Nuclear power station reactor-cavity water-injection cooling system

The invention relates to a nuclear power station reactor-cavity water-injection cooling system. The nuclear power station reactor-cavity water-injection cooling system comprises a reactor cavity which is arranged in a containment vessel of a reactor, a pressure vessel which is arranged in the reactor cavity, and a thermal-insulation barrier which is arranged between the reactor cavity and the pressure vessel and surrounds the pressure vessel. The nuclear power station reactor-cavity water-injection cooling system also comprises an external water-injection system and a high-position water-injection system arranged in the containment vessel. The external water-injection system comprises an external water source, an external water-injection pipe connected to the external water source, a reactor-cavity water-injection pump arranged on the external water-injection pipe, a first isolating valve and a second isolating valve, and the first isolating valve and the second isolating valve are arranged respectively at an upstream position and a downstream position of the reactor-cavity water-injection pump. The external water-injection pipe goes through the containment vessel and then is connected to the bottom of the thermal-insulation barrier. The high-position water-injection system comprises a high-position water-injection tank, a high-position water-injection pipe for connecting the bottom of the high-position water-injection tank and the external water-injection pipe, and a third isolating valve arranged on the high-position water-injection pipe. The nuclear power station reactor-cavity water-injection cooling system has stable and reliable performances, can effectively relieve the serious accident result, and can ensure the integrity of the pressure vessel of the reactor in a serious accident.