The internal structure of a nuclear power plant typically consists of a primary and a secondary loop system. The reactor is the core of the nuclear power plant. The heat energy released during the reactor's operation is carried away by the coolant in the primary loop system, which is used to generate steam. Consequently, the entire primary loop system is known as the "nuclear steam supply system," analogous to the boiler system in a thermal power plant. To ensure safety, the entire primary loop system is housed within a sealed facility called a containment, thus ensuring safety is not compromised during both normal operation and in the event of an accident. The secondary loop system, which drives the steam turbine generator set for electricity generation, is essentially the same as the steam turbine generator system in a thermal power plant. Since the inception of nuclear power plants, the three main types of power generation reactors that have become industrially mature are: light water reactors, heavy water reactors, and graphite gas-cooled reactors. They are correspondingly applied to three different

In nuclear power plants, the core of modern nuclear power generation has been established.