A Modeling Method for Harmonic Transmission of Electromagnetic Current Transformer

Abstract

The invention relates to a harmonic transmission modeling method of an electromagnetic current transformer. The harmonic transmission modeling method comprises the following steps: obtaining a primary-side harmonic current signal of the current transformer, detecting a primary-side harmonic current effective value and circuit transformer remanence, ensuring that a hysteresis loop model based on improved J-A is the hysteresis loop model associated with primary current frequency change information, obtaining secondary current corresponding to each component signal of a secondary side of the current transformer after hysteresis loop model transmission is carried out, obtaining an effective value generated after the secondary current is transmitted, and calculating the ratios of transformation of the current transformer under different frequencies. The harmonic transmission modeling method which is put forward by the invention can realize conversion simulation from primary current to secondary current under different frequencies, and improves metering and measurement accuracy under a harmonic condition.

Description

technical field [0001] The invention relates to the fields of power electronics and power quality measurement, in particular to a modeling method for harmonic transmission of electromagnetic current transformers. Background technique [0002] Electromagnetic current transformer is an important electrical equipment in the power system, which transmits and transforms primary current signals for metering, measurement, and protection equipment. Since the electromagnetic current transformer is affected by the hysteresis loop, the electromagnetic current transformer will enter the saturation section of the hysteresis loop and cause secondary current distortion. With the large number of applications of power electronic equipment such as air conditioners, UPS, and electric arc furnaces, there are harmonic sources of different frequencies in the distribution network of 35kV and below, which seriously affect the power quality of public connection points. The traditional current trans...

AI Technical Summary

Problems solved by technology

However, the improved model and the classic J-A model cannot be accurately used for the simulation of current transformers under the condition of harmonics

[0011] Using artificial intelligence algorithms such as neural network and genetic algorithm to simulate the current mutual inductance model, the modeling is complicated, requires a lot of sample data, the physical concept is not clear, and the number of iterations is too large to calculate.

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