Reliability Modelling of the DC Uninterruptible Power Supply

The paper will present the method to predict the reliability parameters of the DC Uninterruptible Power Supply (UPS) by using the Reliability Block Diagram (RBD) method. Important quantitative system´s reliability indices such as Failure rate, Mean Time Between Failures (MTBF), Availability and Unavailability, can be calculated from the RBD models. In this paper, two configurations of DC UPS (with and without generator) were considered and comparisons on the resultant reliability parameters by using the proposed RBD method were discussed in detail. Actual field data from industrial best practice are used to validate the results of the analytical model.