Method and system for obtaining parameters of synchronous generator

Abstract

The invention provides a method and system for obtaining parameters of a synchronous generator. The method comprises the following steps of: respectively creating corresponding simulation models according to test data of a no-load characteristic test, a no-load de-excitation test, a D-axis load rejection test and a Q-axis load rejection test; fitting rotor voltage data and rotor current data in the data of the no-load characteristic test of a generator to generate a saturation characteristic curve so as to modify stator voltage data, the rotor voltage data and the rotor current data of the test data of the no-load characteristic test, the no-load de-excitation test, the D-axis load rejection test and the Q-axis load rejection test and then generating a stator voltage test waveform; inputting generator default parameters and the modified rotor voltage data and rotor current data in the test data into the simulation models; and modifying the simulation waveform according to the stator voltage test waveform, and outputting an instant time constant, D-axis parameters and Q-axis parameters. The invention fully considers the influences of nonlinear factors of saturation, vortex and the like, improves the accuracy of the parameters and provides reliable technical evidence for the transient stability calculation and dynamic stability calculation of a power system.

Description

technical field [0001] The invention relates to power system analysis technology, in particular to a method and system for acquiring parameters of synchronous generators in the power system. Background technique [0002] With the increasing capacity and scale of the power system, the safe and stable operation of the power system has become the primary issue. Numerical simulation technology (such as EMTP, BPA, etc.) is widely used in power system stability analysis. Reasonable and accurate generator parameters in numerical simulation technology have decisive significance for accurate calculation and analysis of power system. [0003] At present, power system analysis and calculation generally use the design value of synchronous generator parameters or use conventional test methods (such as no-load short-circuit test, three-phase short-circuit test, etc.) to measure generator parameters. The disadvantage is that it cannot measure a complete set of generator parameters At the ...

AI Technical Summary

Problems solved by technology

[0003] At present, power system analysis and calculation generally use the design value of synchronous generator parameters or use conventional test methods (such as no-load short-circuit test, three-phase short-circuit test, etc.) to measure generator parameters. The disadvantage is that it cannot measure a complete set of generator parameters At the same time, the offline measurement cannot effectively consider the saturation and eddy current effects of the generator, so that there are large errors in the calculation and analysis results, and it cannot meet the requirements of the rapidly developing power system for its analysis and calculation.

The main problem of generator online parameter time-domain identification method is first of all that it can only be compared with the parameters obtained by the traditional method to show its degree of credibility. It is often encountered that the parameters obtained by different tests or the same test have large differences. That is, there are many solutions to the problem, so the accuracy of the measurement cannot be explained; secondly, the environment in which the synchronous generator is located during the test is complex, affected by the influence of adjacent motors and disturbances from the grid side, etc. will affect the accuracy of the test results; in addition, During the test, the synchronous generator is in normal operation state, and the input disturbance should not be too large

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