Optimal budget allocation for preventive maintenance of distribution system considering customer outage cost and reliability indices

Reliability of distribution power systems mainly depends on preventive maintenance planning. This paper proposes a method of preventive maintenance budget allocation for electric power distribution utilities. First, the customer outage costs are calculated by using customer damage function and actual statistical recorded interruption data. Then, the optimization problem is formulated. The total monetary costs that are the sum of utility preventive maintenance budget, utility's lost income from electricity charge due to power outage, and customer outage costs are considered as the objective function for this problem. The constraints are that the reliability indices, i.e. SAIFI and SAIDI, of all 12 regions of Thailand must not exceed the targets. The optimization is solved by linear programming method. The results of the optimization are the optimal allocated maintenance budget for each region and the associated maintenance activities which yields the most cost-effective.