Turbo-generator excitation winding turn-to-turn short circuit fault diagnosis method

Abstract

The invention discloses a turbo-generator excitation winding turn-to-turn short circuit fault diagnosis method. The method comprises the following steps: 1) a generator finite element model is established, and a rotor fundamental frequency vibration and a phase angle caused by different excitation winding turn-to-turn short circuit faults are calculated to serve as a sample set of fault diagnosis;and 2) rotor vibration data during operation of the generator is collected online and in real time, the correlation degree between the vibration data and the fault sample set is obtained, and the fault degree and the fault position of the excitation winding turn-to-turn short circuit are obtained. According to the turbo-generator excitation winding turn-to-turn short circuit fault diagnosis method provided by the invention, according to the influence of electromagnetic and heat imbalance caused by the excitation winding turn-to-turn short circuit faults on the vibration of the rotor, the vibration characteristic is extracted, good diagnosis sensitivity is achieved, a new detection device does not need to be installed, thereby improving the fault diagnosis efficiency, and the method has the advantages of being simple and easy to implement and high in reliability.

Description

technical field [0001] The invention relates to the technical field of generators, in particular to a method for diagnosing short-circuit faults between turns of excitation windings of turbogenerators. Background technique [0002] In today's power grid, thermal power generators frequently participate in power grid peak regulation, and the operating burden of large turbogenerators increases, and the unit failure rate increases, especially for the field windings that have long been accompanied by high-speed rotation of the generator rotor, inter-turn short-circuit faults occur frequently. Turn-to-turn short-circuit faults of the excitation winding will cause the excitation current of the generator to increase, the reactive power to decrease, and the vibration of the unit to deteriorate. In severe cases, the rotor ground fault may occur, causing the generator to be forced to stop. Therefore, it is necessary to conduct on-line monitoring for the inter-turn short circuit fault o...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is the lack of sensitivity when the generator load is running

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