Why the equivalent circuit can be simplified into approximate equivalent circuit?

In fact, an equivalent circuit of any electric instrument is important for the analysis of its performance and to discover any scope of further modification of modeling. The equivalent circuit of transformer includes a setup of inductance, resistance, voltage, capacitance, etc.

Why is equivalent circuit of transformer needed?

The equivalent circuit diagram of a transformer is a simplified circuit in which the impedance, resistance and leakage reactance of the transformer can be more easily calculated. The equivalent impedance of transformer is an important parameter to be calculated.

How do you obtain the approximate equivalent circuit of a transformer as referred to the primary?

R2′ = K2R2 and X2′ = K2X2 . The following figure shows the equivalent circuit of transformer with secondary parameters referred to the primary. Now, as the values of winding resistance and leakage reactance are so small that, V1 and E1 can be assumed to be equal.

What is the equivalent circuit of an ideal transformer?

An ideal transformer is a transformer without losses. For an ideal transformer, the secondary load can be represented as an equivalent circuit seen from the primary side (fig. 16-7b), as long as: R’ = k2. Rs ; L’ = k2.

What is the significance of equivalent circuit?

Equivalent Circuit. Equivalent circuits are used in order to approximate the experimental impedance data with the above-mentioned ideal or distributed impedance elements, both arranged in series and/or in parallel. Many electrochemical systems have been analyzed according to this procedure.

What is the advantage of obtaining the equivalent circuit of a single phase transformer?

From the equivalent circuit , we can easily calculate the total impedance of to transfer voltage, current, and impedance either to the primary or the secondary.

Which of the following losses varies with the load in the transformer?

Explanation: As we know, the transformer has primarily two types of losses Iron loss and copper loss. Iron loss is always constant, whereas copper losses are varying with a load. Both hysteresis loss and eddy current loss do not depend upon load current, which means iron losses are constant with varying load.

Why the OC test is normally done on the LV side?

Why OC test is performed on LV side? Explanation: Open circuit test can be performed on any side but for our convenience and supply voltage available we generally conduct the test on LV side, to get corresponding parameters on HV side we can use transformation ratio. Current by voltage will give net admittance. 6.

Why is the transformer rated in kVA?

Now, In second scenario, connect a capacitive or inductive load to the secondary of the transformer at power factor θ = 0.6. Hence proved that losses in both primary and secondary are the same. P = 220 x 50 x 0.6 = 6.6kW. kVA = 220 x 50 / 1000 = 11kVA.

Why will a transformer work only from an alternating supply?

transformer work only on ac supply because A transformer needs an alternating current that will create a changing magnetic field. A changing magnetic field also induces a changing voltage in a coil. This is the basis of how a transformer works: The primary coil is connected to an AC supply.

What is the primary current of a transformer on no load?

We know that, when the transformer is on no load, the no load current or primary current is very small, typically 3 to 5 percent of the rated current value. Thus, the copper loss in the primary winding is negligible.

How to predict the performance of a transformer?

It is possible to predict the performance of a transformer at various levels of load by knowing all the equivalent circuit parameters. These circuit parameters are supplied in terms Open Circuit (OC) and Short Circuit (SC) test data of a transformer.

Why the no load shunt branch is absent in equivalent circuit?

In other words, the voltage applied to the primary winding is very low, thereby the flux level in the core is very small. In turn there is negligible core loss. Therefore, the no load shunt branch is considered as absent in equivalent circuit of this test as core loss is negligible.

What is the difference between primary and secondary voltage of transformer?

The no-load voltage(referred to the primary) of the transformer is the primary voltage. As the load increases to full load, current flows in the windings of the transformer and there is a voltage drop across the transformer, and the referred value of the secondary voltage is no longer equal to the primary voltage.