Method for using one-phase photovoltaic grid-connected inverter to detect network voltage phase

A grid voltage and inverter technology, applied to the phase angle between voltage and current, instruments, measuring devices, etc., can solve the problems of poor phase-locking accuracy, inability to filter out harmonic interference, and poor phase-locking accuracy , to achieve the effect of strong anti-interference ability, good adaptability and quick response

Active Publication Date: 2013-12-25
宁夏隆基宁光仪表股份有限公司
View PDF5 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Among them, the delay method only needs to construct an array, which has a simple structure, but because it cannot filter out the harmonic interference in the collected grid voltage signal, the phase-locking accura

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
  • Method for using one-phase photovoltaic grid-connected inverter to detect network voltage phase
  • Method for using one-phase photovoltaic grid-connected inverter to detect network voltage phase
  • Method for using one-phase photovoltaic grid-connected inverter to detect network voltage phase

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0027] The specific method of its realization mainly has five steps: the first step is to filter the signal through the band-pass filter module. This filter has a great attenuation of the signal outside the resonant frequency. Use this feature to achieve the collected voltage signal Filter out harmonics and DC components. In the second step, the filtered signal Vα is passed through the quadrature signal generating module to generate a voltage signal Vβ lagging 90 degrees. The third step is to use the last estimated angle θ'to perform d-q transformation on Vα and Vβ, and perform the difference operation between the result Vq and 0. The fourth step is to do a proportional integral (PI) operation on the difference. In the fifth step, the calculation result in the fourth step and the base angular frequency of the power grid will be summed to obtain the estimated angular frequency of the power grid. The sixth step is to integrate the estimated angular frequency to obtain the estim...

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 relates to a method for using a one-phase photovoltaic grid-connected inverter to detect a network voltage phase. The method for using the one-phase photovoltaic grid-connected inverter to detect the network voltage phase is characterized by comprising the following steps of (1) carrying out filtering processing on collected network voltage signals, removing higher harmonic except direct-current components and fundamental frequencies through filtration, and obtaining a signal Valpha; (2) carrying out 90-degree phase shifting on the obtained signal Valpha, and generating a signal Vbeta, namely, generating a set of orthogonal signals; (3) carrying out d-q conversion on the obtained orthogonal signal Valpha and the obtained orthogonal signal Vbeta according to an estimation angle theta' of a power grid, and obtaining a Vd and a Vq, wherein the initial value of the estimation angle theta' of the power grid is set to be zero, the operation value can be updated through the step (4) and the step (5), and thus the estimation angle theta' can reach the real network voltage phase after the transient state process ends. The method for using the one-phase photovoltaic grid-connected inverter to detect the network voltage phase has the advantages that interference of the harmonic in the collected network voltage signals can be removed through filtration, signals, with the direct-current components, in the collected network voltage signals can be removed through filtration, and higher phase locking accuracy can be achieved.

Description

technical field [0001] The invention relates to a method for detecting grid voltage phases by using a single-phase photovoltaic grid-connected inverter. Background technique [0002] At present, most single-phase (photovoltaic) grid-connected inverters use zero-crossing detection to track the grid voltage phase, which has poor anti-interference performance. In addition, there is also a single-phase phase-locked technology based on a synchronous coordinate system based on a three-phase phase-locked loop. This type of method needs to construct a pair of orthogonal signals. Currently, the methods commonly used to construct orthogonal signals include the delay method using array storage and A phase shift of 90° is realized based on a generalized second-order integrator. Among them, the delay method only needs to construct an array, which has a simple structure, but because it cannot filter out the harmonic interference in the collected grid voltage signal, the phase-locking acc...

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
IPC IPC(8): G01R25/04
Inventor 赵四海李建炜裴云庆武晓勇金新张万菊屈子旭李波
Owner 宁夏隆基宁光仪表股份有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap