What is the reason why a three-phase alternator are normally Wye connected?

Alternators are connected primarily in star to achieve the following motives: Lesser stress on insulation and Copper saving: Voltage per phase is less for a given line voltage which reduces insulation requirement and this also reduces the number of turns hence copper is also saved.

Why the armature winding is always connected in star?

But in the case of Delta connection, the windings of the alternator always in the closed circuit even when the alternator is not connected to any load. So a circulating current always flows through the winding which causes heat. These are the important reasons Why Alternator Armature Winding always connected in STAR.

How does a three-phase alternator work?

Three-phase alternators have three sets of windings; they’re more efficient than a single-phase alternator, which produce a single-phase AC current. When working properly, the three windings produce three currents that make up the three phases. Adding all three together produces the total AC output of the stator.

How are most three-phase generators connected?

3 phase generator connection types The generator coils can be connected in a Delta connection or a star (Y) connection. A Delta (Δ) connection is formed by connecting the end of each coil to the start of another. It must be noted that the star connection is most commonly used for stator coils.

Which is better delta or wye connection?

An advantage of the Delta connection is higher reliability. If one of the three primary windings fails, the secondary will still produce full voltage on all three phases. An advantage of the Wye connection is that it can provide multiple voltages without the need for additional transformers.

Why is the armature winding of alternator always placed on stator Mcq?

Why Rotating Magnetic field: Like dc machine armature of the machine can be placed on the rotor and still we can operate the synchronous machine. Therefore for large rating machines (500kVA to 750MVA) armature is placed on the stator which requires no brushes to collect the large currents.

What is Delta connected load?

Fig.1: Delta Connected Load. An advantage of a delta connected load over a Y-connected load is that loads may be added or removed readily on a single phase of a delta since the loads are connected directly across the lines.

What are the two main types of three-phase connections?

The two main types of three-phase Connections are Delta and Wye or Star connection. The Wye or Star connection is made by connecting one end of each of the three-phase together as shown in the Figure 1.

How many phase voltages are in a 3 phase alternator?

In a three-phase, Y-connected alternator, the total voltage, or line voltage, across any two of the three line leads is the vector sum of the individual phase voltages. Each line voltage is 1.73 times one of the phase voltages.

What is a wye connection on an alternator?

Rather than having six leads coming out of the three-phase alternator, the same leads from each phase may be connected together to form a wye (Y) connection, as shown in Figure 1, view B. It is called a wye connection because, without the neutral, the windings appear as the letter Y, in this case sideways or upside down.

What is the output frequency of alternator voltage?

The output frequency of alternator voltage depends upon the speed of rotation of the rotor and the number of poles. The faster the speed, the higher the frequency. The lower the speed, the lower the frequency. The more poles there are on the rotor, the higher the frequency is for a given speed.

Which alternators are eharing an inductive load equally?

(YouTube, Vimeo, Vine, Instagram, DailyMotion or Youku) ⇒ Two alternators ‘1’ and ‘2’ are eharing an inductive load equally. If the excitation of alternator ‘1’ is increased