Generator faults can be considered under the following heads: 1. Stator Winding Faults 2. Field Winding or Rotor Circuit Faults 3. Abnormal Operating Conditions. 1. Stator Winding Faults: Such faults occur mainly due to the insulation failure of the stator coils. The main types of stator winding faults are: (i) Phase-to-earth faults (ii) Phase-to-phase faults and (iii) Inter-turn faults involving [...]
In this article we will discuss about:- 1. Stator Protection of Generators 2. Overload or Overcurrent Protection of Generators 3. Over-Voltage Protection 4. Over-Speed Protection 5. Protection against Motoring 6. Negative Sequence Protection 7. Protection against Vibration 8. Bearing Overheating Protection 9. External Fault Backup Protection 10. Direct Connected Protection. Stator Protection of Generators: The earth fault current is usually [...]
The following points highlight the top seven systems employed for stator protection of generators. The systems are: 1. Differential Protection for Generators 2. Modified Differential Protection for Generators 3. Biased Circulating Current Protection (Percentage Differential Relay Protection) 4. Self-Balance Protection System 5. Balanced Earth-Fault Protection 6. Stator Inter-Turn Protection 7. Stator Overheating Protection. System # 1. Differential Protection for Generators: [...]
The different protection schemes for rotor protection of generators are described as follows: 1. Rotor Earth Fault Protection 2. Loss of Excitation (or Field Failure) Protection 3. Protection against Rotor Over-Heating Because of Over-Excitation 4. Rotor Temperature Alarm 5. Automatic Field Suppression and Use of Neutral Circuit Breaker. Scheme # 1. Rotor Earth Fault Protection: Field circuits are operated unearthed [...]
The synchronous generators may be classified as: 1. Hydroelectric Generators 2. Turbo Alternators 3. Diesel-Engine Driven Synchronous Generators. 1. Hydroelectric Generators: The generators employed in hydroelectric power plants are three phase alternating current synchronous generators, called the alternators. Alternator consists essentially of two parts namely armature and field magnet system. The armature of an alternator is an iron ring, formed [...]