Researches On The Application Of Gas Sensor In On-line Monitoring System For Gas Dissolved In Transformer Oil

The operation reliability of the power transformer as the key equipment in electrical power systems, influences operation security of electrical power systems directly.In order to avoid the fault of transformer, we should reinforce the monitor on varies transformer fault and predict transformers'faults in advance. So the diagnostic technique has been becoming an important question for study or discussion. Now an important method of insulated monitor to full of oil electric equipment such as transformer is to test the gas ,which is dissolved in the insulated oil by means of DGA. This method prevents many faults of transformer successfully. In this paper, the importance of transformer faults online monitoring technology and its recent development actuality are introduced briefly. Based on the study of occurring and dissolving theory for the components and contents of gases dissoloved in transformer oil,H2 and CO can be used to reflect internal insulation faults of operating transformer. The relationships between oil-dissolved gases and the transformer fault types are further analyzed. Online extracting gases technology using macromolecule osmotic membrane is studied, capability of osmotic membrane F₄6 is discussed too. Studying the principle and method of many sensitive elements which are used to detecting the gases dissolved in oil, sensors of MQ series that author selected have obvious selectivity and higher accuracy when they detect gases of H₂ and CO. Finally ,the structure and constitute of transformer fault online monitoring system is introduced. Hardware structure and main character of transformer online monitoring system are stated in detail.