Advantages and Disadvantages of AC Generator

Electricity is a crucial part of modern lives, and hence when it comes to the generation of electricity, all big and small units rely on generators. A generator is a device that converts mechanical energy into electrical energy by generating alternating current. It can be of two types: AC generators and DC generators. An AC generator is a machine that converts mechanical energy into electrical energy to generate current. Steam, water, or nuclear energy can drive the mechanical energy required for electricity generation.

AC generators differ from DC generators by generating alternating current using the slip ring mechanism. These are used in different daily applications like sailboats, microwaves, electric scooters, etc. In big electricity generation plants, wind energy, hydro energy or steam energy is used as the mechanical force to create electrical energy. Let us understand all about its working in detail. 

Working of AC Generators

An AC generator works to convert the incoming mechanical energy (from any source) to alternating currents or voltage. 

A quick look at an AC generator reveals that it consists of the following parts:

1. Slip rings conduct the flow of electricity from stationary to rotating parts in the devices. These are the electrical connections that communicate power to and from the rotor.

2. The stator is the stationary part of the AC generator. The stator core is designed to minimize Eddy current losses, and hence it is made up of magnetic iron or steel alloy lamination.

3. The rotor is the rotating part of the machine. Its rotation is due to the force of the prime mover.

4. The prime mover is the primary device which is the source of the mechanical energy for the generators. AC generators may use a motor, steam turbines or diesel engines as prime movers.

5. The armature is the section of the AC generator where voltage is produced. It consists of large coils that can handle the generator’s total load current.

6. The field is the conductor coil that produces magnetic flux on receiving the voltage from the source. The output voltage of the AC generator is created when the magnetic flux in the field cuts the armature.

The working of an AC generator can be understood with the help of Faraday’s law of electromagnetic induction. It states that electromotive force is induced whenever a conductor cuts through the magnetic flux lines. The rotating armature creates flux linkages that change continuously. Hence, the electric current from the galvanometer shows positive and negative values, which hints at the creation of alternating current. Fleming’s Right-Hand Rule states the direction of the induced current in an AC generator.

Advantages of AC Generators

The main advantages of AC generators are:

1. The design of an AC generator is more simple than a DC generator, and hence it becomes easy to understand its working principle.

2. These generators operate silently, are low maintenance devices and have the lowest cost of ownership.

3. It does not require voltage matching.

4. It is possible to convert the current from AC generators to other voltage levels using AC transformers.

5. AC motors used in AC generators are easy to maintain and smell-free, unlike DC motors, which have a significant smell.

Disadvantages of AC Generators

The main disadvantages of AC generators are:

1. It is not durable as a DC generator.

2. It requires additional insulation due to the generation of large currents.

3. It needs extra caution when working on high voltages.

Conclusion

Generators are devices that convert mechanical energy into electrical energy. An AC generator is a type of generator that converts mechanical energy into alternating currents. The different parts of the generator help in converting mechanical energy into electrical energy. It is different from a DC generator in that in a DC generator current flows in one direction. An AC generator works on the established principles of electrical laws like Faraday’s law of electromagnetic induction.  

AC generators have their advantages as well as disadvantages. The advantages of an AC generator are that it can be stepped up or stepped down easily using transformers. It further reduces the transmission link size and reduces transmission losses. The losses in AC generators are less compared to DC generators. AC generators have a compact design. The major disadvantage of an AC generator is that it has high levels of extra insulation due to largely associated voltages. Further, these generators are susceptible to sparks and heating issues, which may lead to electric shocks and even fires. It is, therefore, important to increase the safety levels while using AC generators.