Neutral-point potential balance control device and method for three-level inverter

A three-level inverter and potential balancing technology, which is applied in the direction of output power conversion device, electrical components, AC power input conversion to DC power output, etc., can solve the problem of adding a large number of components, unbalanced midpoint voltage, and cost increase and other problems, to achieve the effect of simple structure and control, suppression of midpoint potential shift, and improvement of stability

Inactive Publication Date: 2012-12-26
江苏中航动力控制有限公司
View PDF4 Cites 29 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] There is an inherent disadvantage of the three-level inverter, that is, there is a problem of unbalanced midpoint voltage
Suppressing the midpoint potential shift from the software alo

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
  • Neutral-point potential balance control device and method for three-level inverter
  • Neutral-point potential balance control device and method for three-level inverter
  • Neutral-point potential balance control device and method for three-level inverter

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0035] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation examples.

[0036] figure 1 It is a block diagram of the system structure of the three-level inverter mid-point balance control device described in this embodiment, as shown in figure 1 As shown, the three-level inverter midpoint balance control device of the present invention includes: a voltage acquisition unit 101, a proportional-integral control unit 102, a pulse width control unit 103, and a voltage regulation unit 104, wherein the above-mentioned units are connected accordingly .

[0037] The voltage acquisition unit 101 is used to acquire the capacitor voltage on the bus and the capacitor voltage under the bus, and the input terminal of the voltage acquisition unit is connected to the bus bar and the midpoint terminal of the bus bar of the three-level inverter;

[0038] A proportional-integral control unit 102, configured to perform pr...

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 is suitable for the field of power electronics, and relates to a neutral-point potential balance control device and method for a three-level inverter. The device comprises a voltage acquisition unit, a proportional-integral control unit, a pulse width control unit and a voltage regulating unit. According to the neutral-point potential balance control device provided by the invention, a control quantity is generated by detecting capacitor voltages above and below a bus in real time and performing proportional-integral control processing, and the pulse width modulation duty ratio of a voltage regulating unit power tube is regulated according to the control quantity. The neutral-point potential balance control device is simple in structure, and is easy and convenient for control realization; and a control effect is irrelevant to the modulation ratio and power factor of an inversion system, and neutral-point potential can be controlled in a relatively small range.

Description

technical field [0001] The invention belongs to the field of power electronics, and relates to a control device and method for midpoint potential balance of a three-level inverter. Background technique [0002] The three-level inverter has the advantages of compact structure, low harmonic content of output voltage and current, and the voltage borne by the switching tube is only half of the DC bus voltage. Therefore, it is widely used in medium and high voltage and high power occasions. [0003] There is an inherent disadvantage of the three-level inverter, that is, there is a problem of unbalanced midpoint voltage. The unbalanced midpoint voltage will cause serious harm: the output voltage waveform of the inverter is distorted; the voltage borne by the switching device is unbalanced; the voltage fluctuation of the DC side capacitor reduces the life of the capacitor. In order for the inverter to work normally, efforts should be made to keep the midpoint voltage balanced. ...

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): H02M7/483
Inventor 王律明张志红陈东
Owner 江苏中航动力控制有限公司
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