Reactor power coefficient measuring method

The invention belongs to the physical technical field of reactors of nuclear power plants, and in particular relates to a reactor power coefficient measuring method. After nuclear fission, the reactorreach stable criticality, the reactor core power is P1, the reactor core reactivity is rho1, and positive reaction is introduced to the reactor, so that the reactor power is increased continuously, the positions of starting and finishing control rods are kept unchanged during the period; negative reactive feedback is brought to the reactor core as the power increases due to a heating effect of afuel; the final reactor core reactivity is gradually reduced to 0; and the reactor core power is P2, the reactor core reactivity is rho2, and the specific value of change rho1-rho2 and powder change P1-P2 of the reactor core reactivity is calculated to obtain the power coefficient. Test measurement under a zero power platform after different reactors are critical can be conducted, and the reactorpower coefficient is obtain