1. Air cooling
Air cooling adopts the method of fan air supply. Cold air is used to blow the ends of the windings of the generator set, the stator and the rotor of the generator set to dissipate heat. The cold air absorbs the heat It turns into hot air. After the air between the stator and the rotor first merges, it is discharged through the air duct of the iron core and cooled through the cooler. The cooled air is then sent into the generator by the fan for circulation to achieve the purpose of heat dissipation. Medium and small synchronous generators generally use air cooling. For reference only (Answer by Fujian Yanan Electric)
2. Hydrogen cooling
Hydrogen cooling uses hydrogen as the cooling medium. The heat dissipation performance of hydrogen is better than that of air. Most turbine generators are cooled by hydrogen.
3. Water cooling
Water cooling uses double water internal cooling of the stator and rotor. The cold water external water system of the stator water system flows through the water pipe to the water inlet ring installed on the stator seats, and flows to each coil through the insulating tube respectively. After absorbing the heat, it is collected through the insulated water pipe to the water outlet ring installed on the machine base. It then drains into a water system outside the generator for cooling. The cooling of the rotor water system first enters the water inlet support installed on the side shaft end of the exciter, then flows into the center hole of the rotor shaft, then flows to the water collecting tank along several meridional holes, and then flows to each coil through the insulating tube. After the cold water absorbs heat, it flows into the water outlet tank through the insulating pipe, then flows through the drainage hole on the outer edge of the water outlet tank to the water outlet support, and is led out by the water outlet main pipe. Since the heat dissipation performance of water is much higher than that of air and hydrogen, newly built large-scale generator sets generally use water cooling. For reference only (Answer from Fujian Yanan Electric)