Optimal Preventive Maintenance Planning for Electric Power Distribution Systems Using Failure Rates and Game Theory

Abstract

Current electric utilities must achieve reliability enhancement of considerable distribution feeders with an economical budget. Thus, optimal preventive maintenance planning is required to balance the benefits and costs of maintenance programs. In this research, the proposed method determines the time-varying failure rate of each feeder to evaluate the likelihood of future interruptions. Meanwhile, the consequences of feeder interruptions are estimated using interruption energy rates, customer-minutes of interruption, and total kVA of service areas. Then, the risk is assessed and later treated as an opportunity for mitigating the customer interruption costs by planned preventive maintenance tasks. Subsequently, cooperative game theory is exploited in the proposed method to locate a decent balance between the benefits of reliability enhancement and the costs required for preventive maintenance programs. The effectiveness of the proposed method is illustrated through case studies of large power distribution networks of 12 service regions, including 3558 medium-voltage distribution feeders. The preventive maintenance plans resulting from the proposed method present the best compromise of benefits and costs compared with the conventional approach that requires a pre-specified maintenance budget.

Reliability Optimization of Smart Grid Based on Optimal Failure Rate Using Distributed Generation

“…The power interrupted cost is obtained by multiplying the power interruption duration by the power interruption rate of load points. This power interrupted cost is computed as in [38] by replacing the number of customers interrupted by the power interrupted at load points. The power interrupted cost of feeder 𝑓 due to cause 𝑐 is given as…”

“…Their values are 0.026, 0.79, and 0.70 for equipment failure, tree contact, and bushfire respectively. The benefits of preventive maintenance tasks are expressed as in [38] and given by…”

“…Where 𝐿 𝑓 is the length of feeder 𝑓 and the and 𝑚 𝑐 is the costs of preventive maintenance tasks per kilometer. Benefit/cost analysis of preventive maintenance tasks is an approach for evaluating the cost-effectiveness of maintenance tasks by comparing the benefits with the costs in terms of the benefit/cost ratio [38]. The benefit/cost analysis of preventive maintenance tasks for specific cause of a feeder is given by [38] 𝐵 𝐶𝑅 = 𝐵 𝑚𝑝 𝐶 𝑚𝑝…”

“…The concerned budgets are the preventive maintenance budget and the DG generation budget. The technique used is the Cooperative Game Theory which is according to [38], the theory where optimization seeks to find a solution that results in a Pareto optimum and satisfies the requirements of all players.…”

Study of the Possibilities of Improving Maintenance of Technological Equipment Subject to Wear

“…The data required for the reliability analysis of the KSW-460NE shearer subassemblies have been collected for two years, which allowed us to determine the mean operating time between failures (MTBF) [26,27], and the mean time to repair (MTR) [27,28] and failure rate. Many of the preventive maintenance [29][30][31][32][33][34][35] work should be conducted at regular intervals. It is difficult to establish an optimum duration and it should be based on information regarding the function of failure rate, probable consequences, and costs of the preventive maintenance work, which should prevent failure, cost, and risk of the preventive maintenance work, etc.…”