In order to optimize the refueling operation and improve the efficiency of the pressurized water reactor nuclear power plants, kinematic models of the main refueling equipment such as refueling machine, underwater fuel transfer system and fuel handling machine are established, respectively. General formulas for total time of reactor refueling are derived based on the models. The parametric analysis method for refueling operations is developed. Finally the models and methods are proved to be proper and effective by the parameter calibration of a typical reactor.