Reduction of DC-link capacitor in case of cascade multilevel converters by means of reactive power control

Author

Gohil, Ghanshyamsinh ; Huai Wang ; Liserre, Marco ; Kerekes, Tamas ; Teodorescu, Remus ; Blaabjerg, Frede

Author_Institution

Dept. of Energy Technol., Aalborg Univ., Aalborg, Denmark

fYear

2014

fDate

16-20 March 2014

Firstpage

231

Lastpage

238

Abstract

A new method to selectively control the amount of dc-link voltage ripple by processing the desired reactive power by a DC/DC converter in an isolated AC/DC or AC/DC/AC system is proposed. The concept can reduce the dc-link capacitors used for balancing the input and output power and thereby limiting the voltage ripple. It allows the use of a smaller dc-link capacitor and hence a longer lifetime and at the same time high power density and low cost can be achieved. The isolated DC/DC converter is controlled to process the desired reactive power in addition to the active power. The control system to achieve this selective degree of compensation is proposed and verified by Simulations.

Keywords

AC-DC power convertors; DC-AC power convertors; DC-DC power convertors; capacitors; reactive power control; AC-DC system; AC-DC-AC system; DC-DC converter; DC-link capacitor reduction; active power; cascade multilevel converters; dc-link voltage ripple; high power density; reactive power control; voltage ripple; Bridge circuits; Capacitors; Inductors; Reactive power; Switches; Voltage control; Zero voltage switching;

fLanguage

English

Publisher

ieee

Conference_Titel

Applied Power Electronics Conference and Exposition (APEC), 2014 Twenty-Ninth Annual IEEE

Conference_Location

Fort Worth, TX

Type

conf

DOI

10.1109/APEC.2014.6803315

Filename

6803315