Automatic control method and system for non-uniform boron dilution prevention protection of nuclear power plant

The invention relates to an automatic control method and system for non-uniform boron dilution prevention protection of a nuclear power plant, and under all working conditions of a reactor from power operation to complete unloading, the following steps are executed: monitoring a reactor coolant system in real time; judging whether a forced circulation losing signal, a natural circulation losing signal and a residual heat removal system non-access signal are detected or not; if yes, obtaining the average temperature of the reactor coolant; and controlling the non-uniform boron dilution prevention protection action according to the average temperature of the reactor coolant. By means of the steps, the problem caused by false triggering of the non-uniform boron dilution prevention protection under the complete discharging working condition can be avoided, starting or non-starting of the non-uniform boron dilution prevention protection action is the automatic control process, the misoperation risk of an operator