Studies on Design of Internal Hydraulic Control Rod Drive System Loop for Nuclear Reactors

Based on the characteristics of the internal hydraulic control rod drive technology, two kinds of drive system loop schemes, the centrifugal pump continuous operation scheme and the membrane pump intermittent operation scheme are proposed and compared from the perspective of vibration, noise and energy consumption. The membrane pump intermittent operation scheme is especially calculated and discussed for a typical reactor cold commissioning case. The effects of the hydraulic cylinder leak flow rate and the control rod action interval time on the pump intermittent time and pump operation time are analyzed. Results show that the centrifugal pump continuous operation scheme applies to cases in which the control rod number and hydraulic cylinder leak flow rate are relative large. When the leak flow rate is relative small, the membrane pump intermittent operation scheme is a better choice and the pump intermittent time could be elongated and pump operation time could be shortened by selecting proper pump flow rate and the ratio of the gas to water in the water tank, which is of great help in reducing vibration, noise and energy consumption.