A capacitance current test method, device and system based on the frequency sweeping method

Abstract

The invention provides a capacitance current test method, device and system based on a frequency sweeping method. The method comprises: electrically connecting the test terminal m of a capacitance current test device current output module to the a phase end a, the b phase end, and the c phase end of a switchgear cabinet charge indicator device, electrically connecting the grounding terminal o of the capacitance current test device current output module to the grounding end of the switchgear cabinet charge indicator device, and electrically connecting a resonant inductor between the two outputterminals of the current output module; outputting a group of equal different-frequency current signals with continuous frequencies; obtaining the maximum different-frequency voltage under different-frequency current signals; calculating the total capacitance to ground and capacitance current to ground of a neutral-point ungrounded system according to the maximum different-frequency voltage, the different-frequency current, and the capacitance of the charge indicating sensor. The method has a simple test circuit, can calculate the capacitance to ground of each phase of a power system, does notneed power outage, has high safety, and is suitable for testing the capacitance current test of the ungrounded system.

Description

technical field [0001] The present disclosure relates to the technical field of power systems, in particular to a capacitive current testing method, device and system based on a frequency sweep method. 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, in order to verify whet...

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Problems solved by technology

[0004] Embodiments of the present invention provide a capacitive current testing method, device and system based on the frequency sweep method to solve the problems of cumbersome operation and poor safety in the prior art

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