Transformer

When the transformer is on load, the secondary winding is connected with load as in figure (1) and current I2 is flowing through load. Operation of Transformer On load Figure (1) shows a transformer with a load connected across the secondary winding. The load current I2 flowing through the secondary turns sets up its own […]

When the transformer is on no-load, the secondary winding is opened as in figure (a) and current I2 is zero. In this condition, the primary winding draws a no-load current ‘I0‘ which has two components i.e., Magnetizing component (Iµ), and Working component (Iw).

Consider the two winding single-phase transformer shown in figure (1).

The Open Circuit and Short Circuit Test on Transformer can be used to determine the efficiency and regulation of a transformer at any predetermined load for that we do not have to actually load the transformer. The parameters of the equivalent circuit of a transformer can be obtained by using the open circuit (O.C.) test

A current transformer (CT) is nothing but a coil wound on a toroidal core. When a large current carried by a conductor is to be measured, it is advisable to avoid the direct connection of ammeter in this high current circuit. For this purpose a current transformer is used. Fig. 1 : Connection of Current

The three phase autotransformer is a combination of three single phase autotransformers. It has three windings, one per phase. Fig. 1 : 3 Phase Autotransformer.

Unlike two winding transformer, an auto-transformer contains only one winding. This single winding serves the purpose of both primary as well as secondary. As this transformer employs only one winding, it uses less copper. Hence it is cheaper and more efficient.

A transformer with tappings on the primary or secondary in order to control the voltage is called as a Tap changing transformer. The tappings are the percentage windings equipped to produce the desired amount of voltage. Tap changers are needed due to the following two reasons. To stabilize the voltage To control the voltage. Tap

Figure 1: Open Delta Connection of Transformer.

Current inrush phenomenon in transformer is the flow of high magnetizing current for short time in primary winding when the transformer is switched ON at the instant when applied voltage is zero.