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

Method and device for eliminating harmonic wave of photovoltaic grid connected charging system

A charging system and photovoltaic battery technology, applied to harmonic reduction devices, AC networks to reduce harmonics/ripples, etc., can solve problems such as high cost of APF, performance impact of three-phase AC power grid, and single function

Active Publication Date: 2013-07-03
NORTH CHINA ELECTRIC POWER UNIV (BAODING)
View PDF5 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

For the harmonics generated by electric vehicle charging, the use of APF can play a better role in suppressing, but the development of APF faces many obstacles such as high cost and single function.
[0005] Therefore, there is currently no suitable method for eliminating harmonics in the photovoltaic grid-connected charging system, so that the photovoltaic grid-connected charging system can compensate the harmonics generated by the electric vehicle while providing electric energy for the electric vehicle, avoiding the Harmonics generated during charging enter the three-phase AC grid and affect the performance of the three-phase AC grid

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 and device for eliminating harmonic wave of photovoltaic grid connected charging system
  • Method and device for eliminating harmonic wave of photovoltaic grid connected charging system
  • Method and device for eliminating harmonic wave of photovoltaic grid connected charging system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0036] The detailed process of calculating the first active command current, the second active command current and the third active command current corresponding to the three phases (A-phase, B-phase and C-phase), respectively, will be illustrated below (wherein the three-phase AC The grid is G, the photovoltaic cell is H):

[0037] Step a1: Obtain the phase voltage of the A phase of G, and obtain the voltage phase information θ according to the phase voltage;

[0038] Step b1: When it is determined that H is in the working state, obtain the voltage U of H H with current I H ;

[0039] Step c1: According to U H with I H Use MPPT method to obtain U corresponding to the maximum power value of H / H ;

[0040] Step d1: According to U H with U / H Calculate the error voltage ΔU H , and according to ΔU H Calculate the first active command current I corresponding to phase A A ;

[0041] Step e1: According to I A And use the corresponding relationship rule to calculate...

Embodiment 2

[0045] The detailed process of calculating the harmonic compensation command currents corresponding to the three phases (A-phase, B-phase, and C-phase) of the three-phase AC power grid is illustrated below (wherein the three-phase AC power grid is G, and the photovoltaic cell is h):

[0046] Step a2: Obtain the phase voltage of the A phase of G, and obtain the voltage phase information θ according to the phase voltage;

[0047] Step b2: Obtain the AC side charging current I corresponding to each of the three phases respectively A0 , I B0 with I C0 ;

[0048] Step c2: put I A0 , I B0 with I C0 Transform to get I α with I β ;

[0049] In this step, after obtaining I α with I β During the process, I can A0 , I B0 with I C0 Through the abc / αβ converter, the transformation from the three-phase stationary coordinate system to the two-phase stationary coordinate system is realized, and I get α with I β .

[0050] Step d2: put I again α with I β Transform to obtain ...

Embodiment 3

[0062] The detailed process of calculating the output command current obtained by combining the harmonic compensation command current corresponding to each phase and the active command current corresponding to each phase is illustrated below (wherein the three-phase AC grid is G, photovoltaic battery is H):

[0063] Step a3: the I obtained by step d1 and step e1 in the embodiment one A , I B with I C Transform to get the d-axis given current I d_pv , q-axis given current I q_pv , and let I q_pv =0;

[0064] In this embodiment, through the voltage regulator, after the proportional and integral operations of the voltage regulator, I A , I B with I C , get I d_pv with I q_pv .

[0065] Step b3: the I obtained in the step i2 in the embodiment two a_href , I b_href with I c_href Transform to get I d_href with I q_href ;

[0066] Step c3: put I d_pv with I d_href Combined to obtain the d-axis output command current I d_out ; put I q_pv with I q_href Combined to...

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 belongs to the technical field of an intelligent power grid and discloses a method and a device for eliminating harmonic wave of a photovoltaic grid connected charging system. The method particularly comprises the following steps: acquiring the phase voltage of any phase of a three-phase alternating current (AC) power grid; acquiring voltage phase information according to the phase voltage; acquiring the voltage and the current of a photovoltaic battery; acquiring active instruction current corresponding to three phases respectively according to phase locking voltage phase, the voltage of the photovoltaic battery and the current of the photovoltaic battery; acquiring AC side charging current corresponding to the three phases respectively; obtaining harmonic compensation instruction current of each phase according to the phase locking voltage phase and the AC side charging current; combining the harmonic compensation instruction current of each phase with the active instruction current to obtain output instruction current; and outputting the output instruction current to an electric automobile, so that the electric automobile can be charged, and influence on the performance of the three-phase AC power grid caused by the situation that the harmonic wave generated by charging the electric automobile enters the three-phase AC power grid is avoided.

Description

technical field [0001] The invention belongs to the technical field of smart grids, in particular to a method and device for eliminating harmonics in a photovoltaic grid-connected charging system. Background technique [0002] In recent years, the price of oil has been increasing day by day, and the world energy crisis has been deepening. How to rationally develop and utilize green energy has become an important issue. [0003] As a new generation of transportation, electric vehicles have incomparable advantages over traditional vehicles in terms of energy saving, emission reduction and reducing human dependence on traditional fossil energy. Electric vehicle V2G (Vehicle To Grid, two-way charging and discharging technology for electric vehicles) technology can not only make electric vehicles make full use of the power grid at the bottom of the grid, but also make it as a power source to provide power to the grid in the opposite direction during the peak period of power consu...

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): H02J3/01
CPCY02E40/40
Inventor 刘权陈征刘念肖湘宁
Owner NORTH CHINA ELECTRIC POWER UNIV (BAODING)
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com