Abstract :
A method is proposed based on the generalized reactivity concept for monitoring the subcriticality level of an ADS system during normal operation at any degree of subcriticality, at safe conditions and without significantly altering the reactor power. Rather than a standard control rod calibration at BOL in terms of reactivity, this method implies a control rod calibration in terms of the multiplication coefficient (ksub) via pulsed source or source jerk techniques.