Types of DC Generators - Separately & Self Excited DC Generator | Shunt, Series & Compound Generator

Summary

This video introduces the different types of DC generators, explaining their construction and working principles. It begins with a breakdown of the two main parts of a DC generator: the stator and rotor, and their components. The video then details the types of DC generators: separately excited and self-excited, with further subdivisions into shunt, series, and compound generators. It explains how these generators function, their wiring configurations, and the roles of field and armature windings. The video concludes with the working principles of both long and short shunt compound generators.

Takeaways

• ⚙️ DC generators are divided into two main parts: stator (stationary) and rotor (rotating).
• 🔋 Stator components include yoke, pole cores, pole shoes, field windings, brushes, and end covers.
• 🔄 Rotor components include the armature winding, commutator, and shaft.
• 🌀 DC generators are classified into two types: separately excited and self-excited generators.
• 🔗 In separately excited DC generators, the field winding is powered by an external DC source.
• 💡 In self-excited DC generators, the field winding is powered by the armature, relying on residual magnetism for initial excitation.
• 📐 Self-excited generators are further divided into three types: shunt, series, and compound generators.
• 🔄 In shunt generators, the field winding is connected parallel to the armature; in series generators, it is connected in series.
• 🔧 Compound generators combine shunt and series winding connections, with two types: long shunt and short shunt compound generators.
• 📊 Voltage equations for these generators account for armature resistance and brush contact drops, specific to the generator type.

Q & A

What are the main parts of a DC generator?

A DC generator is mainly divided into two parts: the stator and the rotor. The stator consists of stationary parts like the yoke or magnetic frame, pole cores, pole shoes, field windings, brushes, brush holders, and end covers. The rotor consists of rotating parts such as the armature, armature winding, commutator, and shaft.

How many types of DC generators are there based on winding connection?

DC generators are divided into two main types based on winding connection: separately excited DC generators and self-excited DC generators. The self-excited DC generator is further divided into three types: DC shunt generator, DC series generator, and DC compound generator.

What is a separately excited DC generator?

In a separately excited DC generator, the field winding is supplied from an external, separate DC source. The excitation to the field winding is separate from the armature, which is why it is called a separately excited DC generator.

What are the main characteristics of a separately excited DC generator's field winding?

The field winding of a separately excited DC generator consists of a large number of turns with thin wire, resulting in high resistance to limit the field current.

How does a self-excited DC generator work?

A self-excited DC generator works due to residual magnetism in the field poles. When the generator starts, the residual flux develops a small emf in the armature, which drives a small current through the field winding. This process continues, gradually increasing the induced emf until the generator reaches its rated voltage.

What are the types of self-excited DC generators?

The self-excited DC generators are divided into three types: DC shunt generator, DC series generator, and DC compound generator.

How is the field winding connected in a DC shunt generator?

In a DC shunt generator, the field winding is connected in parallel with the armature winding, and the load is connected across the armature terminals.

What is the main difference between a DC series generator and a DC shunt generator?

In a DC series generator, the field winding is connected in series with the armature winding and the load, whereas, in a DC shunt generator, the field winding is connected in parallel with the armature winding.

What is a DC compound generator?

A DC compound generator is a combination of both DC shunt and series generators. There are two types of DC compound generators: long shunt compound generator and short shunt compound generator.

How does the field winding connection differ between a long shunt and a short shunt compound generator?

In a long shunt compound generator, the shunt field winding is connected across the series field winding. In a short shunt compound generator, the shunt field winding is connected only across the armature winding.