A phase-specific identification method for single-phase ground faults in low-voltage power distribution systems

Abstract

A method for phase identification of single-phase ground faults in low-voltage power distribution systems, which collects real-time bus three-phase voltage values, neutral point voltage values, and three-phase current values ​​at each monitoring point in low-voltage power distribution systems. After a ground fault occurs, first According to the three-phase voltage criterion, the faulted grounding phase is determined. When the voltage criterion condition is not met, the judgment is made according to the current mutation amount. Finally, the faulty grounding phase is determined through a comprehensive judgment based on the current mutation amount combined with the phase voltage phase change value. The application improves the accuracy of ground fault phase judgment and effectively ensures the safe operation of the low-voltage distribution network.

Description

technical field [0001] The invention belongs to the technical field of power systems, and relates to a single-phase fault grounding diagnosis method for a low-voltage distribution network. Background technique [0002] In my country, the construction scale of 6kV and 10kV low-voltage distribution network is getting larger and larger, and it is a power grid system directly oriented to urban and rural residents' electricity consumption, industrial power supply and commercial power consumption. With the widespread application of electronic products and the promotion of new energy sources such as wind power, photovoltaics, pumped storage power stations, and large-scale energy storage, the structure of distribution networks has become increasingly complex. Usually, in order to ensure the power supply demand, the low-voltage power distribution system is allowed to run for a short time (generally no more than 2 hours) after the single-phase grounding. Therefore, it is necessary for...

AI Technical Summary

Problems solved by technology

As the distribution network structure becomes more and more complex, the sensitivity of the above method is not high, and the misjudgment rate is high

The existing methods of line selection and phase selection for grounding faults in low-voltage distribution networks are increasingly unable to meet the requirements of increasingly large and complex distribution networks.

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