Method and system for comparing main feed water flow quantity redundancy measurement channels of nuclear power plant evaporator

The invention relates to a method and system for comparing main feed water flow quantity redundancy measurement channels of a nuclear power plant evaporator, wherein the method includes the followingsteps: S1, formulating cross comparison standards by an uncertainty root mean square method; S2, collecting real-time water flow measurement values of the main feed water flow quantity redundancy measurement channels; S3, carrying out averaging processing of collected water flow quantity measurement values, obtaining a measured average value of the main feed water flow quantity of the main feed water flow quantity redundancy measurement channels, and taking the measured average value of the main feed water flow quantity as the reference value; and S4, calculating all the real-time water flow measurement values and the determined reference value, and carrying out cross comparison of the calculation result and the cross comparison standards. The equipment functional availability and reliability and less maintenance