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What are the reasons of the voltage drop in the secondary of the transformer?
Loading the secondary winding with a simple load impedance causes a secondary current to flow, at any power factor, through the internal winding of the transformer. Thus voltage drops due to the windings internal resistance and its leakage reactance causes the output terminal voltage to change.
What determines the change in voltage between the primary and secondary winding of a transformer?
The ratio between the number of actual turns of wire in each coil is the key in determining the type of transformer and what the output voltage will be. A transformers output voltage is greater than the input voltage if the secondary winding has more turns of wire than the primary winding.
Is the percentage impedance of a transformer same on primary and on secondary?
The value of percentage impedance is the same for both windings as it is the percentage of rated voltage. However, the value of the rated current will be different for primary and secondary windings. Accordingly, value of short circuit current will also be different for primary and secondary windings.
How do you calculate the fault current of a transformer?
You can determine the Full Load Amps of a transformer with the following formula: FLA = VA / L-L Voltage x 1.732, so using the example above we get FLA = 1000000 / 480 x 1.732 or 1000000 / 831.36 = 1202.84 (note the conversion from kVA to VA, 1000 x 1000 = 1000000).
What causes voltage drop on the secondary side of a transformer?
The current drawn on the secondary side is ‘provided’ by the primary side. This current on the primary side causes a voltage drop in R1, reducing the voltage V1 at the primary side of the transformer. The secondary voltage changes proportionally (to the transformer ratio) with the reduced voltage V1.
When does a load flow through a transformer?
Whenever a load is connected to the secondary winding, load current will start to flow through the load as well as secondary winding. This load current solely depends upon the characteristics of the load and also upon the secondary voltage of the transformer.
How is the current passing between Transformers determined?
The current passing between the primary and secondaries of all the transformers in a chain is determined by the turns ratios of all the transformers. The loss factors have no significant effect on these current values, just the voltages. And how would a non-unity power factor affect this?
How to calculate voltage drop in single phase transformer?
Formula. Single Phase Transformer: Vd = I (R cos theta + X sin theta) Three Phase Transformer: Vd = sqrt (3) x I (R cos theta + X theta) where: Vd = voltage drop. R = Resistance. X = Reactance. theta = power factor angle.