The fixed winding adopts a separate water cooling system. The water-cooled winding conductor has a conductive circuit and a waterway. Each group of wire rods contains several empty copper tubes and several solid copper wires. with cooling water to remove the wire rods. The empty copper tube and the solid copper wire are connected at the end of the thermal wire rod slot. The empty copper tube and its empty copper tube are bundled and welded with special water. An empty copper tube is connected to the insulated water branch pipe. The main inlet (or) collector pipe cooling water enters from the end. Cooling of the wire rod is carried out by the other end of the flow circulation to remove heat. generated by the wire rod
The hydrogen cooling system includes a fan housing and the hydrogen cooler is entierly placed inside the generator. The ventilation system adopts radial flow closed circulation ventilation to generate electricity. The machine is arranged alternately in the axial direction with 13 air zones, 6 air inlet zones and 7 wind zones. Two axial fans (each on the steam and excitation side) are installed and rotated. of the iron core and penetrates the rear. The air flows in the radial direction of the iron core in the air inlet area and enters the air gap in the rotating air duct; trough for cooling the rotating winding; the other part is folded again to cool the iron core in the air duct of the iron core machine base and enters the cooler; the hydrogen cooled by the cooler enters in front of the fan. The recirculation alternately enters the radial flow. ventilation to ensure uniform cooling of the generator core winding and rereduce thermal stress of structural parts and local heat.
Disadvantages: Hydrogen has strong explosive characteristics when mixed with air in a certain proportion. Hydrogen generator must be installed. The cooling system prevents the leakage of the hydrogen shaft seal and the sealing oil system makes the system complex and tedious to operate.
What impact does the ventilation and cooling method of the group hydroelectric power station generator has on the plant generator stage layout?
Stator iron The core adopts radial ventilation and the rotor adopts ventilation and cooling system diagonal flow air gap.
Advantages of using hydrogen as a cooling medium:
1) Hydrogen has low density and can reduce wind energy consumption.
2) Hydrogen has a heat transfer rate and a coefficienthigh heat transfer performance, which can guarantee the effective power output of materials per unit volume.
The cooling of synchronous generators is divided into two types: external cooling and internal cooling.
1. External cooling: including air cooling and hydrogen cooling.
Air Cooling: The cooling medium is air, i.e. air is used to carry away the heat generated due to losses in the generator. This method has a simple structure, but the cooling efficiency is not high. The maximum installed capacity can reach around 100 MW.
Hydrogen cooling: The cooling medium is hydrogen, that is, hydrogen is used to remove heat. High cooling capacity compared to air. The ventilation loss is low, but the structure is complexe and requires hydrogen storage equipment. The maximum installed capacity can reach around 200 MW.
2. Internal cooling: including stator internal water cooling, rotor internal hydrogen cooling, etc.
Internal cooling (direct cooling method): the cooling medium is water, oil or hydrogen, that is, hydrogen, Water or oil passes through the inside of the wire to carry heat away directly from it. the two aforementioned surface cooling methods. The high cooling capacity can reduce the size of the generator, save materials and facilitate the manufacturing of large capacity generators. However, the generator structure is complex, copper loss is large, iron loss and. the mechanical losses are low and the total loss is similar.