HVDC system applicability beyond long distance Is the statement “HVDC systems are preferable only for long distances” correct?

Introduction / Context:
High Voltage Direct Current (HVDC) transmission is known for economic advantages over long distances due to lower line losses and no reactive power flow. However, its applicability extends well beyond distance economics. The question probes broader engineering reasons for choosing HVDC.

Given Data / Assumptions:

• HVDC link vs HVAC alternatives.
• Consider submarine cables, asynchronous interties, power flow control.
• No quantitative cut-off distance is provided; focus on principle.

Concept / Approach:

HVDC is preferred for: (1) long-distance overhead lines; (2) very long submarine cables (where HVAC capacitive charging makes AC infeasible); (3) asynchronous interconnection between grids of different frequencies; (4) precise and rapid power flow control and damping of oscillations; (5) connecting remote renewable generation. Hence saying “only for long distances” is false.

Step-by-Step Solution:

Verification / Alternative check:

Real-world installations (e.g., cross-sea interconnectors, back-to-back HVDC stations) validate HVDC selection where distances may be short but technical needs dominate.

Why Other Options Are Wrong:

Options that qualify “only for overhead” or “only above 800 kV” miss other major use cases and technologies (VSC-HVDC, LCC back-to-back).

Common Pitfalls:

Equating HVDC strictly with very long lines; ignoring cable charging issues and asynchronous ties.

Final Answer:

False