A transformer is a static machine utilized for transforming power from a circuit to another without changing frequency. It is a standard concise explanation of transformer. Since there is no rotating or moving part so transformer can be a static device. Transformer operates on ac supply. Transformer works on the principle of mutual induction.
If we would like to understand the background of transformer we have return long in the 1880s. Around half a century before that in 1830 property of induction the working principle of transformer was discovered. Later the transformer design was improved resulting in more efficiency and lesser size. Gradually the large capacity of electrical transformers in all the different several KVA, MVA came into existence. In the year 1950, 400KV electrical power transformer was introduced in high voltage electrical power system. In the early 1970s, unit rating the size of 1100 MVA was produced and 800KV and even higher KV class transformers were made in year of 1980.
Generation of electrical power in low voltage level is quite much economical. Theoretically, this low voltage level power can be transmitted on the receiving end. This low voltage power if transmitted brings about greater line current which indeed causes more line lossesBut in the event the voltage measure of an electric power is increased, the current from the power is reduced that causes reduction in ohmic or I2R losses within the system, lowering of cross sectional part of the conductor i.e. decline in capital price of the machine and it likewise raises the voltage regulating the device. As a consequence of these, low level power needs to be stepped up for efficient electrical power transmission. This is accomplished by boost transformer at the sending side of the power system network. Because this high voltage power may not be given to the consumers directly, this needs to be stepped as a result of the desired level with the receiving end with the help of step down transformer. Electrical power transformer thus plays an important role in power transmission. power system Two winding transformers are often used where ratio of high voltage and low voltage is in excess of 2. It can be economical to make use of auto transformer where the ratio between high voltage dexjpky57 low voltage is lower than 2. Again a single unit three phase transformer is a lot more economical compared to a bank of three 500kv power transformer within a three phase system. But a single three phase transformer unit is a little hard to transport and must be taken off service entirely if among the phase winding stops working.
Forms of Transformer
Transformers could be categorized in different ways, based upon their purpose, use, construction etc. The kinds of transformer are listed below,
Step-up Transformer and Step Down Transformer – Generally used for stepping down and up the voltage degree of power in transmission and distribution power system network.
Three Phase Transformer and Single Phase Transformer – Former is generally used in three phase power system as it is cost-effective than later. But when size matters, it is actually preferable to utilize a bank of three single phase transformer as it is easier to transport than one single three phase transformer unit.
Electrical Power Transformer, Distribution Transformer and Instrument Transformer – Power transformers are often utilized in transmission network for stepping up or down the voltage level. It operates mainly during high or peak loads and it has maximum efficiency at or near full load. Distribution transformer steps on the voltage for distribution purpose to domestic or commercial users. It offers good voltage regulation and operates 24 hrs every day with maximum efficiency at 50% of full load. Instrument transformers include C.T and P.T which are used to reduce high voltages and current to lesser values which is often measured by conventional instruments.
Two Winding Transformer and Auto Transformer – Former is normally used where ratio between high voltage and low voltage is more than 2. It is actually affordable to utilize later where the ratio between high voltage and low voltage is under 2.
Outdoor Transformer and Indoor Transformer – Transformers that are designed for installing at outdoor are outdoor transformers and transformers intended for installing at indoor are furnace transformer.
Oil Cooled and Dry Type Transformer – In oil cooled transformer the cooling medium is transformer oil whereas the dry type transformer is air cooled.
Core type, Shell type and Berry type transformer – In core type transformer it provides two vertical legs or limbs with two horizontal sections named yoke. Core is rectangular fit by using a common magnetic circuit. Cylindrical coils (HV and LV) are positioned for both the limbs.
Shell type transformer: It has a central limb as well as two outer limbs. Both HV, LV coils are positioned about the central limb. Double magnetic circuit is present.
Berry type transformer: The core looks like spokes of wheels. Tightly fitted metal sheet tanks can be used as housing this kind of transformer with transformer oil filled inside.