Classification of Distribution System Quiz and Flashcards

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of the distribution system in a power system?

To distribute power to consumers for utilization.

How can the transmission system be compared to in the human body?

Arteries.

What is the main function of the distribution system?

To supply the ultimate consumer with electricity.

Why is it difficult to distinguish between transmission and distribution systems?

Because what was considered high voltage before is now considered low voltage. Signup and view all the answers

What is the equivalent of the distribution system in man's circulatory system analogy?

Capillaries. Signup and view all the answers

What is the primary objective of the electrical distribution system?

To convey electrical energy from generating stations to consumers. Signup and view all the answers

What is the main purpose of an electrical distribution system?

To efficiently and safely deliver electricity to end-users while ensuring reliability and stability of the system. Signup and view all the answers

What components are included in an electrical distribution system?

Power lines, transformers, circuit breakers, fuses, and meters. Signup and view all the answers

Define an electrical distribution system.

A network of electrical components used to supply power to buildings, homes, and industries. Signup and view all the answers

What is the role of a transformer in the electrical distribution system?

To distribute electricity to lower voltage levels. Signup and view all the answers

Describe the layout of a typical low tension distribution system.

It generally consists of feeders, distributors, and service mains. Signup and view all the answers

What is the difference between the transmission system and the distribution system?

The transmission system carries electricity at high voltages over long distances, while the distribution system delivers electricity at lower voltages to end-users. Signup and view all the answers

What are the two classifications of a distribution system based on the nature of current?

D.C Distribution System, A.C. Distribution System Signup and view all the answers

Why is the overhead system generally employed for distribution?

It is 5 to 10 times cheaper than the equivalent underground system. Signup and view all the answers

How can the distribution system be classified based on the scheme of connection?

(a) radial system, (b) ring main system, (c) interconnected system Signup and view all the answers

What is the main reason for the widespread use of alternating current over direct current?

Alternating voltage can be conveniently changed in magnitude by means of a transformer. Signup and view all the answers

Which type of construction system is used where overhead construction is not feasible?

Underground system Signup and view all the answers

Why is the A.C. system preferred for distribution of electric power?

It is simpler and more economical than the direct current method. Signup and view all the answers

What is the purpose of the secondary distribution system in an a.c. distribution system?

It includes the range of voltages at which the ultimate consumer utilizes the electrical energy delivered to it. Signup and view all the answers

How are single phase domestic loads typically connected in a secondary distribution system?

Single phase domestic loads are connected between any one phase and the neutral. Signup and view all the answers

What is the voltage between any two phases in a secondary distribution system employing a 400/230 V, 3-phase, 4-wire system?

400 V Signup and view all the answers

Why is a d.c. supply sometimes necessary in an electric power distribution system?

For certain applications like variable speed machinery (d.c. motors), electrochemical work, and areas needing storage battery reserves. Signup and view all the answers

What is the purpose of distribution substations in a secondary distribution system?

Distribution substations step down voltage to 400V and deliver power by 3-phase, 4-wire a.c. system. Signup and view all the answers

How are 3-phase 400 V motor loads typically connected in a secondary distribution system?

3-phase 400 V motor loads are connected across 3-phase lines directly. Signup and view all the answers

What is the principal disadvantage of the two-generator method in obtaining a 3-wire DC system?

Two separate generators are required. Signup and view all the answers

How is the neutral wire obtained in a 3-wire DC system using a 3-wire DC generator?

From the common point of the coils of high reactance and low resistance. Signup and view all the answers

In the two-generator method for obtaining a 3-wire DC system, what flows through the neutral wire?

Out of balance current (I1 - I2). Signup and view all the answers

Why was the 3-wire DC generator developed as an alternative to the two-generator method?

The two-generator method was costly due to needing two separate generators. Signup and view all the answers

What type of winding does the 3-wire DC generator have?

Armature winding. Signup and view all the answers

What does each generator in the two-generator method supply?

Each generator supplies the load on its own side. Signup and view all the answers

Study Notes

Distribution System in Power Systems

The purpose of the distribution system is to deliver electrical energy from the transmission system to individual consumers.
The transmission system can be compared to the human body's arterial system, while the distribution system is comparable to the capillary system.

Function of Distribution System

The main function of the distribution system is to receive power from the transmission system and deliver it to consumers at a safe and usable voltage.

Comparison with Transmission System

It is difficult to distinguish between transmission and distribution systems because they are interconnected and have overlapping functions.
The transmission system operates at a higher voltage and is used for long-distance transmission, while the distribution system operates at a lower voltage and is used for local distribution.

Circulatory System Analogy

The equivalent of the distribution system in the circulatory system analogy is the capillary system.

Primary Objective

The primary objective of the electrical distribution system is to provide a reliable and efficient supply of electrical energy to consumers.

Components of Distribution System

An electrical distribution system includes components such as transformers, conductors, and distribution substations.

Role of Transformer

The role of a transformer in the electrical distribution system is to step down the voltage to a safe and usable level for consumers.

Layout of Low Tension Distribution System

A typical low tension distribution system has a radial or loop layout, with a transformer feeding multiple consumers.

Classifications of Distribution Systems

Distribution systems can be classified based on the nature of current as AC (alternating current) or DC (direct current).
Distribution systems can also be classified based on the scheme of connection as overhead or underground systems.

Overhead System

The overhead system is generally employed for distribution due to its lower cost and ease of installation.

Underground System

The underground system is used where overhead construction is not feasible, such as in urban areas.

AC System

The AC system is preferred for distribution of electric power due to its ability to be transformed to different voltage levels and its lower transmission losses.

Secondary Distribution System

The purpose of the secondary distribution system is to provide a safe and usable voltage to individual consumers.

Connection of Single Phase Domestic Loads

Single phase domestic loads are typically connected in a secondary distribution system between one phase and the neutral wire.

Voltage Between Phases

The voltage between any two phases in a secondary distribution system employing a 400/230 V, 3-phase, 4-wire system is 400 V.

DC Supply

A DC supply is sometimes necessary in an electric power distribution system for specific applications, such as in telecommunications or electrolysis.

Distribution Substations

The purpose of distribution substations in a secondary distribution system is to provide a reliable and efficient supply of electrical energy to consumers.

Connection of 3-Phase Motor Loads

3-phase 400 V motor loads are typically connected in a secondary distribution system between the three phases.

Two-Generator Method

The principal disadvantage of the two-generator method in obtaining a 3-wire DC system is that it requires two separate generators, which can be expensive and inefficient.

3-Wire DC Generator

The 3-wire DC generator has a specialized winding that allows it to provide a neutral wire for 3-wire DC systems.
In the two-generator method, each generator supplies one half of the total voltage, with the neutral wire being the midpoint between the two generators.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Learn about how distribution systems can be classified based on the nature of current, type of construction, and scheme of connection. Understand the differences between DC Distribution System and AC Distribution System, and why AC system is predominantly used for electric power distribution.

Classification of Distribution System

Choose a study mode