Line Loss Analysis Of MV And LV Distribution Network Using AMI/SCADA Data

Line loss analysis plays a positive role in promoting line loss management level and planning loss reduction program.Due to lack of data and other reasons,traditional line loss analysis for MV and LV distribution network often gets low accuracy calculation results,and cannot consider some factors such as three-phase unbalance well.With the development of measurement technologies in power system,accurate data provided by advanced metering infrastructure(AMI)smart metering measurements and real-time measurements provided by SCADA system make it possible for accurate line loss analysis.Compared with traditional line loss analysis,the precise method uses more accurate data which are lifted in density from month/typical day to measurement interval set in smart meters,and can obtain the condition of line loss during study periods after calculation.The approach uses three-phase accurate calculation method and takes energy theft into consideration,both of which help promoting the accuracy of results.Additionally,by using the accurate analysis,the proportion of line loss and the influence on line loss caused by three-phase unbalance can be demonstrated more definitely.With the support of AMI/SCADA measurements data,the following works are made in this thesis:1.An accurate line loss analysis method for LV distribution network is represented by using customer's accurate voltage and current data provided by AMI smart metering measurements.Firstly,energy theft is considered in composition of theoretical line losses.A voltage difference method is designed to detect energy theft and estimate the active power loss due to the theft;Secondly,a forth-back sweep three-phase power flow algorithm is used to calculate different types of loss and their proportions in line loss in distribution network.2.With SCADA measurement data,the topology error correction in MV distribution network are designed by using voltage profiles correlation analysis.A one-by-one weight-lowering state estimation approach is put forward for energy theft detection and estimation.After the power flow is calculated,with considering the effect on variable loss and additional iron loss of Yyn0 connected transformer caused by three-phase unbalance factor,line losses of MV distribution network are calculated.Each of the proposed methods is tested with a corresponding distribution network case.Both are proved to be valid and feasible and achieve better results than traditional one.