METHOD OF REDUCED PRIMARY CURRENT RECOVERY OF CURRENT TRANSFORMER IN TRANSIENT MODE Russian patent published in 2018 - IPC H01F27/42 H01F38/28 

FIELD: electricity.

SUBSTANCE: method of reduced primary current recovery of a current transformer in transient mode consists in the fact that secondary current of the current transformer is converted into the voltage proportional to it in a real time in an analogue form, which is then converted into a digital code, which is supplied to the input of a SC current parameter calculation unit. Then it is again converted into the analogue signal, which is supplied to the input of the power amplifier, whose output is the output. The voltage in a real time in an analogue form is supplied to the inputs of the constant time-delay units, the number of which is one less than the number of parameters of the short-circuit current. Then, to the inputs of analogue-to-digital converters, the signal from which is fed to the inputs of the SC current parameter calculation unit, from the values of the signals at the inputs of the SC current parameter calculation unit a vector of the measurement results of the secondary current is formed at different time intervals, spaced apart by the amount of the sampling interval (Δt), which is substituted into the system of equations as the right-hand side of this system describing the transient process in the power system and the solution of which is an analytic expression describing the short-circuit current, which is reduced.

EFFECT: reducing the error of recovery of the reduced primary current of the current transformer in the transient mode, facilitating the solution stability of the problem of the reduced primary current recovery and providing the possibility of the reduced primary current recovery of the current transformer in real time.

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