Universal testing system and method of line selection apparatus of low-current grounding system

Abstract

The invention discloses a universal testing system and method of a line selection apparatus of a low-current grounding system. A function circuit simulation model is established, a plurality of distribution network outlet ground capacitors are simulated by using a plurality of capacitors with different impedance values, a single-phase voltage source simulates a secondary zero-sequence voltage source at a single-phase ground fault time of a distribution network, and a ground arc suppression coil and a parallel medium resistor are connected; primary line selection function comparison testing on a tested device is carried out by using the function circuit simulation model; a distribution network simulation model is established based on actual parameters, different types of feeder circuit ground faults are simulated, and comprehensive line selection performance comparison testing is carried out on the tested device in detail according to the distribution network simulation model; recording data of the field ground fault of the distribution network are collected, a fault working condition is reproduced, and a fault recording playback simulation model is constructed. According to the invention, the actual working condition of the field ground fault of the distribution network is restored to the greatest extent; and the influence on grid safety by testing projects like artifical grounding and the like can be eliminated.

Description

technical field [0001] The invention relates to a general testing system and method for a line selection device of a small current grounding system. Background technique [0002] The single-phase grounding line selection device of the small current grounding system (hereinafter referred to as the line selection device) is used for the grounding fault line selection and positioning of the power supply system where the neutral point of the transformer is not effectively grounded. When a single-phase grounding fault occurs, the line selection device should be able to accurately and reliably select the faulty line and faulty phase, so that the operator can eliminate the fault in time, prevent the single-phase grounding from developing into two-point or multi-point grounding, and effectively avoid the expansion of the power failure range , to promote the safe and stable operation of the power grid. [0003] The technology of small current grounding line selection is developing r...

AI Technical Summary

Problems solved by technology

[0003] The technology of small current grounding line selection is developing rapidly. Many devices with different working methods, different line selection principles, hardware structures and software algorithms have different line selection performances. It is very important to accurately grasp the development of line selection technology and the performance of various types of devices. caused great difficulty

The technology and devices for line selection of small current ground faults in China have always lacked systematic testing technology means. The existing technology cannot fully and accurately simulate the characteristics of small current ground faults, and many field test items are only for a few common simple fault types. test, not universal

Images