transformer stability test short circuit calculatios.xls

	A	B	C	D
1	TRANSFORMER STABILITY TEST
2	Short Circuit Calculations
3	Transformer Data
4	S =	50	MVA
5	VLow =	13٫8	kV
6	Z =	21٫6	%
7	VAP =	380	V
8	Vhigh =	132	kV	At Center step of tap changer
9
10	IR = S / (√3 * VLow)
11
12	ISC = IR / Z = S / (√3 * VLow * X)
13
14	IINJ = ISC * VAP / VLow = S * VAP / (√3 * VLow2 * Z)
15
16	IR		Rated Current
17	S		Rated Power (ONAN)
18	VLow		Rated Voltage of low voltage side (Injection Side)
19	ISC		Short Circuit Current at Rated Voltage
20	Z		Transformer Percentage Impedance
21	IINJ		The Injected Current at The applied Voltage
22	VAP		Voltage Applied (Test Voltage) at low voltage side
23
24	ILow =	266٫67		A
25	IHigh =	27٫88		A
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