Heuristic Optimization Model for Power Grid Preventive Maintenance Considering the Time-Varying Failure Rate
Power system components suffer from aging,wearing and hidden failures in operation,thus the component failure rate is increasing over time.Therefore,the preventive maintenance is required to weaken or eliminate these factors leading to the increasing of failure rate.This paper describes the growing trend of failure rate using the Weibull function and derives the average unavailability formula incorporating the time-varying failure rate.Through system state enumeration and optimal load shedding models based on AC power flow,the system failure states are selected and the corresponding minimal shedding load are calculated.Then,the analytical expressions for the system reliability indices,system outage costs,preventive maintenance costs,corrective maintenance costs incorporating the preventive maintenance rate are established,and the sensitivity of the total system cost respect to each component preventive maintenance rate is derived.Finally,this paper proposes a heuristic iterative algorithm in which the sensitivity is ranked,to find the optimal preventive maintenance.According to the studies on RBTS,it's analyzed and compared between the optimal preventive maintenance and the traditional C-level preventive maintenance from the perspective of the reliability and economy,and the cost adjustment for component preventive maintenance are studied.
NETL
NSTL
万方数据
维普
