In rotating electrical machinery and power systems, hydrogen is commonly employed in which equipment, primarily for high-efficiency cooling and reduced windage losses?

Introduction / Context:
High-power turbo-generators dissipate megawatts of heat in their rotors and stators. Efficient cooling is essential to maintain insulation life and machine reliability. Hydrogen cooling has long been used in very large generators due to the gas’s high specific heat, excellent thermal conductivity, and low density (reducing windage losses).

Given Data / Assumptions:

• Consider equipment at utility or large industrial scale.
• Cooling performance and parasitic losses are key design concerns.
• Hydrogen handling systems (seals, purging, safety) are available only in specialized installations.

Concept / Approach:
Hydrogen-cooled generators enclose the active parts in a sealed casing filled with hydrogen, sometimes with direct-cooled conductors. Benefits include lower gas density (reduced windage), superior heat transfer, and better acoustic performance. Transformers are generally oil-cooled, not hydrogen-cooled. Circuit breakers and MCBs use different interrupting media (air, SF6, vacuum, oil) and do not rely on hydrogen for bulk cooling.

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