During the Spring Festival, in order to ensure the reliable power supply of Hubei main network, State Grid Hubei maintenance company specially invited an "intelligent power doctor" - laser photoacoustic spectroscopy online gas monitoring device for the main transformer of 500kV Xinglong substation in Qianjiang. This is the first time that this new device has been applied to 500kV transformer in our province.

500 kV Xinglong substation is the "heart" of load in central Hubei. Before the festival, State Grid Hubei maintenance company overcame the difficulty of low temperature, paid close attention to the construction in rainy days, and completed the installation of monitoring device on February 5.

It is reported that the transformer is filled with insulating oil. In operation, when thermal fault, discharge fault or component aging occurs inside the transformer, the insulating oil will crack to produce hydrogen, methane, carbon dioxide and other fault gases. The content of fault gases is closely related to the type and severity of the fault. By on-line monitoring the content of these fault gases, the hidden faults inside the transformer can be found as soon as possible.

It is understood that in the past, oil chromatography technology and infrared broad-spectrum light source photoacoustic spectrum gas detection technology were mostly used for on-line monitoring, but these monitoring devices have some defects, such as complex structure, insufficient accuracy and cross interference between the measured gases. The laser photoacoustic spectroscopy online monitoring overcomes these defects, and has high reliability, and basically does not need routine maintenance.

"The traditional on-line monitoring device is unstable, and the accuracy of the data is always not very reassuring. We must do another oil chemical analysis to determine it. Now we have tested this new device, which is very stable, and we can judge it according to its data in the future." Wu Xiaorui, the person in charge of the oil and chemical specialty of the electrical test class of the company's Substation Maintenance Center, said that the "intelligent power doctor" has improved the working stability of the transformer and greatly reduced the workload of the monitoring personnel.