A generator is an electrical machine that converts mechanical energy into electrical energy.
Generators are generally classified as below:
Synchronous generator Vs. Induction generator
The difference between Synchronous generator and Induction generator is as mentioned below:
1) Synchronous generator
- The field is excited by an external D.C excitation and the rotor is connected to prime mover.
- The synchronous generator always operates at synchronous speed (Ns).
- Since, the field is excited by an external D.C source, the synchronous generator can deliver both the real/true and reactive power.
- Real power is being supplied by prime mover input and reactive power is supplied by external D.C excitation connected to the field.
- Hence, both real and reactive supplied can be controlled.
- Since, the reactive power can be fully controlled, the synchronous generator can be operated at all range of power factors (Lagging, Leading, Unity power factor).
- Efficiency is good.
- Suitable for conventional power station i.e thermal, nuclear, gas, hydro and diesel power stations.
- Most of the power generation (nearly 80%) is by conventional power stations employing synchronous generator.
2) Asynchronous generator
- Since induction generator is connected to the power system, the field is excited by the reactive power taken from the grid and the rotor is connected to prime mover.
- The induction generator always rotates at more than synchronous speed (Nr>Ns).
- Since, the field is excited by the power system, the synchronous generator can deliver only real/true power but absorbs the reactive power.
- Real power is being supplied by prime mover input and reactive power is absorbed from the system.
- Since, the prime mover, in case of induction generator operates at variable speed. Hence, both real and reactive power cannot be controlled.
- Since, the reactive power is being absorbed from power system, the induction generator operates only at leading power factor.
- Efficiency is poor.
- Suitable for windmills, tidal power stations etc.
- Altogether, very less power is generated using induction generator.
I hope you have got some good and relevant information from this blog.
Feel free to ask any doubt/query in the comment section or you can contact us through mail.
Comments
Post a Comment