Three-core power cable phase current detection method based on magnetic sensors

Abstract

The invention relates to a three-core power cable phase current detection method based on magnetic sensors and belongs to the current detection technology field for electromagnetic measurement. The method comprises steps that the three magnetic sensors with intervals of 120 DEG are employed, magnitudes of tangential components of a surface magnetic field of a three-core power cable along the cable circumferential direction are measured; the three sensors are collimated with cores of A, B and C phases of the three-core power cable; a de-coupling algorithm is employed, and current magnitudes and directions of the cores of the A, B and C phases of the three-core power cable can be directly acquired according to values outputted by the three magnetic sensors and circumferential geometric dimensions of the three-core power cable. Through the method, change of the surface circumferential magnetic field of the three-core power cable is detected, effective detection on current of each core of each phase in the three-core power cable can be realized, a problem that a traditional inductive current measurement device can not measure current of each phase of a three-core power cable in the prior art can be solved, and real-time online detection on current of each phase of the three-core power cable can be realized on the basis of the method.

Description

technical field [0001] The invention relates to a phase current detection method of a three-core power cable based on a magnetic sensor, and belongs to the technical field of current detection in electromagnetic measurement. Background technique [0002] Three-core power cables are often used in power transmission projects below 35kV. The three-core power cables A, B, and C phase core wires are evenly distributed in pairs at 120 degrees in the circumferential direction, and the three-phase core wires use a common shielding layer. In order to ensure the safe and stable operation of the urban power supply system, the real-time detection of the phase current of the power cable is of great significance. In principle, it is possible to evaluate the operation status of each phase of the cable by detecting the change of the core current of each phase in the three-core power cable in real time, so as to ensure the normal and reliable operation of the three-core power cable. Howeve...

AI Technical Summary

Problems solved by technology

As mentioned above, with the traditional detection method and measurement device based on the principle of electromagnetic induction, it is impossible to measure the current of each phase core wire of a three-core power cable, and most of the current detection methods and detection devices for power cables are realized Measurement of relevant parameters that indirectly reflect cable operating characteristics, such as cable temperature measurement, etc.

Although the results of indirect measurement can also reflect whether there is a defect in the power cable, whether there is a hidden danger of failure, or even a failure that has occurred, the measurement is delayed, and the location and type of the defect or failure cannot be clearly diagnosed. big limitations

Images