Following 2017, employees of the Regional Service of Insulation and Overvoltage Protection of Ulyanovsk Distribution Grids Branch of IDGC of Volga, PJSC (member of Rosseti Group) and Insulation Services of Operating Divisions performed 2,127 tests of power equipment. They included 1,409 tests at 0.4/6/10 kV transformer substations, 687 tests at 110/35 kV substations and 31 tests at 0.4/6/10 kV overhead lines.

Besides, 1,756 inspections of stick-pedestal insulation were performed by vibroacoustic method making it possible to detect microcracks on porcelain and prevent potential technological disturbances. As early diagnostics of slowly developing defects in transformers, 356 chromatographic and 542 physical and chemical tests of transformer oil were performed. Besides, in the last year specialists of the Regional Service of Insulation and Overvoltage Protection performed thermal imaging of power equipment at 117 substations of 110/35 kV, 72 overhead lines of 35/110 kV, 1439 transformer substations of 6-10/0.4 kV.

Thermal imaging makes it possible for power engineers to detect even minor defects by fixation and conversion of infrared radiation into visible spectrum. This is one of most effective methods of equipment and structures condition diagnostics without their decommissioning, by so called contactless method. This year the branch received its own device for ultrasonic testing of high voltage porcelain structure. Before diagnostics was performed with engagement of Mordovenergo Branch services. Following the results of surveys, Branch employees replaced porcelain insulators at 9 circuit breakers VMT-110. T

imely diagnostics and monitoring of equipment condition make it possible to prevent technological disturbances in grids caused by equipment failure. All data produced in process of measurements, tests and surveys of power equipment is taken into account for formation and correction of annual production programs.