Health State Evaluation And Short-term Capacity Increasing Of Transformer

Transformer is the key equipment of power transfer and distribution in power system,also the important asset of power grid corporation.It is of great significance to evaluate transformer health state,analyze load-ability and make short-term capacity increasing decision,for equipment lean management,supporting dispatching decision making and ensuring safe,reliable and economic operation of power system.Therefore,in view of equipment,the following studies are carried out in this paper to provide theoretical basis for system operation and maintenance schedule.Firstly,according to the defects in the traditional transformer health state evaluation method,an evaluation method for transformer health state based on historical information mining is proposed.First,association analysis method is applied to extract transformer historical information and quantify evaluation indexes with confidence level;then association weights of evaluation indexes are obtained from principal component analysis to correct index clustering space;finally,Canopy-kmeans two-layer clustering method is utilized to analyze transformers health state and assign corresponding health ratings to different clusters to guide the condition-based maintenance and operation dispatching.Secondly,a short-term transformer capacity increasing(TCI)method considering operation risk,including two stages,is proposed.First,a preliminary TCI decision constrained by hottest spot temperature(HST)and failure rate(FR)is generated.Then the economic optimal TCI decision between the preliminary TCI decision and full-loaded operation is searched as the final decision on the basis of economic risk verification in view of profit and loss of power enterprises and community.In case study,the influence of transformer service time and planned TCI time to the short-term TCI results are discussed.And the proposed method is compared with the current TCI plan of power enterprises.The results shows that short-term TCI plan can be made flexibly with the proposed method,considering both security and economy.Finally,combining the above research results and project between university and enterprise,the theory of identification and quantification of equipment risk factors,load-ability model and short-term capacity increasing method is applied on practical engineering.According to problems in operation of power grid and needs of power supply bureau,the multi-dimension risk dispatching and emergency command system in a region in southwest China is developed,and the hardware platform,software structure,develop tools and realization of functions is introduced detailedly...