Requirement
This study involved determining the influence of the tolerances applied to the various parameters of a motor driven pump and its power supply system, on its capacity to change from a low speed regime to a high-speed regime. This equipment delivers a cooling function for a nuclear application.
Realization
To perform this study, CAPSIM employed an internally developed reliability study tool based on the coupling of Phimecasoft and PSIM software :
- realization and validation of a model of the system using PSIM software
- application of Phimecasoft software to program a reliability analysis which could use numerical simulation to calculate the impact of the mean values on the correct realization of the function (sizing value) and the impact of the standard deviation on each parameter (the standard deviations, once limited, allowed the acceptance ranges of the parameters to be defined for use during acceptance testing of the system.
Results
The combination of the PSIM and Phimecasoft tools has much shorter calculation times than with the conventional Monte Carlo method of standard analysis and allows :
- optimum sizing of the components with the constraint of fulfilling the function of the system
- definition of the dominant acceptance criteria for the function and an optimum distribution of margins in the acceptance criteria (e.g. relaxation of criteria which are costly to obtain)
- the guarantee that system components are interchangeable allowing the shortest possible re-qualification times following maintenance.
Launching a reliability analysis on the Phimecasoft software
