Research On The Key Technologies In Status Detection Of Oil-immersed Transformers Based On Recovery Voltage Measurement

Power system in the national industry occupies an irreplaceable position is to promote the foundation of all other industries. As the core of the electrical equipment, transformers in the power system play an unusual role. Transmission voltage level and the improvement of the capacity of the transformer a transformer out of operation or failure will result in a larger range of power outages, caused great impact to the national economy and people’s lives. Therefore, accurate detection of transformer insulating state safe and stable operation is of great significance.Recovery voltage (the Recovery Voltage Measurement RVM) is a newly proposed, does not destroy the transformer solid insulation under the premise of the transformer state detection of non-destructive testing methods. Its main advantages are without insulating oil or insulating paper samples, and to the use of insulating materials in the DC voltage polarization characteristics of the measured to recovery voltage curve and parameters, and the measured curve and parameters of oil-paper insulation damp make a diagnosis, and the overall state of aging and can be easily applied to the field test.Recovery voltage Diagnosis of oil-paper insulation system aging state research at home and abroad on the basis of the Matlab environment to build the optimization model based on the Cole-Cole oil-paper insulation to recovery voltage simulation system, a different charging voltage(Uc), charging time (tc) and the charge and discharge time simulation testing of the response voltage (tc/td) conditions, sum up the above three parameters and reply to the relationship between the voltage characteristic value, to Recovery voltage field test parameters selected based on.On top of this, the design and implementation based on the reply to the input voltage of the transformer condition monitoring system, including the three major high-voltage DC power supply, relay control module and data acquisition module. The final selection of a typical transformer, carried out under conditions of multi-parameter recovery voltage test, compare and analyze the different eras and different capacity of the transformer to recovery voltage curve characteristics (maximum Recovery Voltage Umax, center time constant tcdom and the initial slope Si), thus provide a key reference for accurate assessment of transformer condition analysis of the remaining life of the transformer.