Abstract:
—The purpose of this paper is to describe and
discuss an approach to estimate the Reliability and
Availability values of the Uninterruptible Power
Supply (UPS) systems using Monte-Carlo simulation
method. In this method, the failure rates O , and
availability (A) of the major components in the UPS
are simulated by the use of random number
generators that produces deterministic reliability
parameters that try to mimic results that would be
obtained from field trials. Reliability parameters such
as the system’s Failure Rates O , Mean Time
Between Failures (MTBF), System Availability (A),
and System Unavailability (W), can be achieved and
thus can be used as an indication of the reliability
level of the UPS systems. In this paper, the method are
applied to five UPS configurations (online with and
without bypass, offline, line-interactive with
buck/boost transformer and line-interactive with
ferroresonant transformer), and comparisons on the
results obtained from this method were made to the
results from other reliability estimation method such
as the Reliability Block Diagram (RBD), Boolean
Truth Table and Field Data estimation method.
