FIELD: physics; electricity.
SUBSTANCE: during operation of the controlled power transformer the measurement of the instantaneous values of the voltage of primary winding, the voltage and current of the secondary winding is conducted. The secondary values are equated to the primary values. The difference in the given voltages of the primary and secondary windings is determined. The inductive component of the voltage difference is simultaneously determined, reading from the obtained voltage difference the operation of the given secondary current and active resistance of windings. The instantaneous values of the derivative of the given secondary current on time are determined. The instantaneous values of inductance of the windings as the ratio of the instantaneous values of the inductive component of a voltage difference to the instantaneous values of the derivative of the given secondary current are found. The obtained values of inductance in the period are averaged. The power of active coil losses and the effective value of the given secondary current are determined, which are used for determining the active resistance of windings. When averaging the instantaneous values of inductance the peak values are excluded. The relative deviations of the received values of inductance and active resistance of windings from the values are determined from a known good transformer. Further there is comparison of the obtained deviations with the predetermined setting and if at least one of these deviations is more than the assigned setting, then a conclusion is made about the defective state of the windings of the controlled transformer and a signal is transmitted to turn it off.
EFFECT: increase in reliability and effectiveness of control and protection of the windings of a transformer.
2 tbl, 3 dwg
Authors
Dates
2008-11-27—Published
2007-06-22—Filed