Harmonic Liability Assessment Method Applicable to Industrial and Mining Enterprises

Abstract

The invention discloses a harmonic responsibility evaluation method suitable for an industrial and mining enterprise. The method comprises the following steps of 1, collecting three-phase voltage andthree-phase current at a PCC of a power distribution network of the industrial and mining enterprise and three-phase current at head ends of user feeders; 2, carrying out orthogonal coordinate transformation; 3, carrying out fast Fourier decomposition; 4, computing a similarity current at the PCC of the power distribution network of the industrial and mining enterprise; 5, computing an equivalentharmonic current generated by a harmonic voltage of a public power distribution network; 6, evaluating harmonic responsibility of a system side of the power distribution network of the industrial andmining enterprise; 7, computing a similarity current at the head end of the Mth user feeder; 8, computing a non-similar current at the head end of the Mth user feeder; 9, computing active power of thehth harmonic at the head end of the Mth user feeder; 10, computing a harmonic current generated by a harmonic source user; and 11, evaluating the harmonic responsibility of the user. According to themethod disclosed by the invention, accurate positioning and harmonic responsibility evaluation of the harmonic sources at the system side of the power grid and various users of the industrial and mining enterprise are realized from the perspective of current decomposition.

Description

technical field [0001] The invention belongs to the technical field of harmonic liability assessment, and in particular relates to a harmonic liability assessment method suitable for industrial and mining enterprises. Background technique [0002] High-power frequency conversion speed control devices and impact loads have made the harmonic pollution and imbalance of power grids in industrial and mining enterprises increasingly prominent. Excessive harmonic content has caused additional losses in electrical equipment, misoperation of relay protection devices, and "group damage" caused by high-voltage fuses. Explosion" phenomenon, and even lead to safety problems such as high-frequency resonance overvoltage. Due to the complex sources of harmonics in power grids of industrial and mining enterprises, after a resonant overvoltage accident occurs, only by accurately finding the source of harmonics and clarifying the party responsible for the accident can the accident reoccur effe...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a harmonic liability assessment method suitable for industrial and mining enterprises in view of the deficiencies in the above-mentioned prior art. From the perspective of current decomposition, similar current components and non-similar current components are calculated according to voltage waveforms , realize the accurate positioning of the harmonic sources of the power grid system side of industrial and mining enterprises and each user inside the industrial and mining enterprises, solve the problems of difficult acquisition of harmonic impedance parameters of the system and users, and inaccurate harmonic responsibility assessment, and facilitate popularization and use

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