Rod control rod position system is a servo mechanism for the control system and safety protection system of nuclear power plant reactors. The specific function of the rod control rod position system is to lift, lower, maintain, or quickly insert control rods. It has completed reactor start-up, adjusted reactor power, maintained power, stopped the reactor, and rapid shutdown in case of accidents. It is an important operating component of a nuclear reactor and one of the key equipment that directly affects the normal operation, safety, and reliability of the nuclear reactor.