Capacitance current feedforward control method for grid-connected inverter with LCL filter

A filter capacitive current and feed-forward control technology, applied in the direction of converting AC power input to DC power output, electrical components, output power conversion devices, etc., can solve problems such as reduction, current difference system efficiency, and poor stability

Inactive Publication Date: 2011-05-25
HARBIN INST OF TECH
View PDF4 Cites 49 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0021] The purpose of the present invention is to solve the problem of poor stability of the current grid-connected inverter technology using LCL filter and the reduction of system efficiency due to the phase difference of grid-side voltage and current, and provides a grid-connected inverter with LCL filter. Capacitor current feed-forward control method for transformer

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
  • Capacitance current feedforward control method for grid-connected inverter with LCL filter
  • Capacitance current feedforward control method for grid-connected inverter with LCL filter
  • Capacitance current feedforward control method for grid-connected inverter with LCL filter

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0066] Specific implementation mode one: the following combination Figure 9 to Figure 17 Describe this embodiment, a capacitive current feed-forward control method of a grid-connected inverter with an LCL filter described in this embodiment:

[0067] Step 1. Collect the voltage of the three-phase grid, and transform the voltage of the three-phase grid into a voltage component in a two-phase stationary coordinate system by using a three-phase to two-phase coordinate transformation; and then obtain the grid voltage vector angle θ;

[0068] Step 2, collect the three-phase output current of the inverter, and transform the three-phase output current of the inverter into the current component in the two-phase stationary coordinate system by using the coordinate transformation from three phases to two phases; and then obtain the power grid according to step one The voltage vector angle θ transforms the two-phase current components into rotating coordinates and transforms them into t...

specific Embodiment approach 2

[0099] Specific implementation mode two: the following combination figure 1 This embodiment is described. This embodiment further describes the first embodiment. The topology of the grid-connected inverter with an LCL filter includes a DC source, a DC side filter capacitor C dc , three-phase full-bridge inverter circuit, LCL filter, DC side filter capacitor C dc Connected in parallel at both ends of the DC source, the two power output terminals of the DC source are respectively connected to the two input terminals of the three-phase full-bridge inverter circuit, and the three-phase output terminals of the three-phase full-bridge inverter circuit are connected to the three-phase output terminals of the LCL filter The phase input terminals are connected one by one, and the three-phase output terminals of the LCL filter are respectively connected to the three-phase power grid.

[0100] The three-phase full-bridge inverter circuit consists of a power switch tube S 1 ~S 6 consti...

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 capacitance current feedforward control method for a grid-connected inverter with an LCL filter and belongs to the field of electric energy conversion. The capacitance current feedforward control method for the grid-connected inverter with the LCL filter solves the problem of low stability of the grid-connected inverter with the LCL filter in the prior art and the problem of reduced efficiency of a system due to phase difference between grid side voltage and current. The method comprises the following steps of: 1, acquiring three-phase power grid voltage and acquiring a vector angle theta of the power grid voltage; 2, acquiring three-phase output current of the inverter and acquiring direct current components ild and ilq of the inverter side current; 3, acquiring three-phase filter capacitance current and acquiring direct current components icd and icq of the filter capacitance current; 4, setting set values of the inverter output current to perform proportional integral (PI) adjustment on a processed signal, outputting uq, performing PI adjustment on the processed signal, and output ud; and 5, inversely converting the ud and the uq into u(alpha) and u(beta) and performing pulse width modulation on the u(alpha) and the u(beta) to acquire six paths of switching signals which are used for controlling six switching tubes of the three-phase inverter so as to perform capacitance current feedforward control on the grid-connected inverter.

Description

technical field [0001] The invention relates to a capacitive current feed-forward control method of a grid-connected inverter with an LCL filter, belonging to the field of electric energy conversion. Background technique [0002] With the increasingly serious energy and environmental problems, new energy grid-connected power generation technologies such as wind power and photovoltaic power generation have attracted more and more attention, and have become an important part of the sustainable energy development strategy. As the core device connecting the power generation system with the grid, the grid-connected inverter directly affects the performance of the entire grid-connected power generation system, and has gradually become a research hotspot at home and abroad in recent years. [0003] Grid-connected inverters traditionally use L filters to suppress the high-order harmonics introduced by the on-off of power devices in the grid-connected current. However, with the incre...

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): H02M7/5387H02M1/12
CPCH02M1/126
Inventor 吴凤江王要强孙力赵克俞雁飞彭浩荣
Owner HARBIN INST OF TECH
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