Research On Transformer Outage Model And Load Capacity

The stable operation of the power grid is related to the national political,economic security and social stability,so it has been paid more and more attention in recent years.Transformer is an indispensable equipment which is applied in transmission,distribution and other aspects.The reliability indexes include multi-source data processing,equipment condition evaluation,transformer failure probability and overload capacity evaluation.In this paper,the following studies are carried out.Firstly,according to the data sources and data platform diversity,a multi-source data processing system design is proposed.Based on the analysis of electric transmission and transformation equipment state assessment data,the system designs the functions including data preliminary processing,cross platform access,preliminary cleaning,quality evaluation model,specification conversion and data output function.In addition,the electric transmission and transformation equipment multi-source data processing system is applied to big data analysis platform,to distribute heterogeneous storage of big data and efficient retrieval technology.The system focuses on the parallel transmission technology for analysis of big data,and builds a model framework of big data full coupling analysis,in order to provide data support for transformer equipment and power grid system.Secondly,the existing state evaluation methods which put too much emphasis on the rigid index are relatively fixed,and the current risk assessment systems take samples of the single transformer equipment failure probability as the transformer node failure probability.So a transformer interval outage model based on state evaluation is proposed.The model calculates the failure probability of secondary equipment and measuring equipment,corrects the failure probability of switch equipment,and obtains the transformer interval probability which is based on the functional decomposition method and reliability analysis.Considering transformer state difference evaluation,the results show that the model could provide more accurately data support for the extraction of transformer outage probability in the risk assessment.Finally,on the basis of above research,aiming at the problem of suspending power grid construction and solving the demand of high power consumption,and the problem of only considering the hot spot temperature or top oil temperature,a new model based on Hot spot temperature-Failure load probability-Economy-Transformer Load Capacity(HFE-TLC)is proposed.Based on the modified hot spot temperature model and the transformer failure probability model,the constraints of hot spot temperature and failure probability are determined.Fulfilled the above constraints,and combined the economic losses and economic benefits,the conception of probability loss is proposed to study the influence of the economy on the overload operation.The results indicate that the modified hot spot temperature model could more accurately characterize the actual hot spot temperature.By analyzing the influence of transformer service time and planned running time on short term overload operation,the model provides comprehensive suggestions for decision-making and proposes the theoretical support for the power grid risk assessment,which is driven by the quantitative analysis of multi-factors in the short outage scene.