Digital gas protection and oil flow surge monitoring integrated device and method for transformer

Abstract

The invention relates to a digital gas protection and oil flow surge monitoring integrated device and method for a transformer. The device comprises a transient oil flow characteristic quantity measurement module, a switching value input module, a signal conditioning and acquisition module and a digital core module, wherein the transient oil flow characteristic quantity measurement module is connected with the signal conditioning and acquisition module, and the signal conditioning and acquisition module and a switching value output module are connected with the digital core module. According to the invention, digital information of transient oil flow in an oil conservator connecting pipe is acquired in real time, an action oil flow value representing the oil flow surge intensity is obtained by calculation, and a protection principle and criterion are constructed by using the significant difference of the calculated value under different operation conditions of the transformer, therebyrealizing reliable, fast and sensitive discrimination and removal of faults inside an oil tank of the transformer, and being not affected by the excitation surge current. Meanwhile, the action oil flow value is compared with a preset overcurrent threshold value and a quasi-overcurrent threshold value so as to judge whether the transformer has abnormal overcurrent or not, thereby achieving on-linemonitoring and evaluation for the operation state of the transformer.

Description

technical field [0001] The invention belongs to the field of power systems, and relates to a transformer digital gas protection and oil flow surge monitoring integrated device and method, which are used for reliable, fast and sensitive identification of internal faults in oil tanks of oil-immersed power transformers. Background technique [0002] As a key main power equipment, the transformer occupies a pivotal position in the power system, and its stable operation is an important prerequisite to ensure the reliable transmission, flexible distribution and safe use of electric energy in the entire power system. When an internal fault occurs in the transformer, if the relay protection device refuses to operate or cannot act in time, the transformer body may be damaged due to the pressure impact of the internal fault, and even cause an explosion or fire accident; In case of misoperation, the economic losses caused by power outages will be inevitable. Especially for high-voltag...

AI Technical Summary

Problems solved by technology

[0007] Traditional mechanical gas protection uses mechanical structures such as floats, springs, and baffles to sense gas generation and oil flow surges. There are two main problems: First, the spring mechanism can only reflect the flow rate of the oil flow. Once it exceeds the preset threshold The trip signal is issued without measuring and analyzing the characteristic information of the oil flow surge change, so the protection reliability is low; second, the mechanical structure is soaked in the insulating oil for a long time, and the sludge generated by the shedding of oxides and the deterioration of the insulating oil will adhere to the On mechanical components such as relay baffles, floats or springs, it seriously affects the accuracy and sensitivity of its actions

Images