Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
152 words
A method of determining the distance to a fault in a hightension d.c. transmission line according to the time of propagation of electromagnetic energy along the line by recording at one end of the line the moment corresponding to the arrival of the leading edge of an electromagnetic wave generated at the fault and propagating from the fault toward said end of the line along a loop formed by the wires of said line, recording at the same end of the line the moment corresponding to the arrival of the leading edge of the same electromagnetic wave generated at said fault and propagating from the fault toward said end of the line along a loop formed by the wiRes of said line and the earth; measuring the time interval between said moments, and computing the fault distance to said one end of the line as a function of the measured time interval.
Claim 2
Independent Claim
152 words
A method of determining the distance to a fault in a hightension d.c. transmission line according to the time of propagation of electromagnetic energy along the line by recording at one end of the line the moment corresponding to the arrival of the leading edge of an electromagnetic wave generated at the fault and propagating from the fault toward said end of the line along a loop formed by the wires of said line, recording at the same end of the line the moment corresponding to the arrival of the leading edge of the same electromagnetic wave generated at said fault and propagating from the fault toward said end of the line along a loop formed by the wiRes of said line and the earth; measuring the time interval between said moments, and computing the fault distance to said one end of the line as a function of the measured time interval.
Claim 3
Independent Claim
231 words
A device for determining the distance to a fault in a high-tension d.c. transmission line, comprising: voltage dividers connected to the different poles of said line and functioning as voltage transmitters of voltages proportional to the instantaneous values of voltages across said poles of the line, and a unit receiving electromagnetic waves for detecting the two electrogamgnetic waves travelling along said loops from the fault, said unit comprising at least two transformers whose primary windings are connected to said voltage dividers, the respective secondary windings of said transformers being so combined in pairs that some of them are connected in series aiding and produce a signal proportional to the electromagnetic wave travelling from the fault toward said end of the line along one of said loops, while the remaining secondary windings are connected in series opposition and produce a signal proportional to the electromagnetic wave travelling from the fault toward said end of the line along the other of said loops; rectifiers, with the input of each of them connected to the respective pairwise-combined secondary windings of said transformers, making it possible to produce a signal of the same sign irrespective of the polarity of the electromagnetic wave travelling in one of said loops, and a time-interval measuring unit whose input is connected to the outputs of said rectifiers for measuring the difference in time of arrival of said electromagnetic waves.
Claim 4
Independent Claim
231 words
A device for determining the distance to a fault in a high-tension d.c. transmission line, comprising: voltage dividers connected to the different poles of said line and functioning as voltage transmitters of voltages proportional to the instantaneous values of voltages across said poles of the line, and a unit receiving electromagnetic waves for detecting the two electrogamgnetic waves travelling along said loops from the fault, said unit comprising at least two transformers whose primary windings are connected to said voltage dividers, the respective secondary windings of said transformers being so combined in pairs that some of them are connected in series aiding and produce a signal proportional to the electromagnetic wave travelling from the fault toward said end of the line along one of said loops, while the remaining secondary windings are connected in series opposition and produce a signal proportional to the electromagnetic wave travelling from the fault toward said end of the line along the other of said loops; rectifiers, with the input of each of them connected to the respective pairwise-combined secondary windings of said transformers, making it possible to produce a signal of the same sign irrespective of the polarity of the electromagnetic wave travelling in one of said loops, and a time-interval measuring unit whose input is connected to the outputs of said rectifiers for measuring the difference in time of arrival of said electromagnetic waves.
Claim 5
Dependent Claim
47 words
A device as claimed in claim 2 comprising capacitors connected in series with the primary windings of said transformers to make sure that the result of measurements of said time interval does not depend on the level of the operating voltage in said high-tension d.c. transmission line.