Development of a personal-computer-based system for control rod worth determination in a nuclear reactor

A new and compact system based on a personal computer is developed for online determination of control rod worth in the upgraded 10-MW core of the Pakistan Research Reactor (PARR-1). The system utilizes a locally designed pulse acquisition card interfaced with the PC that features multiple inputs, high signal resolution, and fast data acquisition in a single slot card. The system acquires the pulse signals from the start-up channels and computes the system negative reactivity along with the associated errors using the inverse kinetic rod drop algorithm. The effect on reactivity measurements of relative detector position on the core is discussed. The results of rod worth measurements under different core conditions on the PARR-1 and PARR-2 cores are described. The application of the system for reactivity determination in the case of a highly subcritical core and large gamma background is discussed.