Why do power plants need cooling water?

Mechanical rotation generates heat, and the buildup of this heat can damage equipment. There is lubricating oil in the friction area, and this oil will become hotter and hotter if the temperature does not decrease, the bearing temperature will increase and the bearing will be damaged.

Circulation of cooling water in the condenser is even more necessary, otherwise the steam cannot condense quickly and cannot be transformed into water for recycling.

The generator stator also needs cooling water, because the stator's insulation is likely to break down when it heats up. Cooling water is therefore necessary to ensure that it does not overheat.

If not cooled, the exhaust gases from the steam turbine - the steam that has finished the job will gradually fill the steam turbine cylinder, and there will be no pressure difference. , there youThe steam generator will not be able to produce electricity.

The pressure difference between intake and exhaust must therefore be maintained. That is, the cylinder should not be filled with low-temperature steam that has finished the job, but should be able to condense into water. The condensation of gas into water is an exothermic process, so cooling water must be used to cool the spent gas. steam (the steam that finished the job) so that it turns into water. This way, even if the back of the turbine is close to vacuum, more and more exhaust gas will fill the cylinder. Once the cooling water is interrupted, the vacuum will not be maintained and may even reach positive pressure. This time is very short, so protection against vacuum reduction is usually activated. Likewise, as the vacuum decreases, the efficiency of the steam turbine decreases. Due to the reduction in yieldt, the temperature of the steam released at the rear is naturally higher than before. Once it gets too high, the blades at the back of the steam turbine shrink. the turbine will be deformed by the high temperature and damage the turbine.

What is the main working process of the generator stator cooling water system?

The cooling forms of diesel generators are generally divided into three types : air, hydrogen and water. The cooling system of a general synchronous generator is closed and the cooling fluid is recycled.

1) Air Cooling – Air cooling is done by fans. Cold air is blown against the ends of the diesel generator windings, the generator set stator and rotor to dissipate heat. absorbs heat. Then it turns into hot air. Once the air between the stator and rotorfused, it is discharged through the iron core air duct and cooled by the cooler. The cooled air is then sent into the generator by the fan to circulate there to achieve the heat dissipation goal. The machines generally use air cooling for medium and small synchronous generator sets. ,

2) Hydrogen Cooling - Hydrogen cooling uses hydrogen as a cooling medium. The heat dissipation performance of hydrogen is better than that of air. Most large turbine generators use hydrogen cooling.

3) Water cooling - water cooling uses dual internal water cooling of the stator and rotor.

The main process flow of generator stator cooling water system is:

There are also two special subsystems, nitrogen purge system and ion purification system: nitrogen purge system is installed in the stator cooling On the upper part of the cooling water tank, there has two pipes for supplying and blowing nitrogen; The ion purification system is a branch of the stator cooling water system. It mainly circulates part of the water after the mechanical filter through ion purification. system to remove ionic impurities, then returns the stator cooling water tank.