控制棒驱动机构是核反应堆的关键设备,其是否正常运行直接关系到核反应堆的安全性。该文对水力驱动控制棒系统在摩擦力卡棒和倒置等极限工况下的停堆问题,提出了步进缸内腔卸压的解决方法,并在热态实验研究的基础上,建立了正置落棒和倒置插棒的理论模型。分析了极限落棒过程参数(位移、速度和棒内外差压)的变化规律,得到了摩擦力卡棒和倒置等极限工况下控制棒插入堆芯的能力。结果表明:在极限工况下水力驱动控制棒有足够能力插入堆芯。 Control rod drive mechanism is the key equipment of nuclear reactor, and its normal operation is directly related to the safety of nuclear reactor. In this paper, a solution to the pressure relief in the cylinder of the stepper cylinder is put forward on the shutdown of the hydraulic control rod system under the limit operating conditions such as the friction rod and the inversion. On the basis of the experimental study in hot conditions, The theoretical model of positive and negative rods. The variation law of the process parameters (displacement, velocity and differential pressure inside and outside the bar) of the falling bar was analyzed. The ability of the control bar inserted into the core under the ultimate operating conditions such as the friction bar and the inversion was obtained. The results show that the hydraulic control rod has sufficient ability to insert into the core under the limit conditions.