Real-time online early warning device and method for insulation faults of transformer

Abstract

The invention relates to a real-time online early warning device and method for insulation faults of a transformer. The device is characterized in that a partial-discharge ultrahigh frequency sensor is mounted at a transformer inspection hole or an accident oil drain valve; the partial-discharge ultrahigh frequency sensor is connected to a partial-discharge ultrahigh frequency signal conditioner through a coaxial cable; the partial-discharge ultrahigh frequency signal conditioner is connected to an internal A / D (Analogue-to-Digital) acquisition card of an industrial personal computer through a coaxial cable; an iron core grounding current sensor is mounted at a transformer core leading-out wire and a grounding grid; the iron core grounding current sensor is connected to an iron core grounding current signal conditioner through a shielding signal wire; the iron core grounding current signal conditioner is connected to the internal A / D acquisition card of the industrial personal computer through the shielding signal wire; and a CAN (Controller Area Network) card of the industrial personnel computer is connected to a CAN network. The real-time online early warning device completes original sample data display and storage, and insulation fault signal analysis and calculation in real time on line, and immediately provides early warning information of transformer insulation faults according to the transformer working condition information acquired through the CAN communication card; and fault latency time is less than 1s.

Description

technical field [0001] The invention relates to a real-time online early warning device for a fault, in particular to a real-time online early warning device and an early warning method for a transformer insulation fault. Background technique [0002] As the power system develops towards high voltage and large capacity, the voltage level and single capacity of power transformers are also increasing, and the reliability of its operation is directly related to the safety and stability of the power system. Once an accident occurs to a high-voltage large-capacity power transformer, it will cause a large-scale power outage, and even endanger the stable operation of the entire power system. The accident involves a large area, high maintenance costs, long periods, and huge economic losses. Statistical analysis shows that an important reason for large-scale power transformer accidents is insulation failure, and the condition of the insulation system directly determines the reliabili...

AI Technical Summary

Problems solved by technology

[0003] However, due to the lack of theory and technical limitations, the current research on transformer insulation faults focuses on protection after faults and insulation aging monitoring, and there is no fault warning method and corresponding device for the time being.

When these protective devices operate or the insulation aging monitoring device finds that the insulation aging is serious, it is very likely that irreparable losses have been caused, or even major safety accidents.

However, the vast majority of insulation faults have a development process. If the development process between normal and faulty transformer insulation can be accurately captured in real time, it is possible to realize real-time fault warning of transformer insulation.

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