电力变压器局部放电内嵌式监测系统研究

Research on Embedded Monitoring System for Transformer's Partial Discharge

针对变压器内部局部放电产生的超声波信号特征,设计基于电-声联合检测法的内嵌式监测系统。该系统可以在线同步检测出变压器局部放电产生的2路电流脉冲信号和6路超声波信号。硬件上采用12芯光纤传输,可有效抑制现场监测的电磁干扰,提高测量的灵敏度;软件上采用集成模块化设计,有助于提高系统运算的速率和可靠性。通过对地下变电站3台在线运行主变压器的测试,表明研制的在线监测系统能够实现变压器局部放电信号的在线实时监测,可为变压器的状态检修提供大量可信的数据依据。

An embedded monitoring system that was used to acquire partial discharge （PD） ultrasonic in transformer was designed based on electro-acoustic combined detection method. This on-line monitoring system could synchronously detect two circuits＇ current signals caused by transformer PD： multiplex pulses and 6 circuits＇ ultrasonic signals. 12 core optical fiber transmission was used in hardware to suppress electromagnetic interference in field monitoring and improve the sensitivity of measurement; as well as the modular design method was adopted in software to improve the data rate and reliability of system operation. For the on-line operation of three transformers in the underground substation, the measured data show that the on-line monitoring system can detect PD signal of transformer on time, which can provide lots of creditable data for the condition-based maintenance of transformers.