus for above fault =    Amp.

2.a) HV Side LA 1-Ph fault current =    Amp.

2.b) Current contribution by ICT for above fault =    Amp.

2.c) Current contribution from HV Bus for above fault =    Amp.

3.a) IV Side LA 3-Ph fault current =    Amp.

3.b) Current contribution by ICT for above fault =    Amp.

3.c) Current contribution from IV Bus for above fault =    Amp.

SNa) IV Side LA 1-Ph fault current =    Amp.

SNb) Current contribution by ICT for above fault =    Amp.

SNc) Current contribution from IV Bus for above fault =    Amp.

Topic SETICTBU Ex-3 Your score is:

000

Select Zone:

Select Unit:

Code Number:

ABD AMT NSK PUN NGP KRD VSH

ABD1 ABD2 JALN PRBN NND1 NND2 LTR1 LTR2 BEED PRLI EKTN GRWL WALJ TPTN KMBH