Capacitor Balance Issues of the Diode-Clamped Multilevel Inverter Operated in a Quasi
#1


[attachment=6628]


ABSTRACT

A new operational mode for diode-clamped multilevel inverters termed quasi two-level operation is proposed. Such operation aims to avoid the imbalance problem of the dc-link capacitors for multilevel inverters with more than three levels and reduces the dc-link capacitance without introducing any significant voltage ripple at the dc-link nodes. The proposed operation can be generalized for any number of levels. The validity of the proposed multilevel inverter operational mode is confirmed by simulations in mat lab v7.5. .
The multilevel concept is based on a step approximation to a sinusoidal voltage. Multilevel inverters belong to the inverter circuit family, where the output voltage comprised more than two intermediate discrete voltage levels. The purpose of these circuits is to generate a high-voltage waveform using lower voltage rating switching devices connected in series. Typically, the series-connected devices are sequentially switched, producing an output pattern that contains discrete predefined steps. Each switch blocks its rated normal voltage, but the total output voltage can be much higher. Multilevel inverters, in general, have advantages over conventional two level inverters due to their ability to handle high voltage with minimum voltage stress on the switching devices, have a low harmonic content in the output voltage, generate lower dv/dt, and have a lower common-mode voltage, which results in reduced stress on motor bearings in drive applications. In diode-clamped multilevel inverters, device voltage sharing is achieved via the clamping diodes, whereas lower dv/dt is achieved with stepped voltage changes. However, the diode clamped multilevel suffers from dc-link capacitor unbalance to balance the dc-link series capacitors, two main balancing approaches have been proposed: 1) the use of auxiliary balancing networks and 2) the manipulation of redundant switch states.


OVERVIEW OF THE PROJECT
SERIES connection of semiconductor devices is a solution for achieving higher converter voltage ratings; however, devices suffer from unbalanced static and dynamic voltage sharing, and the output voltage has a high dv/dt. A multilevel inverter can overcome these disadvantages. The multilevel concept is based on a step approximation to a sinusoidal voltage. Multilevel inverters belong to the inverter circuit family, where the output voltage comprised more than two intermediate discrete voltage levels. The purpose of these circuits is to generate a high-voltage waveform using lower voltage rating switching devices connected in series. Typically, the series-connected devices are sequentially switched, producing an output pattern that contains discrete predefined steps. Each switch blocks its rated normal voltage, but the total output voltage can be much higher. Multilevel inverters, in general, have advantages over conventional two level inverters due to their ability to handle high voltage with minimum voltage stress on the switching devices, have a low harmonic content in the output voltage, generate lower dv/dt, and have a lower common-mode voltage, which results in reduced stress on motor bearings in drive applications. In diode-clamped multilevel inverters, device voltage sharing is achieved via the clamping diodes; where as lower dv/dt is achieved with stepped voltage changes. However, the diode clamped multilevel suffers from dc-link capacitor unbalance to balance the dc-link series capacitors, two main balancing approaches have been proposed: 1) the use of auxiliary balancing networks and 2) the manipulation of redundant switch states. Auxiliary networks achieve capacitor balance by the transfer of energy between the capacitors or the direct transfer of energy from the page link supply.
Reply
#2

thanks man for the great work and i want the simulation Photovltaic inverter single phase for residentiel
Reply

Important Note..!

If you are not satisfied with above reply ,..Please

ASK HERE

So that we will collect data for you and will made reply to the request....OR try below "QUICK REPLY" box to add a reply to this page
Popular Searches: capacitor animation powerpoint, diode matlab code, capacitor types, transistor as diode, quasi judicial immunity, impatt diode in hindi, seminar on multilevel inverter,

[-]
Quick Reply
Message
Type your reply to this message here.

Image Verification
Please enter the text contained within the image into the text box below it. This process is used to prevent automated spam bots.
Image Verification
(case insensitive)

Possibly Related Threads...
Thread Author Replies Views Last Post
  Implementation Issues in Spectrum Sensing for Cognitive Radios seminar surveyer 3 3,639 16-03-2015, 02:23 PM
Last Post: seminar report asees
  Single-phase half-bridge inverter project report helper 2 2,839 21-12-2012, 11:34 AM
Last Post: seminar details
  Electronic starter for single phase induction motors with starting capacitor computer girl 1 1,633 13-11-2012, 11:59 AM
Last Post: seminar details
  Junction Diode seminar class 1 1,841 08-11-2012, 12:56 PM
Last Post: seminar details
  Flexible Organic Light Emitting Diode full report project topics 1 3,310 15-03-2012, 10:06 AM
Last Post: seminar paper
  Issues of Routing IN VANET project topics 1 2,193 20-02-2012, 10:25 AM
Last Post: supriyavpatil
  Simulation of six-step inverter induction motor drive seminar class 1 2,464 08-02-2012, 10:09 AM
Last Post: seminar addict
Shocked Organic light emitting diode OLED seminars report electronics seminars 24 25,457 01-08-2011, 10:37 AM
Last Post: seminar addict
  ISSUES ON SOLAR GENERATOR-INTERFACING WITH CURRENT-FED MPP-TRACKING CONVERTERS smart paper boy 0 1,150 15-07-2011, 10:34 AM
Last Post: smart paper boy
  ISSUES IN AD-HOC NETWORKS full report project topics 0 1,335 14-04-2011, 03:59 PM
Last Post: project topics

Forum Jump: