Method for conducting multi-modal dynamic equivalence on complex electrical power systems except for generators

Abstract

The invention relates to a method for conducting multi-modal dynamic equivalence on complex electrical power systems except for generators. The method comprises the steps of S1 enabling an external system of a generator set to be studied to be equivalent to a parallel system of an infinite bus and N dynamic units, wherein the infinite bus is expressed as (a formula), and the N dynamic units are expressed as (a formula), S2 in a steady state condition, conducting load flow calculation or on-line measurement to obtain an initial steady-state value of a system, S3 exerting disturbance, recording obtained response quantity, S4 adopting spectral analysis or the prony method to analyze the number N of modals of significant variables at the end of the generator set to be studied, determining the total number N of dynamic equivalence units, S5 according to a multi-modal equivalent model, using data to select an appropriate identification method to identify parameters required to be equaled, and obtaining the dynamic equivalence result. The method better reflects dynamic characteristics of the external system of the generator set to be studied and improves accuracy of optimization design of an excitation controller.

Description

technical field [0001] The invention relates to a multi-modal dynamic equivalent method, in particular to a multi-modal dynamic equivalent method for complex power systems other than generators to be studied. This method can simplify the calculation model of the external power system on the basis of accurately simulating the influence of the external power system on the generator to be studied. Background technique [0002] The influence of the generator excitation system on the stability of the power system has been paid more and more attention, and the excitation controller is the core link for the function of the excitation system. Only by comprehensively considering the influence of the external complex power system on the research generator, can an excitation controller that meets the requirements of practical applications be designed. [0003] With the development of the power system, the scale of the power grid is getting larger and larger, and the system structure, ...

AI Technical Summary

Problems solved by technology

The actual engineering application proves that the error of using the infinite bus to simulate the remote large system of the generator to be studied is not large, but the infinite system cannot fully reflect the characteristics of the near-end system like the bus unit

Selecting a dynamic equivalent unit in parallel with the infinite bus can reflect the influence of the near-end system to a certain extent, but the rotor motion equation of the equivalent unit is second-order, only one frequency, and can only simulate one mode

When the power grid is disturbed, the terminal of the generator to be studied may contain multiple frequency components, and the dynamic equivalent of only one mode can not fully reflect the dynamic characteristics of the external system, so the accuracy of the optimal design of the excitation controller is limited

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