Which distribution system is commonly used?

Question

Examoogle · Accepted Answer

radial

Explanation: The radial distribution system is the most commonly used system because of its simplicity and low initial cost. In this configuration, power is supplied to the consumers through a single path starting from a single substation or feeding point.

Working Principle: In a radial system, a single feeder emanates from a substation and branches into distributors to provide power to consumers. Because the flow of power is unidirectional (from source to load), the design is simple, requiring minimal switchgear and protection equipment compared to interconnected systems.

Key Formulas: $V_{drop} = I \cdot R$ — Voltage drop in a radial feeder segment; $I_{total} = \sum I_{branch}$ — Summation of load currents

Key Points: Most economical for low-density areas.; Simplest protection scheme (fuses or simple circuit breakers).; High supply vulnerability: a fault in the main feeder results in total outage for downstream loads.; Voltage at the end of the line is lowest due to cumulative voltage drops.

Advantages: Lowest initial installation cost; Simple design and operation; Easy fault location and maintenance

Disadvantages: Low reliability: single point of failure; Significant voltage drop at the tail end; Cannot support multi-source power injection

Applications: Rural electrification; Low-density residential areas

Additional Info: Radial systems are primarily used in India for rural and semi-urban distribution due to budget constraints.. Ring main systems are preferred in urban areas to provide higher reliability by feeding from two directions.

Answer: D is correct — The radial system is the most common distribution topology due to its extreme cost-effectiveness and architectural simplicity.

Exam Tip: Always remember that in exams, reliability is inversely proportional to cost; choose 'Radial' for cost-sensitive answers and 'Ring/Mesh' for reliability-critical answers.

Related Questions

Discussion (0)