Improved Fuzzy Stochastic PERT and its Application in the Overhaul of the Generator Units

In this paper, three particularities that the maintenance staff often ignores in overhaul of the generator units are concluded. Based on the practices of 14 electric power plants in China, we get the fuzzy impact degrees accordingly, and then improve the traditional PERT using fuzzy stochastic theory in maintenance scheduling. The procedures using the improved fuzzy stochastic PERT are discussed in details in order to calculate the critical path and the sub-critical paths more accurately and reliably, and the forward float, backward float and the common float are invented to analyze the consequence of the proposed method. Finally an example in Guodian Shizuishan power plant maintenance is given to illustrate the proposed method and the floats analysis.