What is Transformer, basic knowledge, Types and Application.
Transformer is a common electrical equipment, about which we hear and see quite frequently. But, when it comes to answering What is transformer and its basic knowledge like types and application, a common man is made to scratch his head. Well, here I shall be explaining about transformer in laymen term. It is basically an electrical device, which transforms either a low voltage to high voltage or a high voltage to a low voltage. You must be aware that electrical power is generated in power stations (Hydroelectric Power station, Thermal power stations, nuclear power station ). Electric power is generated at low voltage (33kv) due to various limitations in these stations. This power is supplied to consumers over a large area in cities/ town/ village. But, distribution of such low voltage (33 KV ) over such a large area is not feasible. So, in such scenario, the transformer comes handy.
Transformers are installed at various strategic locations. At power stations itself large size transformers are used, to convert low voltage generated into high voltage (66 KV), in order to fetch this high voltage to the main distribution lines. This distribution lines carries this high voltage over a long distance to be supplied to consumers. Again, at the consumer’s end, this high voltage(66 KV) is transformed into low voltage (230 V). For this, the state power Department installs transformers at various location according to the load demand of an area. Note- The electric power coming to your house is of 230 volt.
Some Basic knowledge about Transformer
- Types– There are mainly two types viz, step up transformer and step down transformer. Other types- Distribution transformer and Power Transformer, Instrument transformer, Auto transformers.
- Rating– It is rated in KVA (Kilo Volt Ampere)
- Cost– Depends upon the rating of transformer. It may start at Rs 1.8 lakh.
- Durability and efficiency– They are highly durable and efficient.
- It contains two winding viz, primary and secondary winding. The secondary is generally star connected in order to obtain the earthing wire. Earthing of electrical equipment is essential to protect the working personnel from electrical shock and also to protect the device itself against any fault current.
- It works only with AC (alternating current). It does not work with DC (Direct current). Our houses are supplied with AC.
A simple schematic diagram of a transformer is shown below-
Types of Transformers
- Power Transformer– The transformer that you see in generating stations, big sub-station are the power transformers. Its sole purpose is to convert the low voltage AC power into high voltage AC power at the same frequency. It has high efficiency, higher rating. Before transmitting over long distance to consumers ,every low voltage electric power is stepped up using power transformer .
- Distribution Transformer– These are the transformers you see in your locality. They are installed near the consumers’ load point. Every households in an area is supplied with electrical power of 230 volt using distribution transformers. They have lower efficiency and lower rating compared to power transformer.
- Instrument Transformers– As the name implies these are used as instrument to measure various electrical quantities such as current and voltage. There are mainly two types- (a) Current transformer– to measure current and (b) Potential transformer– to measure voltage.
- Auto transformers– It has slightly different construction than normal transformer. It helps in saving copper material because one of the winding is common to both primary and secondary. It is used as a booster transformer in power system in order to compensate for voltage drops and copper losses in power lines. A brief description about auto transformer has been described below.
Here, as you can see a part of secondary winding is common with primary winding
Here, winding (c-b) is common for both primary and secondary winding. Also. secondary voltage V2 is smaller than the primary voltage V1.
So, from the figure above, we can see that a part of the winding is common to both primary and secondary winding. Because of this fact, there is a saving of copper material in case of auto transformer. This reduces the overall construction cost of auto transformer.
Applications of Transformers-
- Used to rise or lower the voltages while maintaining same frequency
- Act as an isolator. it ca isolate two electrical circuit.
- small transformers, with some modification can be to measure voltage and current.
- It can be used as booster transformer to compensate for voltage drops over transmission lines
Well, I hope with this article you have now, some basic knowledge about a transformer, its types and applications. So, next time don’t think about Optimus Prime when, somebody ask you about a transformer.:) :). Do care to give your feedback in order to improve the article.