A capacitive current testing method, device and system based on different frequency phase current

Abstract

The invention provides a different-frequency phase current-based capacitance current test method, device and system. The method includes the following steps that: the test terminal m of a current output module is connected with the a phase end, b phase end and c phase of a switch cabinet electrification indicating device, the grounding terminal o of the current output module is electrically connected with the grounding end of the switch cabinet electrification indicating device, a resonant inductor is electrically connected between two output terminals of the current output module, current transformers of each phase are electrically connected between an electrification indicating sensor capacitor and the switch cabinet electrification indicating device; and a set of different-frequency current signals of which the magnitudes are equal and of which the frequencies are continuous is outputted; maximum different-frequency voltages of each phase and different-frequency current of each phase of the switch cabinet electrification indicating device under the different-frequency current signals of different frequencies are obtained; and ground capacitance and ground capacitance current ofeach phase of a neutral-point-ungrounded system are calculated. The method has the advantages of simple test loop, high safety and the like. With the method adopted, the ground capacitance of each phase of a power system can be calculated separately.

Description

technical field [0001] The present disclosure relates to the technical field of electric power systems, and in particular to a capacitive current testing method, device and system based on different frequency phase currents. Background technique [0002] In the neutral point ungrounded system, when the line is single-phase grounded, the current flowing through the fault point is the capacitive current generated by the line-to-ground capacitance. Most of the faults in the neutral point ungrounded system are caused by the excessive capacitive current when the line is single-phase grounded, and the arc is not easy to self-extinguish. my country's power system stipulates that when the capacitive current of the 10kV and 35kV systems is greater than 30A and 10A, an arc suppression coil should be installed to compensate the capacitive current. In order to determine the compensation capacity of the arc suppression coil, a capacitive current test should be carried out. In addition, ...

AI Technical Summary

Problems solved by technology

[0004] The embodiment of the present invention provides a capacitive current testing method, device and system based on different frequency phase currents to solve the problems of cumbersome operation and poor safety in the prior art

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