Cost-Availability Analysis for Redundant Systems with Spares Inventory and Emergency Repair  
Author Tongdan Jin


Co-Author(s) Emily Zhu Fainman; Bin Xiao


Abstract Component redundancy and spare parts provisioning are the two primary means to achieve the reliability and availability goal of capital goods. The two methods are often implemented separately without considering their joint effect on the system availability and cost. This paper proposes an integrated redundancy-inventory-repair allocation model to reduce the levelized cost of system while ensuring the operational availability. To this end, Erlang-B and Erlang-C tandem queues are used to estimate the parts stockout probability under regular and emergency repairs. We introduce the levelized system cost concept for assessing the cost-benefit in terms of redundant components, base stocking policy, and emergency repair capacity. Electric vehicle charging equipment is used to demonstrate the application of the proposed integrated allocation model.


Keywords levelized system cost, electric vehicle charger, system availability, redundancy-inventory-repair allocation
    Article #:  RQD28-231

Proceedings of 28th ISSAT International Conference on Reliability & Quality in Design
August 3-5, 2023