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

Method and system for neutral point potential balance of two-stage three-level three-phase four-wire energy storage converter

A three-phase four-wire system and potential balance technology, which is applied in the field of energy storage, can solve the problems of limited ability to suppress midpoint potential oscillation, increase switching loss, increase device voltage stress, etc., to achieve long-term stable operation and improve Effects of running stability and improving balance ability

Active Publication Date: 2022-07-19
CSR ZHUZHOU ELECTRIC LOCOMOTIVE RES INST
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Among them, the unbalanced component of the midpoint potential of the three-level inverter circuit includes a DC component and an AC component, which will cause many problems: 1) cause output voltage waveform distortion, and increase the content of low-order harmonics; 2) increase the voltage stress of the device, It is easy to cause overvoltage damage to the device
In the above method, the introduction of "transition vector" and the decomposition of zero level lead to an increase in the number of switches participating in the neutral point potential balance phase in a control cycle, which increases the switching loss, and for the case of a large load imbalance, the medium Limited ability to suppress point potential oscillations

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 system for neutral point potential balance of two-stage three-level three-phase four-wire energy storage converter
  • Method and system for neutral point potential balance of two-stage three-level three-phase four-wire energy storage converter
  • Method and system for neutral point potential balance of two-stage three-level three-phase four-wire energy storage converter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0052] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0053] like figure 1 As shown, the method for balancing the midpoint potential of a two-stage three-level three-phase four-wire energy storage converter in this embodiment includes the steps:

[0054] According to the reference value i of the low-voltage side inductor current in the three-level Buck / Boost circuit in the energy storage converter Lref , control the three-level Buck / Boost circuit to work in Boost mode or Buck mode;

[0055] Reference Δu based on midpoint potential ref The difference from the midpoint potential offset Δu is used to adjust the duty cycle of each switch in the Buck / Boost circuit in Boost mode or Buck mode, so that the total DC bus voltage is constant and the midpoint potential is balanced.

[0056] The invention aims at the two-stage three-level three-phase four-wire energy storage converter, and realizes the DC bus...

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 method and system for balancing the midpoint potential of a two-stage three-level three-phase four-wire energy storage converter, comprising: according to the low voltage in the three-level Buck / Boost circuit in the energy storage converter Side inductor current reference value i Lref , control the three-level Buck / Boost circuit to work in Boost mode or Buck mode; refer to Δu according to the midpoint potential ref The difference from the midpoint potential offset Δu is used to adjust the duty cycle of each switch in the Buck / Boost circuit in Boost mode or Buck mode, so that the total DC bus voltage is constant and the midpoint potential is balanced. The invention has the advantages of constant total voltage of the DC bus, balanced midpoint potential, and improved operation stability of the converter.

Description

technical field [0001] The invention mainly relates to the technical field of energy storage, in particular to a method and system for balancing the midpoint potential of a two-stage three-level three-phase four-wire energy storage converter. Background technique [0002] Energy storage technology has broad application prospects in the fields of improving power grid reliability, demand side management, and new energy access. The integration of energy storage into the power system can improve the security and stability of the power grid, alleviate the load peak-to-valley difference, improve power quality, and promote the application of renewable energy; it forms an independent microgrid with distributed power sources, which can improve the stability of the microgrid system. Electrochemical energy storage systems mainly include battery management systems (BMS) and bidirectional energy conversion systems (Power Conversion System, PCS). It mainly has the following functions: 1)...

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 Patents(China)
IPC IPC(8): H02J3/00H02J3/32H02J3/26H02J3/24H02M7/487H02M7/5387
CPCH02J3/00H02J3/32H02J3/26H02J3/24H02M7/487H02M7/53875Y02E40/50
Inventor 高首聪臧晓笛刘璐庞家猛汤腾蛟李琦薛冬良万能
Owner CSR ZHUZHOU ELECTRIC LOCOMOTIVE RES INST
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