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

Rapid robustness single-current feedback control method of LCL type grid-connected inverter

A technology of feedback control and inverter, which is applied in AC network circuits, AC network flicker reduction, photovoltaic power generation, etc. It can solve the problems of control delay, difficult selection, change of equivalent virtual damping resistance size and positive and negative directions, etc. , to achieve the effect of improving the dynamic performance

Active Publication Date: 2016-05-18
HUNAN UNIV
View PDF2 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to analyze the influence of control delay on the stability of the grid-connected inverter system and provide a fast and robust single-current feedback control method for LCL-type grid-connected inverters. , to solve the problem that the grid-connected inverter will have inherent control delay under digital control and will change the size and positive and negative directions of the equivalent virtual damping resistance, and completely eliminate the grid-connected current outer loop and the active damping inner loop. Lag calculation delay, and allow 0.5 times the switching cycle sampling and duty cycle calculation time, while solving the problem that the current LCL grid-connected inverter needs additional sensors or the introduction of single current feedback parameters is difficult to select

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
  • Rapid robustness single-current feedback control method of LCL type grid-connected inverter
  • Rapid robustness single-current feedback control method of LCL type grid-connected inverter
  • Rapid robustness single-current feedback control method of LCL type grid-connected inverter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0040] Such as figure 1 As shown, the single-phase photovoltaic LCL grid-connected inverter includes a boost circuit, an inverter circuit, an LCL filter circuit, an A / D sampling circuit, a controller DSP2812, and a drive protection circuit. The photovoltaic array, boost chopper circuit , inverter circuit, LCL filter circuit, and power grid are connected in sequence; the output voltage of the photovoltaic array is U pv , the photovoltaic array output current is I pv ; The input end of the A / D sampling circuit is connected with the LCL filter circuit; the boost circuit is composed of a capacitor C pv , inductance L 0 , Diode VD 0 , Insulated Gate Bipolar Transistor (IGBT) Q 0 composition, which flows through the inductor L 0 The current is I L0 ; The inverter circuit consists of inverter DC side capacitor C dc and Insulated Gate Bipolar Transistors (IGBT)S 1 , S 2 , S 3 and S 4 composition; the controller DSP2812 is connected with the input end of the drive protection...

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 discloses a rapid robustness single-current feedback control method of an LCL type grid-connected inverter. Single-current feedback control is introduced, a rapid robustness PWM modulation method is combined, and grid-connected control of the inverter is realized. According to the method, the grid-connected current is sampled, extra sensors are not needed, the hardware cost is reduced, and the system reliability is improved. According to the rapid robustness PWM control method, the duty cycle limitation is not introduced, the calculation time delay of one-step delay of a grid-connected current outer loop and an active damping inner loop is completely eliminated, the essential requirement that the positive and negative dividing frequency of an equivalent damping resistor is higher than the design range of the LCL resonant frequency is realized, the method allows half of the switching period of sampling and duty cycle calculating time, and the overall robustness and the dynamic performance of the grid-connected inverter are enhanced.

Description

technical field [0001] The invention relates to the field of PWM inverter control and new energy sources thereof, in particular to a fast and robust single current feedback control method for an LCL type grid-connected inverter. Background technique [0002] Grid-connected inverters, as the core device connecting distributed energy sources and public grids, play a vital role in distributed power generation systems. Its output filter adopts LCL type filter, which can effectively suppress the high-frequency harmonics output by the inverter, reduce the volume and quality of the filter, and has important application value in engineering. However, the LCL filter is a low-damping third-order system, which has resonance problems, which can easily lead to instability of the grid-connected inverter. Now there are a lot of literature to discuss and solve the resonance problem of the LCL-type grid-connected inverter, mainly including the capacitor branch The passive damping method of ...

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): H02J3/38
CPCH02J3/002H02J3/383H02J2203/20H03K7/08Y02E10/56
Inventor 陈燕东王自力周乐明杨苓周小平伍文华怀坤山罗安
Owner HUNAN 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

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