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Transformer Losses & Efficiency Calcualation
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:Three Phase Transformer Detail: NAME PLATE
:I²R Losses Calculation:
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Transformer MakeDemo Transformer HV Full load current :0.87Amps
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Transformer Serial NoTipsENGINEER/001LV Full load current :20.87Amps
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KVA rating of Transformer15000VAHV Side I2R losses 237.389Watts
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Primary voltage 10000VoltsLV Side I²R losses 143.72Watts
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Secondary voltage415VoltsTotal I² R lossses @ Amb temp381.10Watts
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Primary side ConnectionDELTATotal Stray losses @ Amb temp 13.90Watts
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Scondary side ConnectionSTARI² R lossses @75° c temp 445.82Watts
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No load losses71WattsStray losses @ 75° c temp 11.88Watts
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No load current0.6AmpsTotal Full load losses at @75° c 457.70Watts
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Full load losses395WattsTotal Impedance at ambient temp 869.95Ohms
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Impedance voltage435VoltsTotal Resistance at amb temp 508.11Ohms
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Lv resistance in milli ohms220m OhmsTotal Reactance (X) : 706.14Ohms
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Hv resistance in ohms 211OhmsResistance at@ 75° c594.39Ohms
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Amb temperature 30Deg c Impedance at 75° c 923.00Ohms
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Total Connected Load on Transformer
9000VAPercentage Impedance 4.62%
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% Loading of Transformer60%Percentage Resistance 2.97%
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Percentage Reactance 3.53%
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Tips Engineer Zone
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www.tipsengineerzone.in
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https://www.tipsengineerzone.in/2020/12/transformer-design-online-course-for.html
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https://tipsengineerzone.myinstamojo.com/
:Efficiency Calculation:
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Efficiency at P.F of Unity
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EMAIL ID - tipsandtricksengineerzone@gmail.com
At Transformer Loading 125%96.57%
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Visit Website : www.tipsengineerzone.in
At Transformer Loading 100%97.07%
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MOBILE - 9798760634At Transformer Loading 75%97.53%
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ADDRESS - GurgaonAt Transformer Loading 50%97.83%
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At Transformer Loading 25%97.53%
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Efficiency at P.F of 0.8
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At Transformer Loading 125%99.49%
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At Transformer Loading 100%96.37%
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At Transformer Loading 75%96.93%
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At Transformer Loading 50%97.30%
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At Transformer Loading 25%96.94%
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FormulasRemarks
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HV Full load current = VA / (1.732xVolt)VL - LINE VOLTAGE
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LV Full load current = VA / (1.732xVolt)
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HV Side I2R losses = I²R x1.5IL - LINE CURRENT , Resistance Ph- Ph
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LV Side I²R losses = I²R x0.5x3IL - LINE CURRENT , Resistance Ph- Ph
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Total I² R lossses @ Amb temp = Hv losses+ Lv losses
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Total Stray losses @ Amb temp =Measured losses -I² R losses
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I² R lossses @75° c temp = ((235+75) x losses) / (225+ Amb temp)Copper
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Stray losses @ 75° c temp=((235+Amb temp)(Stray losses at amb)) / 310
RT=R0(235+T)/(235+Amb Temp)
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Total Full load losses at @75° c = I²R losses at 75°c+Stray losses at 75°c
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Total Impedance at ambient temp =(Imp voltage x1.732) / Full load current
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Total Resistance at amb temp = I²R losses / I²
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Total Reactance (X) =SQRT(Impedance ²- Resitance ²)
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Resistance at@ 75° c =(310 x resistance at amb ) /(235+Amb temp)
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Impedance at 75° c =SQRT(R² at 75 + X²)
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Percentage Impedance =(Z at 75° c x I x 100)/V1
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Percentage Resistance =( R 75° c x I x 100)/V1
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Percentage Reactance =(X x I x 100) / V1
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Efficiency at Unity P.F
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At 125 % of Transformer Loading =(Kva x 1.25 x 100)/((kva x 1.25)+(I²R losses x 1.25²)+(No Load Losses))
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Efficiency at 0.8 P.F
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At 125 % of Transformer Loading =(Kva x 1.25xp.f x 100)/((kva xp.fx 1.25)+(I²R losses x 1.25²)+(No Load Losses))
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