There are two types of connections in three phase system, Star and Delta connections. Each will be discussed briefly and in easy words.
Three phase connections Star and Delta Connections
Star Connection ( Three phase Four wire system)
Star connection has Three phases and has one common neutral line therefore, star connection is used for long distance transmission. Now the main we discuss is balanced and unbalanced current. If the all phases have same current it is called balanced current and when current is not balanced in all phases it is said to be unbalanced current.
Unbalanced current may damage the transformer, the neutral line is used to protect the transformer and provide the short path towards ground to the unbalanced current.
when the current is balanced in all phases then there is no current in neutral line.
There is some terms used in the star connection 3 phase.
Line voltage
The voltage that is measured between two phases in three phase system is called Line Voltage.
Phase Voltage
The voltage that is measured between one phase line and the neutral line is known as phase current.
Note: Current will be same in line and phase voltage.
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Delta Connection (Three phase Three wire system)
There is major difference between delta and star connection. Delta connection has no neutral line, when load is attached with the delta connection in base station, ground can be used as neutral line. This connection carry unbalance current therefore it is used for short distance transmission.
In delta connection line voltage and phase voltage is same. The line current is √3 times of phase current.
Delta and star connection both are power independent. The total power (net power) will be same in both arrangement.
The power can be calculated as
PF (Power factor) is most important in three phase system if found some value of PF, must be corrected by engineers and technicians. PF can be adjusted be using capacitors.