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220/2200 V transformer test parameters

Short answer

From no-load test: Ro=484 Ω, Xo=198.1 Ω. Short-circuit parameters referred to primary: R01=0.0469 Ω, X01=0.129 Ω.

The no-load test and short circuit test on a 220 V/2200 volt single phase transformer gave following results. No load test (on L.V side): 220 V, 1.2 Amp, 100 watts Short circuit test (on HV side): 110 V, 8 Amp, 300 watts Calculate equivalent circuit parameters refer to primary side and draw the equivalent circuit.

Given: 220/2200 V. No-load (LV side): 220 V, 1.2 A, 100 W. SC (HV side): 110 V, 8 A, 300 W. Primary = LV side (220 V); K = 2200/220 = 10.

Shunt branch (already on primary)

cos φ0 = 100/(220 × 1.2) = 0.3788
Iw = 1.2 × 0.3788 = 0.4545 A
Iμ = √(1.2² − 0.4545²) = 1.1106 A
Ro = 220/0.4545 = 484 Ω
Xo = 220/1.1106 = 198.1 Ω

Series branch

On the HV side: Z02 = 110/8 = 13.75 Ω; R02 = 300/8² = 4.6875 Ω; X02 = √(13.75² − 4.6875²) = 12.93 Ω.

Referred to the primary (÷ 100):

Z01 = 0.1375 Ω ;  R01 = 0.0469 Ω ;  X01 = 0.1293 Ω

Equivalent circuit (primary = 220 V side)

        R01=0.0469Ω  X01=0.1293Ω
 o──┬────┬────/\/\/──────(((───────o
    │    │                          
  484Ω  198.1Ω                  load
    │    │                       V2'
 o──┴────┴───────────────────────────o

Answer: Ro = 484 Ω, Xo = 198.1 Ω, R01 = 0.0469 Ω, X01 = 0.129 Ω.

✓ Answer checked by Claude Opus 5.5 (high effort)

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