Steam Power Generation Units: Air-Cooled / Hydrogen-Cooled Cooler

Steam Power Generation Units: Air-Cooled / Hydrogen-Cooled Cooler

Generator Air Cooler

Function: Directly cools the generator's stator, rotor, and core using air (commonly used in small and medium-sized steam turbine generators).

Structure:

Copper tubes with aluminum fins

Built-in fan (rotor-driven or independent fan)

Air circulates within the unit and is cooled by external water or air through the air cooler

Features:

Simplest structure, lowest cost, and easiest maintenance

No explosion-proof or sealing requirements

Lower heat dissipation efficiency (poor thermal conductivity of air)

Applicable Capacity: Generally ≤60 MW small steam turbine generators

Generator Hydrogen Cooler

Function: Uses hydrogen as an internal circulation medium to cool the generator, then transfers the heat from the generator to the cooling water via the hydrogen cooler.

Principle:

The generator is filled with high-purity hydrogen (>98%) at 0.3–0.5 MPa

The thermal conductivity of hydrogen is approximately 7 times that of air, and its density is only 1/14 that of air

The hot hydrogen is cooled by cooling water in the hydrogen cooler and then recirculated

System Components (more than just a single cooler):

Hydrogen cooler body (4–6 units in parallel)

Sealing oil system (leak prevention)

Hydrogen drying, purity monitoring, pressure control, and explosion protection

Applicable Capacity:

60 MW–450 MW: Pure hydrogen cooling

450 MW–1,800 MW: Rotor hydrogen cooling + stator water cooling (dual water internal cooling)