Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Harmonic wave measuring and correcting method for capacitor voltage transformer through transformation ratio fitting

A voltage transformer, measurement and correction technology, applied in the direction of measuring devices, measuring electrical variables, instruments, etc., can solve the problems of not involving quantitative analysis and calculation methods, not providing capacitive voltage transformer correction methods, and lack of measurement error analysis, etc.

Active Publication Date: 2016-03-09
WUHAN UNIV
View PDF6 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the existing research mainly focuses on the qualitative analysis of the capacitor voltage transformer (CVT), and does not involve the quantitative analysis and calculation method of the source of each error peak point, nor does it give the error characteristics of the capacitor voltage transformer (CVT) correction method
[0004] The current research on the mechanism of CVT measurement error under harmonic conditions is not in-depth, and there are still insufficient quantitative analysis of different factors affecting CVT harmonic measurement error, especially the lack of analysis of CVT harmonic measurement error with different dampers
Correction for CVT harmonic measurement errors is also missing

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Harmonic wave measuring and correcting method for capacitor voltage transformer through transformation ratio fitting
  • Harmonic wave measuring and correcting method for capacitor voltage transformer through transformation ratio fitting
  • Harmonic wave measuring and correcting method for capacitor voltage transformer through transformation ratio fitting

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0040] The technical solution of the present invention will be specifically described below in conjunction with the accompanying drawings and embodiments.

[0041] The present invention applies equal voltage values ​​of different frequencies to the primary side of the capacitive voltage transformer adopting the fast saturation type damper, and the ratio of the measurement result of the secondary side to the voltage applied on the primary side is the actual transformation ratio of the capacitive voltage transformer. The fitting function of the variable ratio frequency response characteristic curve is obtained by polynomial fitting and fractional fitting. According to the equivalent circuit parameters of the capacitive voltage transformer, the frequency of each resonance point is obtained, and the actual transformation ratio value at the resonance frequency is obtained by using the voltage division formula. According to the resonant frequency and the actual transformation ratio,...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention brings forward a harmonic wave measuring and correcting method for capacitor voltage transformers through transformation ratio fitting. The method includes the steps: establishing a consistent equivalent circuit for capacitor voltage transformers with the same voltage level, conducting fitting according to equivalent circuit component parameters of a preset model, obtaining a transformation ratio amplitude-frequency response curve and a phase frequency response characteristic curve, adjusting the curves through a translation method or the like on the basis of a fitting result for different equivalent circuit component parameters of other models, and finally realizing correction. The wideband characteristics of capacitor voltage transformers are taken as standards for the actual transformation ratio of the capacitor voltage transformers, a measurement result of the capacitor voltage transformers is corrected at the harmonic frequency, and the problem that capacitor voltage transformers cannot be applied to harmonic wave measurement is solved. The harmonic wave measuring and correcting method is simple in calculation, exhibits the real-time performance, and enables the application bandwidth of capacitor voltage transformers to be increased.

Description

technical field [0001] The invention relates to the field of voltage measurement of capacitive voltage transformers, in particular to a method for measuring and correcting harmonics of capacitive voltage transformers using transformation ratio fitting. Background technique [0002] Capacitive voltage transformer (CVT) is widely used in the voltage measurement of the neutral point directly grounded high-voltage system, and it is the most important secondary signal source for the harmonic measurement of the high-voltage level system at present. However, in the national standard GB / T "Power Quality Harmonics of Public Power Grids", it is clearly stipulated that "capacitive voltage transformers cannot be used for harmonic measurement". [0003] Most of the current related research focuses on the principle analysis of the harmonic measurement error of capacitor voltage transformer (CVT). By establishing the harmonic equivalent circuit and giving the calculation method of its cor...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01R35/02
CPCG01R35/02
Inventor 乐健柳永妍周武刘开培
Owner WUHAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products