Delta–wye (Δ–Y) conversions: Are these transformations useful and commonly applied in certain circuit-analysis and design scenarios?

Introduction / Context:
Delta–wye (Δ–Y) conversions allow complex three-node resistor networks to be simplified into equivalent forms. These transformations are standard in both power and electronics contexts.

Given Data / Assumptions:

• Linear, passive resistor networks with three interconnected nodes.
• Objective is to simplify analysis or enable series/parallel reductions.
• Applies under DC and AC steady state (for resistors; generalized to impedances if reactive components exist).

Concept / Approach:

A Δ network (three resistors each between a pair of nodes) can be transformed into an equivalent Y (three resistors, each from a node to a common junction) and vice versa. Proper formulas maintain identical terminal resistances between any pair of nodes, preserving circuit behavior at the terminals.

Step-by-Step Solution:

Verification / Alternative check:

Compute any two-terminal equivalent resistance of the original and converted networks; matching values confirm correctness. Simulation tools or bridge measurements can validate the equivalence experimentally.

Why Other Options Are Wrong:

• Δ–Y is also helpful in electronics (e.g., bias networks, sensor bridges), not just three-phase power.
• Resistances need not be equal; formulas work for arbitrary values.
• The method is not restricted to DC; with complex impedances it applies in AC as well.

Common Pitfalls:

Swapping node labels during conversion or misapplying the formulas, which leads to incorrect equivalent values. Careful node mapping prevents errors.

Final Answer:

True