Method and device for testing low-frequency oscillation inhibition capability of power system stabilizer

Abstract

The invention discloses a method and a device for testing the low-frequency oscillation inhibition capability of a power system stabilizer. According to the method, a linear relation between a power transmission line in a power system and an oscillation frequency generated by a tested generator is obtained; the length of the power transmission line is adjusted for a plurality of times; corresponding oscillation frequencies of the power transmission lines with different lengths in a low-frequency oscillation period and a damping ratio of the power system are calculated; and under the same frequency, the damping ratios corresponding to the state that the power system stabilizer is not put into use and the state that the power system stabilizer is put into use are compared and analyzed, and the low-frequency oscillation inhibition capability effect of the power system stabilizer is determined. According to the method, on the premise that any parameter of the generator and the matched power system stabilizer PSS is not changed, by adjusting the power transmission line in the power system, each frequency point in a test frequency band can be simulated, a real and credible test result iseffectively obtained for the low-frequency oscillation suppression capability of the tested power system stabilizer PSS, and the test efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a test method for the ability of a power system stabilizer to suppress low-frequency oscillations. Background technique [0002] With the continuous expansion of the scale of the power grid and the increasingly complex structure (interconnection of AC and DC lines, and the increase of long-distance power transmission lines), low-frequency oscillation events of 0.2-2.5 Hz in the power system occur from time to time, and low-frequency oscillations will affect the voltage and frequency of the power system. In severe cases, it will cause out-of-synchronization of grid-connected units, which is one of the key issues that threaten the safe and stable operation of the power system. Power system stabilizer PSS is currently the most mature and effective means of suppressing low-frequency oscillations, and is widely used in all levels of power grids. Its principle is to increase ...

AI Technical Summary

Problems solved by technology

Although this method of changing the moment of inertia of the unit can easily adjust the oscillation frequency, it is necessary to re-adjust the relevant parameters of the power system stabilizer PSS after changing the moment of inertia of the unit each time. It takes time and affects the test efficiency. On the other hand, unauthorized modification of the PSS parameters of the power system stabilizer may cause abnormal output of the PSS of the power system stabilizer, resulting in inaccurate test results, and cannot effectively prove the oscillation suppression performance of the PSS of the power system stabilizer under test.

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