The Research And Design Of On-Line Detection System For The Capacity And Loss Of Distribution Transformers

Power transformer is not only one of the most important equipments in powersystems, but also failure-prone equipment. The development of online monitoringsystem for transformers is crucially important for safe and reliable operation of powersystems. Owing to open-circuit loss, short-circuit loss and capacity are main technicalparameters of the transformers and these parameters have great significance fortransformer fault diagnosis and energy conservation, the realization the online detectionof these parameters is the key to condition monitoring. This study based on manyliteratures at home and abroad has made comprehensive and thorough research to onlinedetection open-circuit loss, the short-circuit loss and capacity of distributiontransformers and some results have been made as the following four points. Base on theanalysis of the structure and working principle of transformers, this study proposes themethods for the open-circuit loss, short-circuit loss and capacity online detection. Thesimulation platform which is used to do the related online measurement experiments hasbeen developed.The main work of this subject mainly embodies on the followingaspects:①A new online detection method for short-circuit impedance is proposed, whichshows concrete functions and derivation steps. Further more the author deeply studiesthe methods for online detection of the open-circuit loss and the short-circuit loss ofdistribution transformers. All of these provide theoretical basis for the design of onlinedetection system.②On the basis ofanalysing the advantages and disadvantages of the differenttransformer capacity detection methods, a new method for online detection ofdistribution transformers’ capacity is proposed, and corresponding simulations areconducted to verify the correctness of the proposed method.③Thesoftware platform of the transformer losses and capacity online detectionsystem software platform is developed with LABVIEW, which mainly achievecollecting electrical parameters, analysing signals and computes data. The softwareplatform provides the merits of friendly interface, simple operation and good practicality,and the functions of data storage and analysis, results printing and report generation.④Based of successfully debugging the online detection system some experimentsto detect the losses and capacity of transformer are conducted. And the results verify the correctness of the methods which this paper proposed and show that the system canmeasure the losses and capacity of the distribution transformer accurately. The methodswill provide some theoretical and technical reference for the practical application ofengineering.