Hello friends, today I am going to tell you Types of Faults in Alternator, Faults in Alternator: If you also want to know, then keep reading this article completely.
Types of Faults in Alternator
There are many types of defects in an alternator. These defects are as follows.
Stator Fault
These come in the stator of the alternator. These come due to a fault in the insulator in the tricycle armature coil. These are three types.
What can cause severe damage to the machine?
(a) Phase to Earth Fault – This Pradosh comes in the armature tool. If the faulting current is less than 20A, the machine rapidly trips and is saved from burning. If the faulty current is more than 20A, there is a high possibility of burning the stator. Due to this, the entire lamination has to be changed, which is very costly and takes a lot of time.
(b) Phase to Phase Fault – This occurs due to the short path between two windings. It is less likely to come because large insulators are placed between the coils. But once earth f comes faults from the art, it generates excessive heat due to which these faults can come. Due to this Pradosh, severe arcing occurs with high temperatures, and the generator catches fire.
(c) Stator Inter-turn Faults – In this, the coil used in the alternator has many turns. The Pradoshas, which occur in the turns of a winding, are called internal Varta Pradoshas. These faults occur when the voltage of a high value (L di/dt) is brought due to the opposite currents of the current. They are less likely to appear in a single circle winding.
Rotor Faults
The rotor of this alternator is made up of field winding. There are many turns in the field winding. Conductor to earth faults and short circuit faults occur between the turns of the field winding. These are the mechanical and thermal pressures that come in the field winding insulator.
- Read more: What is a Static Relay: Advantages, Uses
Abnormal Running Conditions
In the following unusual circumstances, the alternator may be defective. The following are the circumstances.
- Prime Mover Failure Fault
- field failure
- overcurrent or overload
- load imbalance
- blocking failure
Some of these faults are described as follows- Types of Faults in Alternator.
1. Prime Mover Fault- Generally, several alternators are run in parallel to each other to generate electric power. If the prime mover of any of these alternators is turned off for any reason, it starts functioning as a motor. Still, it keeps itself synchronized, and the alternator becomes operational again. Therefore, protection is not required for this type of fault. Still, if such a fault occurs in the prime mover, the alternator starts taking higher current than the other alternator in the form of motor, then again power protection method is used.
2. Field failure- The probability of failure of the alternator’s field is significantly less. But it depends on the load and the condition of the machine. The machine is turned off by using an internal current relay in the field circuit. If the alternator’s field fails, there is no possibility of damage for some time, so the working protection itself is not needed to turn off the alternator.
3. Overcurrent/Overload – Usually, the (reaction) reactance of the alternator is kept high enough that it does not pose any danger to overload. Therefore usually, the alternator does not need to be overloaded. Overcurrent relays are used for overload protection of the alternator.
4. Unbalance of load – The imbalance of load on the alternator usually occurs due to ground fault or fault in the external circuit of the alternator between phases and this imbalance: If less than the rated current of the alternator, the excessive heating effect occurs in the rotor. Damages the insulation of the rotor or the mechanical stability of the rotor.
5. Insulation Safety- Failure of the resistor (insulation) of the alternator is the most dangerous fault of the alternator. If the insulation of the alternator fails, the fault is fed by the alternator itself and by the other alternator, causing the machine to fail. The resistor usually gets damaged due to the following reasons
(a) phase to phase defect
(b) earth faults from the phase
(c) turn to turn faults on the same phase winding
- Read more- Types of Electrical Insulator
Percentage Differential Protection
This method is also called Biased Differential Protection or Merz Price Protection. Types of Faults in Alternator-
This protection represents the vector difference between two or more equal electrical quantities. A current alternator is installed at each end of the armature winding to protect the alternator.
For through faults and when there is no fault in the winding, the current value in the pilot wire through the contacts in the current transformer remains the same, i.e., the differential current ( I1 – I2) is zero.
But when a fault occurs in the protection winding, the balance is disturbed, and the differential current (I1 – I2) starts flowing through the operating coil of the relay, due to which the relay operates. The circuit breaker of the generator falls. (Trip) yes It is.
Differential Protection Scheme protects against defects in windings, such as Kala to Kala and Kala to Earth defects.
It is not enough to isolate the generator by simply tripping the circuit breaker to prevent damage to the generator in case of stator faults. The prime mover of the generator keeps rotating, causing E.M.F. in the stator winding. Arises and faults current starts flowing. To stop this current, the interlocking of the current is done with the current breaker. When the circuit breaker operates the field winding, then that field winding becomes an open circuit.
Percentage (%) Differential relay first starts the auxiliary relay, which disconnects the main circuit breaker and the field circuit breaker, which stops the prime mover’s rotation and starts the alarm.
- Read more: What is Protective Relay?
what did you learn today:-
Friends, today you learned Types of Faults in Alternator, how to fix a fault alternator,how to check a faulty alternator, which are faults in alternator, how to detect a faulty alternator,what are the rotor faults in alternator, stator faults in alternator, types of alternator protection, alternator protection wikipedia, field suppression of an alternator, how to know a faulty alternator, different types of faults in alternator, what are the different types of alternators.. If you liked the information given by me, then you can share it with your friends and if you have any question or suggestion in your mind, then you can tell by commenting below.