Diagnostic method for estimating turn-to-turn short circuit fault degree of large generator exciting windings

Abstract

A diagnostic method for estimating the turn-to-turn short circuit fault degree of large generator exciting windings belongs to the technical field of test and includes the steps of firstly acquiring stator vibration signals, stator current, exciting current and an internal power angle of a faulted generator, calculating the ratio of the number of short-circuit turns to the total number of turns by the aid of the signals, and stator vibration signals, stator current, exciting current, an internal power angle and parameters of a generator running normally, simultaneously reckoning in the influence of turn-to-turn short circuit positions on the short circuit degree and obtaining the fault degree value of turn-to-turn short circuit of the exciting windings. The diagnostic method has the advantages of simplicity, feasibility, reliability of diagnostic results and the like, and effectively overcomes the shortcoming that the traditional monitoring technology giving priority to rotor vibration performance is capable of only judging whether generators have turn-to-turn short circuit faults of the exciting windings or not instead of estimating the short circuit fault degree, so that important reference materials can be provided for maintenance of the generators.

Description

technical field [0001] The invention relates to a method for diagnosing the inter-turn short-circuit fault degree of a large-scale generator rotor excitation winding, which belongs to the field of testing technology. Background technique [0002] The turn-to-turn short circuit of the excitation winding is one of the most common electrical faults in large generators. The turn-to-turn short circuit fault will lead to rotor vibration, and even develop into rotor grounding, rotor winding burnout, generator loss of magnetization, generator component magnetization, etc., endangering power generation machine and system security. [0003] There are various diagnostic methods for inter-turn short-circuit faults, but most of the existing technologies can only judge whether there is an inter-turn short-circuit fault in the generator, and cannot diagnose the inter-turn short-circuit fault based on the data that can be measured by existing sensing technologies. Estimate and identify the...

AI Technical Summary

Problems solved by technology

[0002] The turn-to-turn short circuit of the excitation winding is one of the most common electrical faults in large generators. The turn-to-turn short circuit fault will lead to rotor vibration, and even develop into rotor grounding, rotor winding burnout, generator loss of magnetization, generator component magnetization, etc., endangering power generation machine and system security

[0003] There are various diagnostic methods for inter-turn short-circuit faults, but most of the existing technologies can only judge whether there is an inter-turn short-circuit fault in the generator, and cannot diagnose the inter-turn short-circuit fault based on the data that can be measured by existing sensing technologies. Estimate and identify the degree of failure

In this way, the most reasonable handling measures cannot be taken according to the specific conditions of the fault.

Once an inter-turn short circuit fault is found, even if a slight fault occurs in some critical periods that are not suitable for shutdown, it can only be forced to take shutdown measures, which brings great inconvenience to industrial production and people's lives

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