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What are the main reasons why an alternator does not generate electricity?

Electric energy is one of the most important energy sources in modern society. A generator is a mechanical device that converts other forms of energy into electrical energy. It is driven by a water turbine, a steam turbine, a diesel engine or other power machinery, and converts the energy generated by water flow, airflow, fuel combustion or nuclear fission into mechanical energy and transmits it to the generator. Converted to electricity by a generator. Generators are widely used in industrial and agricultural production, national defense, science and technology and daily life. The following editor will introduce to you "what are the main reasons why the alternator does not generate electricity"

What are the main reasons why an alternator does not generate electricity

1. 1. The remanence of the iron core of the generator disappears or is too weak, the newly installed unit is vibrated by long-distance transportation or the generator is placed for too long, the remanence of the iron core of the generator disappears or the residual magnetic induction is weak, causing the remanence voltage of the generator to disappear or less than normal The residual magnetization voltage value, that is, the residual magnetization line voltage is less than 10V, and the residual magnetization phase voltage is less than 6V. Because the stator and rotor of synchronous generator and the stator and rotor iron core of AC exciter are usually made of 1~1.5 mm thick silicon steel sheets, the remanence will easily disappear or weaken when they are vibrated after excitation.
2. 2. The wiring of the excitation circuit is wrong. When the generator is repaired, the polarity of the excitation winding is accidentally connected in reverse. After the power is turned on, the magnetic field generated by the current of the excitation winding is counteracted with the direction of the remanence, resulting in the disappearance of the remanence. In addition, when overhauling, measuring the DC resistance of the excitation winding or testing the automatic voltage regulator AVR to pass the DC current to the excitation winding, without paying attention to its polarity, the remanence of the iron core will also disappear.
3. 3. The circuit of the excitation circuit is blocked, the electrical contact in the excitation circuit of the generator is poor or the terminals of each electrical component are loose, the lead wire is disconnected, causing the circuit to be interrupted, and the excitation winding of the alternator has no excitation current.
4. 4. The circuit on the DC side of the rotary rectifier is interrupted. Because the circuit on the DC side of the rotating rectifier is interrupted, after the exciter is rectified by the rotating rectifier, the excitation current provided to the excitation winding cannot be fed into the excitation winding, resulting in the failure of the AC synchronous generator to generate electricity.
5. 5. The AC exciter has no output voltage due to failure. The AC exciter fails to generate voltage, so that the excitation winding of the AC synchronous generator has no excitation current.
6. 6. The generator excitation winding is disconnected or grounded. Cause the generator to have no excitation current or a very small excitation current.