English original text of Chapter 4 of Thermal Energy and Power Engineering Specialty Foreign Language Third EditionA power station operates using a closed steam power cycle where water undergoes vario

action points and passed through feed-water heaters before being returned to the turbine for further expansion. This process increases the overall efficiency of the power station by preheating the feed-water and reducing the amount of heat required to convert it into steam.

The boiler is the heart of the power station and is responsible for converting water into steam. The type of boiler used depends on the fuel being burned. Coal-fired boilers are common in older power stations, while newer stations may use natural gas or oil-fired boilers. The boiler consists of a combustion chamber where the fuel is burned, and a series of heat exchangers where the heat is transferred to the water to create steam. The efficiency of the boiler is determined by the amount of heat transferred to the water and the amount of heat lost to the environment.

The turbine is the component of the thermodynamic cycle that converts the heat energy of the steam into mechanical energy. The turbine consists of a series of blades mounted on a shaft that is connected to the generator. The steam enters the turbine at high pressure and temperature and is expanded as it passes through each stage of the turbine. The blades of the turbine extract energy from the steam, causing the shaft to rotate at high speed. The efficiency of the turbine is determined by the amount of energy extracted from the steam and the amount of energy lost to friction and other losses.

The generator is the component of the power station that converts the mechanical energy of the turbine into electrical energy. The generator consists of a series of coils of wire that are mounted on the shaft of the turbine. As the shaft rotates, the coils of wire rotate through a magnetic field, creating an electrical current. The electrical current is then passed through a transformer to increase the voltage to the required level for transmission over the power grid.

The condenser is the component of the thermodynamic cycle that is responsible for condensing the steam back into water. The condenser consists of a large surface-type heat exchanger where the steam is cooled by transferring its heat to the cooling water. The cooling water is then discharged back into the environment, while the condensed steam is pumped back to the boiler for reuse. The efficiency of the condenser is determined by the amount of heat transferred from the steam to the cooling water and the amount of heat lost to the environment.

The feed-water system is responsible for supplying water to the boiler and maintaining the water level in the boiler at the desired level. The feed-water is supplied to the boiler through the feed pump, which is driven by an electric motor. The feed-water is then preheated in the feed-water heaters before being fed into the boiler. The efficiency of the feed-water system is determined by the amount of heat transferred to the feed-water and the amount of energy required to pump the water through the system.

In conclusion, the closed steam power cycle used in power stations is a complex system that involves the conversion of thermal energy into mechanical and electrical energy. The efficiency of the system is determined by the efficiency of each component and the overall design of the system. Advances in technology have led to increased efficiency and reduced environmental impact, making closed steam power cycles an important source of energy for the future