Based on the study through the analysis data of gas dissolved from oil once the paroxysmal failure happened to tow main transformer,the paper brings some opinion on judgment of transformer failure through the application of dissolved gas analysis.

The determination method of sudden breakdown of the safety accessories of liquefied gas tank car in operation is expounded; The causes to the breakdown are analyzed; And the emergency disposition measures are put forward.

According to the area where there is a lack of oxygen and the duration when the lack of oxygen lasts we can determine the risk area and the risk duration where and when a sudden accident occurs.

Analysis of a 220 kV line trip caused by the developing fault;

Based on the fault phase selection module and fault type determination module in fault processing procedure of microcomputer protection software design,the simulation calculation and network training have been done for the determination of re close phase in adoptive re close when system developing fault occurs.