利用设备风险评估的检修策略优化

Maintenance Strategies Optimization of Equipment Using Risk Assessment

电力公司的重要任务是实现它的经济目标和社会责任。作为实现这些目标的最有前途的方法之一,资产管理受到了越来越多的重视。全寿命周期成本管理(LCCM)和状态检修(CBM)是资产评估中的两个有效的工具。在电力系统中应用LCCM理论和经验的时需要考虑一些特殊的因素。出于供电连续性方面的考虑,输变电设备具有很强的特殊性。一旦设备发生故障,除了设备本身遭受重大的损失之外,还可能给电网带来巨大的灾难。此外还需要考虑环境损失和社会损失等成本。因此,应该找到一个能够平衡所有这些成本的解决方案。很显然这些成本与设备的状态有关。为了获得设备状态的定量描述,采用了数理统计分析技术。设备在短期内发生故障的概率是根据设备的状态推算得出的,这与浴盆曲线理论存在一定的差异。辅助决策是第3个重要的问题。经济效益仅仅是决策依据的一个方面,LCCM将不能满足电力系统和社会的所有需要。尽管存在一些方法可以将环境损失、安全成本和社会损失等成本折算为经济指标,但还没有被广泛接受。相比而言,从风险理论之中衍生出的多目标优化则更为直观。介绍了一种优化电力系统资产管理的方法。与以前的工作相比,该技术给出了上述3个问题的综合解决方案:以设备状态为基础的故障率计算、风险评估和利用了多目标优化的辅助决策。该方法的本质是在设备自身价值和设备给系统带来的经济效益之间,在LCCM和CBM之间,以及在电力系统的技术与管理之间寻求平衡点。

Life cycle cost management（LCCM） and condition based maintenance（CBM） are two effective tools used in asset management.CBM includes equipment condition assessment,risk assessment and aid-decision making.Its emphasis is not how to maintain the equipment but how to make maintenance decision.Based on LCCM theory and experiences in other domains,operation and maintain would be about 45% of the life-cycle cost.Their optimization might reduce only 5% of life cycle costs for the most costs were determined during the design and plan.Moreover,additional environment loss and social loss would be vital too.So there should be a solution to balance all the costs.Obviously,these costs are connected with the equipment condition.To get a quantitative description of them,probability analysis technique should be introduced.Failure rate and the probability of equipment which would fail in a short period should be derived from equipment condition.Economic benefit might be only one of the decision foundations,so LCCM would not meet all needs of power system and society,especially in China.Though there are some methods to turn environment loss cost,safety loss cost and social loss cost into economic index,the conception of cost is not widely accepted.Multi-objectives optimization which is derived from risk theory would be more reasonable.To optimize asset management in power systems governed by State Grid of China,a new technology is thus proposed.Compared with previous work,this technology gives a comprehensive solution to three problems： failure rate calculation based on equipment condition,risk assessment for power system and decision-making based on multi-objectives optimization.It can be regarded as a balance between the value of equipment themselves and benefits that they can bring to power systems,a balance between LCCM and CBM,and finally,a balance between technologies applied and management of power system.