配电网线路长度短,且含有多层分支及架空电缆混联线路,故障点的定位极为困难。传统基于阻抗的故障定位方法应用效果不佳,行波法具有更高的精度,但易受故障条件的影响。为此提出一种基于中国科学院测量与地球物理研究所(Institute of Geo...配电网线路长度短,且含有多层分支及架空电缆混联线路,故障点的定位极为困难。传统基于阻抗的故障定位方法应用效果不佳,行波法具有更高的精度,但易受故障条件的影响。为此提出一种基于中国科学院测量与地球物理研究所(Institute of Geodesy&Geophysics,Chinese Academy of Sciences,IGG)抗差法(以下简称IGG抗差法)的配电网多端行波故障定位方法,该方法包括两步:第1步通过网络末端测点的故障初始行波到达时间,定义与行波波速无关的R系数,并利用R系数确定故障分支;第2步利用IGG抗差法对故障位置进行精确求解,通过引入权函数对不同的测量数据赋予不同的权重,以克服行波到达时间误差带来的不利影响。PSCAD/EMTDC仿真证明该方法具有较高的定位精度,对时间误差具有强鲁棒性。展开更多
Just-in-time(JIT)part feeding is adopted by more and more automobile producers.Based on this part feeding policy,vehicles perform their assigned routes cyclically and provide stations with the exact quantity of parts ...Just-in-time(JIT)part feeding is adopted by more and more automobile producers.Based on this part feeding policy,vehicles perform their assigned routes cyclically and provide stations with the exact quantity of parts required until the next arrival of the vehicle.However,if there are uncertain travel times,a shortage of materials in stations will be caused.In this paper,the JIT part feeding optimization problem under travel time uncertainty is studied.The uncertain travel time is represented by the interval number according to the actual situation.To minimize the largest possible vehicle trip time,the optimization model is developed based on robust optimization.In the model,a route-dependent uncertain parameter is introduced.Through this model,the route of each vehicle and the parts load needed to be delivered by the vehicle can be calculated.A hybrid simulated annealing algorithm is designed to solve this model.The parts feeding planning for an engine assembly line is taken as an example.By the Monte Carlo simulation,the relationship between the line stoppage probability and the uncertain parameter is studied to obtain the final solution.The effectiveness of the method is demonstrated by this case study.展开更多
文摘配电网线路长度短,且含有多层分支及架空电缆混联线路,故障点的定位极为困难。传统基于阻抗的故障定位方法应用效果不佳,行波法具有更高的精度,但易受故障条件的影响。为此提出一种基于中国科学院测量与地球物理研究所(Institute of Geodesy&Geophysics,Chinese Academy of Sciences,IGG)抗差法(以下简称IGG抗差法)的配电网多端行波故障定位方法,该方法包括两步:第1步通过网络末端测点的故障初始行波到达时间,定义与行波波速无关的R系数,并利用R系数确定故障分支;第2步利用IGG抗差法对故障位置进行精确求解,通过引入权函数对不同的测量数据赋予不同的权重,以克服行波到达时间误差带来的不利影响。PSCAD/EMTDC仿真证明该方法具有较高的定位精度,对时间误差具有强鲁棒性。
基金This research received no external funding.This research is supported by the National Key Research and Development Program of China(Grant No.2017YFB1301600)。
文摘Just-in-time(JIT)part feeding is adopted by more and more automobile producers.Based on this part feeding policy,vehicles perform their assigned routes cyclically and provide stations with the exact quantity of parts required until the next arrival of the vehicle.However,if there are uncertain travel times,a shortage of materials in stations will be caused.In this paper,the JIT part feeding optimization problem under travel time uncertainty is studied.The uncertain travel time is represented by the interval number according to the actual situation.To minimize the largest possible vehicle trip time,the optimization model is developed based on robust optimization.In the model,a route-dependent uncertain parameter is introduced.Through this model,the route of each vehicle and the parts load needed to be delivered by the vehicle can be calculated.A hybrid simulated annealing algorithm is designed to solve this model.The parts feeding planning for an engine assembly line is taken as an example.By the Monte Carlo simulation,the relationship between the line stoppage probability and the uncertain parameter is studied to obtain the final solution.The effectiveness of the method is demonstrated by this case study.
