Optimal inspection and replacement strategy for 145 kV gas-insulated switchgear

We deal with an optimization problem of planning a maintenance strategy for 145 kV gas-insulated switchgear and apply reliability-centered maintenance approach to find an efficient and effective strategy. In a three-step sequential process, we use failure mode effects and criticality analysis to define the critical failure modes that cause the major failures of 145 kV gas-insulated switchgear, select the maintenance significant items to remove the major failure modes, and finally apply logic tree analysis to assign the appropriate maintenance task to each critical failure modes in the system. We then compare the assigned maintenance tasks with existing tasks in the installation, operation, and maintenance manuals developed in the system design and development phase. The assigned maintenance tasks in this study are compared with those in the system design and development phase by simulation, and a simple heuristic method is proposed to find optimal solutions.