FIELD: diagnostics of power transformers, namely circuits of arc-suppressing contacts with current-limiting resistance of fast action regulator under load, wherein selector, contactor and drive mechanism are combined in a single block, and transformer windings are coupled in a star.
SUBSTANCE: diagnostics is performed by comparing current oscilloscope patterns to analogical oscilloscope patterns, made during pre-commissioning tests during switching of selector from one position to another without opening the tank of regulator under load and draining transformer oil of contact system of regulator under load simultaneously of all three phases. Oscilloscope recording is performed according to a circuit which includes inductivity of winding of power transformer relatively to contacts of high voltage winding and the neutral. Time constants of transfer process of current alteration are compared in case of its drop. Disruption of contact system of arc-suppressing contacts is characterized by increase of time constant compared to pre-commissioning tests, and presence of coil shorting in current-limiting resistance is characterized by reduction of the constant. Tear of current-limiting resistance is characterized by time constant equal to zero.
EFFECT: prevented pollution of environment, reduced working hours, possible diagnosing under any weather conditions.
4 dwg
